Method and apparatus for cleaning treatment

Information

  • Patent Grant
  • 6770149
  • Patent Number
    6,770,149
  • Date Filed
    Tuesday, April 23, 2002
    22 years ago
  • Date Issued
    Tuesday, August 3, 2004
    20 years ago
Abstract
A method for a cleaning treatment including a step of forming, in a coating mechanism, a coating film on a substrate provided within a cup. The method further includes dissolving, in an edge cleaning mechanism, a portion of the coating film on the substrate using a cleaning liquid, and recovering at least a portion of used cleaning liquid from the edge cleaning mechanism. The recovered cleaning liquid is stored and a level of the stored cleaning liquid is detected. The method also includes supplementing a fresh cleaning liquid to the stored cleaning liquid when a detected level of the stored cleaning liquid is lower than a predetermined level, and using a mixture of the supplemented fresh cleaning liquid and the stored cleaning liquid to clean the cup of the coating mechanism.
Description




BACKGROUND OF THE INVENTION




The present invention relates to a method and apparatus for a cleaning treatment in a system, in which, for example, substrates used for a liquid crystal display (hereafter referred to as LCD) and a semiconductor device are treated.




Recently, it has become an urgent need in apparatuses for various kinds treatment, for example in a resist coater which is used to form a resist film on a LCD substrate, that the size of an apparatus itself is reduced, the production cost is decreased and in addition a running cost of the apparatus is decreased.




In a resist coater generally used in a fabrication process of LCD, treatments of resist coating and cleaning are given on a glass substrate (an object to be treated), and there are two kinds of resist coater, which are of types of spin-coating and spray-coating.




A resist coater of a spin-coating type comprises, for example: a spin chuck, on which a glass substrate is mounted, and which is free to be shiftable vertically while being free to be rotatable; a resist solution instillator which supplies a resist liquid in the middle potion of the substrate drop by drop; a jet nozzle of a cleaning liquid to clean the surface of the substrate; and a rotary cup and a drainage cup being disposed outside the substrate in a manner doubly surrounding the substrate, wherein the rotary cup is inside the stationary cup and the rotary cup receives the resist liquid or a thinner flowing out or flying out from the substrate.




In such a resist coater, a glass substrate is mounted on a spin chuck which is free to be shiftable vertically while being free to be rotatable and a resist liquid is supplied to the middle portion of the substrate drop by drop while rotating the substrate to form a uniform resist film by a centrifugal force. In the case, a residue of the resist liquid which flows out or flies out from the substrate is received by the rotary cup to be discharged. In a following step, a height of the spin chuck is changed and a cleaning liquid is supplied from the cleaning liquid jet nozzle to the edge of the substrate to clean the edge portion of both surfaces of the substrate and a waste liquid is received by the drainage cup to be discharged. As a cleaning liquid, a solvent such as a thinner is used, since it is less in pollution and higher in safety.




In the same resist coater, since a used cleaning liquid (a waste liquid) has a lot of a resist ingredient dissolved therein, the used cleaning liquid cannot be reused on the substrate and is stored in a waste liquid storage unit through a waste liquid pipe. The waste liquid stored in the storage unit is wasted when it is accumulated to some extent.




In the drainage cup, since a thinner constantly including a resist ingredient is fed, the resist ingredient is piled up as a deposit on the inner wall of the cup in a adhered manner. When the resist ingredient is adhered and piled up to some extent, clogging will be caused, the inner wall of the drainage cup has been conventionally cleaned at an interval and the deposit has been separated off. Such a situation is also applied to the case of the rotary cup which directly receive the used resist liquid itself.




However, in a conventional resist coater, a thinner is sprayed toward the inner surface of a cup from a nozzle exclusively used for cleaning the inside of the cup disposed in the cup in order to remove the deposit inside the cup and therefore a lot of the thinner is required.




As described above, there has been a problem in a conventional resist coater, which is an apparatus for a coating treatment, that contamination such as an resist is adhered on the inner wall of a cup when the treatment is repeated and such contamination requires a lot of the thinner to be removed, so that the expense for cleaning is accumulated.




Besides, a used cleaning liquid cannot be used in a cleaning treatment of a glass substrate to be cleaned and therefore the used cleaning liquid is wasted as a waste liquid, which has been another cause to increase a running cost.




While application of a resist liquid on the surface of an object to be treated such as a LCD substrate has been effected by a spin coating method, In the case, since a LCD substrate has a rectangular shape, which causes a turbulent flow in the air by rotation, there arises a problem that uniformity of a thickness of a resist film cannot be maintained.




For such a reason, conventionally a surrounding space above, under and near the sides of a spin chuck as a holding means for holding LCD substrate and a LCD substrate are enclosed by a rotary cup with a cover and a rectifying plate is disposed above the LCD substrate in the rotary cup with a cover and the air supplied through an air supply port formed in the cover of the rotary cup with a cover is rectified by the rectifying plate to be discharged through an exhaust port located at the bottom of the rotary cup. In such a manner, A disorder in thickness of a resist film by a turbulence in the air have been avoided. A stationary cup is so disposed as to enclose the side and lower portions of the covered cup in order to prevent an air stream created by rotation of the rotary cup from flowing back into the inside of the rotary cup.




However, in a resist coater in which a resist liquid is applied by a spin coating method of this kind, a resist solution is sprayed outwardly by an centrifugal force and therefore a resist is adhered on the inner side and the bottom of the rotary cup, back surface of the covered cup, and the lower surface of the rectifying plate and the like. Besides, there is a fear that the resist is adhered in the inner side and the bottom of the stationary cup. In such a manner, a resist adhered on the rotary cup, the inside of the stationary cup, on the cover, the rectifying plate and the like is dried to produce particles. If the particles are adhered on a LCD substrate, a difficulty occurs on a circuit patterning and the like and at the same time a problem of reduction in a yield is resulted.




BRIEF SUMMARY OF THE INVENTION




It is an object of the present invention to provide a method and apparatus for a cleaning treatment, in which a cleaning liquid to be used for cleaning a treated object is effectively used.




It is a second object of the present invention to provide an apparatus for a treatment in which a cleaning solution is reused.




It is a third object of the present invention to provide an apparatus for a treatment in which a cleaning efficiency of a vessel can be achieved.




It is a fourth object of the present invention to provide an apparatus for a treatment in which a running cost of the whole apparatus can be reduced.




The fourth object of the present invention is to provide a method and apparatus for a cleaning treatment in which a coating liquid, such as a resist, adhered on a rotary cup and a stationary cup of a coating mechanism is removed to improve a yield.




In order to achieve the above mentioned objects, a method for a cleaning treatment of the present invention has a feature that the method comprises the steps of: cleaning a treated object is cleaned with a cleaning liquid supplied; then recovering the cleaning liquid; removing gas in the recovered cleaning liquid by separation; then storing the recovered liquid in a storing section; and reusing the stored cleaning liquid for cleaning an object to be treated.




In the method for a cleaning treatment, it is preferred that the stored cleaning liquid is used for cleaning the apparatus for a treatment for the object. Besides, it is also possible in a method for a cleaning treatment of the present invention that a cleaning liquid is additionally supplied to replenish the storing section for the recovered cleaning liquid with a cleaning liquid and a mixture of the added cleaning liquid and the recovered cleaning liquid is used for cleaning.




An apparatus for a cleaning treatment of the present invention comprises: first supply means for supplying a cleaning liquid to an object treated; a recovering pipe for recovering a cleaning liquid already used for cleaning of the object treated; gas/liquid separation means for separating gas from the recovered liquid by separation; a cleaning liquid storing section for storing the cleaning liquid separated by the gas/liquid separation means; and second cleaning liquid supply means for supplying the cleaning liquid in the cleaning storing section to an object o be cleaned.




In the apparatus for a cleaning treatment, it is preferred that the apparatus for a cleaning treatment further comprises second cleaning liquid supply means. In the same apparatus for a cleaning treatment of the present invention, the first cleaning liquid supply means has a plurality of nozzle holes for jetting a cleaning liquid toward positions, which do not interfere with each other, on both surfaces of peripheral portion of the treated object, and the recovering pipe is provided at a position outwardly and laterally of the nozzles. In the case, an opening of a route for a waste liquid which are connected to the recovering pipe at the other end preferably has a taper having the maximum diameter at the outermost end in order to effectively receive the cleaning liquid jetted from the nozzle holes. That is, it is preferred that the nozzle holes are located in the inside of the opening at the outermost end of the waste liquid route wherein the end portion has a taper and the diameter of the opening is the maximum in the tapered end portion. Moreover, the above mentioned cleaning liquid storing section can be preferably formed in such a manner that a cleaning liquid is directly supplemented from a cleaning liquid supply source.




According to the present invention, a cleaning liquid is supplied to an object to clean it, thereafter, the cleaning liquid is recovered, gas is separated and removed from the recovered liquid, then the recovered liquid is stored, the stored cleaning liquid is reused for cleaning of an object to be cleaned and thus the cleaning liquid can be effectively used. Accordingly, since a usage amount of the cleaning can be reduced, the cost is reduced and natural resources can be effectively used.




An efficiency of usage of a cleaning liquid in the same treatment system can be further increased by reusing a stored cleaning liquid for cleaning of an apparatus for a cleaning treatment, whereby a scale of the apparatus can be smaller, since the piping system of the cleaning liquid is simpler.




A cleaning efficiency is further increased by supplementing the storing section of the recovered cleaning liquid with the fresh cleaning liquid and using a liquid mixture of the supplementing cleaning liquid and recovered cleaning liquid for cleaning the object to be cleaned and a reliability of the apparatus for a cleaning apparatus can be improved. With the first cleaning supply means having nozzle holes to jet the cleaning liquid toward positions on both surface of a peripheral portion of the object treated at which streams of the cleaning liquid do not interfere with each other and with the recovering pipe provided at a position outwardly and laterally of the nozzle holes, since a cleaning liquid which is used in a first cleaning step and which is supplied from the first cleaning liquid supply means is recovered with a good efficiency, loss of the cleaning liquid is avoided and as a result a cleaning efficiency can be increased.




A second apparatus for a treatment of the present invention is directed to an apparatus comprising: a vessel for recovering a treatment liquid flowing out or flying out when an object is treated; cleaning means for cleaning the inner wall surface of the vessel by supplying a cleaning liquid into the vessel; and a circulating system for recovering a discharged liquid discharged from the vessel when the inner wall surface of the vessel is cleaned by the cleaning means and supplying it to the cleaning means.




In the second apparatus of the present invention, since the discharged liquid from the vessel when the inner wall surface of the vessel is cleaned by means of the cleaning means is recovered by the circulating system and supplied to the cleaning means which is used for cleaning the inside of the vessel, the cleaning liquid can be reused. Thereby, a usage volume of the cleaning liquid is reduced and at the same time the running cost of the whole apparatus can be reduced.




A third apparatus for a treatment of the present invention is directed to an apparatus defined as the second apparatus, wherein the circulating system comprises: a fresh cleaning liquid storing section for an unused cleaning liquid; a discharged liquid storing section for storing a discharged liquid discharged from the vessel; a cleaning liquid supply means for supplying the discharged liquid stored in the discharged liquid storing section and the unused cleaning liquid stored in the fresh cleaning liquid storing section, singly or in mixture, to the cleaning means.




In the third apparatus, since the discharged liquid stored in the discharged liquid storing section and the unused cleaning liquid stored in the fresh cleaning liquid storing section, singly or in mixture, are supplied to the cleaning means, no difficulty arises in cleaning a cup.




A fourth apparatus for a cleaning treatment of the present invention is directed to an apparatus defined as the second apparatus, wherein the circulating system comprises: a first discharged liquid storing section for storing a first discharged liquid collected and discharged to the vessel when at least part of the object already treated is cleaned; a second discharged liquid storing section for storing a second discharged liquid collected and discharged to the vessel when the inner wall surface of the vessel is cleaned; and a cleaning liquid supply means for supplying the first discharged liquid stored in the second discharged liquid storing section and the second discharged liquid stored in the second discharged liquid storing section, singly or in mixture, to the cleaning means.




In the fourth apparatus, since the first discharged liquid stored in the second discharged liquid storing section and the second discharged liquid stored in the second discharged liquid storing section, singly or in mixture, are supplied to the cleaning means, the once used cleaning liquid can be used with a good efficiency.




A fifth apparatus for a cleaning treatment of the present invention is directed to an apparatus defined as the fourth apparatus, wherein the cleaning liquid supply means supplies, for supplement, an unused cleaning liquid for cleaning at least part of the object already treated to at least one of the first discharge liquid storing section and the second discharge liquid storing section and supplies the stored liquids stored in the respective storing sections, single or in mixture, to the cleaning means.




In the fifth apparatus, since at least one of the first and second discharged liquid sections are supplemented with the unused cleaning liquid, that is a fresh cleaning liquid, to dilute the discharged liquids stored in the respective sections, and the discharged liquids, singly or in mixture, are supplied to the cleaning means, the once used cleaning liquid can be used without degrading a cleaning performance of the used cleaning liquid by any margin and the reuse of a cleaning liquid can be effected with a good efficiency.




A sixth apparatus of the present invention is directed to an apparatus defined as the second apparatus, wherein the circulating system comprises: a fresh liquid string section for storing an unused cleaning liquid; a first discharged liquid storing section for storing a first discharged liquid collected and discharged to the vessel when at least part of the object already treated is cleaned; a second discharged liquid storing section for storing a second discharged liquid collected and discharged to the vessel when the inner wall surface of the vessel is cleaned; and a cleaning liquid supply means for supplying the unused cleaning liquid stored in the fresh cleaning liquid storing section to at least one of the first discharged liquid storing section and the second discharged storing section and supplying to the cleaning means.




In the sixth apparatus, since the unused cleaning liquid stored in the fresh cleaning liquid storing section is added as supplement to at least one of the first and second discharged liquid sections and a discharged liquid from the at least one discharged liquid storing section supplemented with the unused cleaning liquid is supplied to the cleaning means, reuse of the cleaning liquid for cleaning a cup can be effected without any difficulty and without any degradation in a cleaning performance, so that a cleaning efficiency in cap cleaning is improved and a reliability of a cap cleaning operation is also increased.




A seventh apparatus of the present invention is directed to an apparatus defined as the second apparatus, wherein the circulating system comprises: a fresh cleaning liquid storing section for storing an unused cleaning liquid; a first discharged liquid storing section for storing a first discharged liquid collected and discharged to the vessel when at least part of the object already treated is cleaned; a second discharged liquid storing section for storing a second discharged liquid collected and discharged to the vessel when the inner wall surface of the vessel is cleaned; and a cleaning liquid supply means for supply the first discharged liquid stored in the first discharged liquid storing section, the second discharged liquid stored in the second discharged liquid storing section and the unused cleaning liquid stored in the fresh cleaning liquid storing section, singly of in mixture, to the cleaning means.




In the seventh apparatus, since the first discharged liquid stored in the first discharged liquid storing section, the second discharged liquid stored in the second discharged liquid storing section and the unused cleaning liquid stored in the fresh cleaning liquid storing section, singly of in mixture, are supplied to the cleaning means, the inside of the vessel can be cleaned with a good efficiency.




An eight apparatus of the present invention is directed to an apparatus defined as the third to seventh apparatus for a cleaning treatment, wherein the cleaning liquid supply means comprises: detecting means for detecting an amount of the cleaning liquid and discharged liquid stored in the respective storing sections; control means for controlling intake amounts of the cleaning liquid and discharged liquid based on the respective amounts detected by means of the detecting means.




In the eight apparatus, since the amounts of the cleaning liquid and discharged liquid stored in the respective storing sections are detected and the control means controls amounts of the cleaning liquid and discharged liquid which are fetched from the respective storing sections based on the amounts of the liquids detected by means of the detecting means, the amounts of the respective liquids being supplied to sections of the apparatus can be optimized.




A ninth apparatus of the present invention is directed to an apparatus defined as the third apparatus for a cleaning treatment, wherein the cleaning means comprises a first jetting unit for jetting the cleaning liquid toward the inner wall surface of the vessel in the vicinity of the object treated and a second jetting unit for jetting the cleaning liquid toward the inner wall surface in the vicinity of the discharge port remote from the object treated, and the circulating system supplies the discharged liquid, which is a used cleaning liquid, for the second jetting unit and the unused cleaning liquid for the first jetting unit.




In the ninth apparatus, since the discharged liquid, which is a used cleaning liquid, and the unused cleaning liquid are respectively to the second jetting unit and to the first jetting unit, the cleaning liquid can be used in the respective uses with a good efficiency.




A tenth apparatus of the present invention is directed to any of apparatuses defined as the first to ninth apparatuses, wherein the apparatus comprise a vessel for recovering a treatment liquid flowing out or flying out when the object is treated and the inner wall surface of the vessel has an ethylene fluoride based resin layer formed on the surface.




In the apparatuses, since the ethylene fluoride based resin layer is formed on the inner wall surface, the treatment liquid which flows out or flies out when the object is treated is less adhered.




An eleventh apparatus of the present invention is directed to any of apparatuses defined as the tenth apparatus, wherein the apparatus has an ethylene fluoride based resin layer formed on an inner surface of a recovering path inside the vessel in which the treatment liquid is recoverable.




In the eleventh apparatus, while part which is covered with an ethylene fluoride layer is limited, adhesion of the treatment liquid is minimized, so that, with a minimized usage amount of ethylene fluoride based resin, an effect that the reduced adhesion of the treatment liquid is achieved.




An aspect of the present invention is directed to an apparatus for a cleaning treatment of a cup in a coating mechanism, comprising: a rotary cup with a cover which is rotatable, and which encloses a holding means for holding an object treated and the side and bottom portions of the object to be treated; a stationary cup which encloses the side and bottom portions of the covered rotary cup; and a rectifying plate covering the object treated at a position thereabove, which is mounted inside the covered rotary cup, the apparatus comprising: a first nozzle for supplying a cleaning liquid on the rectifying plate by way of a supply hole bored in the middle of the cover of the covered rotary cup; a second nozzle, which is located under the holding means, for supplying the cleaning liquid toward the lower surface of the peripheral portion of the rectifying plate, the inner side surface of the covered rotary cup and the bottom surface of the stationary cup.




In the apparatus of the present invention, it is preferred that the apparatus further comprises a third nozzle, which is located inside the stationary cup, for supplying the cleaning liquid toward a lower part of the outside surface of the covered rotary cup and the inner side surface of the stationary cup. In this case, a lower part of the stationary cup is so formed that the inner surface is bent outwardly and the bottom is open and the cleaning liquid is supplied toward to the bent portion of the inner side surface of the stationary cup from the third nozzle.




An aspect of the present invention is directed to a method for a cleaning treatment of a cup in a coating mechanism comprising a rotary cup with a cover which is rotatable, and which encloses a holding means for holding an object treated and the side and bottom portions of the object treated; a stationary cup which encloses the side and bottom portions of the covered rotary cup; and a rectifying plate covering the object treated at a position thereabove, comprising the steps of: supplying a cleaning liquid through the middle of the cover of the covered rotary cup toward the rectifying plate while rotating the covered rotary cup to supply the cleaning liquid to the lower surface of the cover with the help of an centrifugal force; and at the same time supplying the cleaning liquid toward the lower surface of the outer periphery of the rectifying plate, the inner side surface of the covered rotary cup and the bottom surface of the stationary cup.




In the method of the present invention, it is preferred that the cleaning liquid is supplied on a lower part of the outside surface of the covered rotary cup and the inner side surface of the stationary cup.




In the method of the present invention, it is also preferred that the cleaning liquid is supplied toward the rectifying plate from the middle of the cover of the covered rotary cup, while rotating the covered rotary cup at a first rotational speed; the cleaning liquid is supplied toward the lower surface of the outer peripheral portion of the rectifying plate and the inner side surface of the covered rotary cup, while rotating the covered rotary cup at a second rotational speed larger than the first rotational speed; and the cleaning liquid is supplied on the bottom surface of the covered rotary cup, while rotating the covered rotary cup at a third rotational speed smaller than the first rotational speed, wherein the speeds may be set in such a manner that, for example, the first rotational speed is in the range of from 350 to 650 rpm, the second rotational speed is in the range of from 700 to 1300 rpm and the third rotational speed is in the range of from 14 to 26 rpm.




According to the present invention, in a condition that the covered rotary cup is continued to rotates, the cleaning liquid is supplied toward the rectifying plate from the middle of the cover of the rotary cup and at the same time the cleaning liquid is supplied on a lower surface of the outer peripheral portion of the rectifying plate, the inner side surface of the covered rotary cup and the bottom of the stationary cup and thereby the cleaning liquid supplied from the middle of the cover of the rotary cup is sprayed outwardly by a centrifugal force caused by the rotating rectifying plate to remove a coating liquid adhered on the lower surface of the cover, and the coating liquid adhered to the lower surface of the outer peripheral portion of the rectifying plate, the inner side surface of the rotary cup and the bottom surface of the stationary cup is removed by the cleaning liquid directly supplied thereto.




Besides, the coating liquid adhered on a lower surface of the outer peripheral portion of the rotary cup and the inner side surface of the stationary cup can be removed by supplying the cleaning liquid thereon. In this case, the lower part of the inner side surface of the stationary cup can be formed in such a manner that the inner side surface of the stationary cup is bent outwardly and thereby there can be produced a stagnant space of an air stream flowing a gap between the rotary cup and stationary cup, so that the coating liquid is held up in the stagnant space and prevented to flow back upwardly. Moreover, the coating liquid adhered on the stationary cup can be removed by supplying the cleaning liquid from the third nozzle toward the bent portion of the inner side surface of the stationary cup.




When the cleaning liquid is supplied toward the rectifying plate from the middle of the cover of the covered rotary cup, while rotating the covered rotary cup at the first rotational speed, for example in the range of 350 to 650 rpm, the cleaning liquid is forced impinge on a lower surface of the outer peripheral portion of the cover by an centrifugal force caused by a rotation of the rectifying plate which rotates together with the rotary cup and thereby the coating liquid adhered on the lower surface of the cover can be removed. When the cleaning liquid is supplied toward a lower surface of the outer peripheral portion of the rectifying plate and the inner side surface of the covered rotary cup while rotating the covered rotary cup at a rotational speed, for example in the range of 700 to 1300 rpm, the cleaning liquid can be supplied with a good efficiency over a broad surfaces covering the lower surface of the outer peripheral portion of the rectifying plate and the inner side surface of the rotary cup. When the cleaning liquid is supplied on the bottom surface of the covered rotary cup and a target area of a stream thereof is moved from the middle to the outer peripheral, while rotating the covered rotary cup at a rotational speed, for example in the range of 14 to 26 rpm, the coating liquid adhered on the bottom can be removed.




Additional objects and advantages of the invention will be set forth in the description which follows and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and combinations particularly pointed out in the appended claims.











BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING




The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments give below, serve to explain the principles of the invention.





FIG. 1

is a perspective view showing a construction of a LCD substrate treatment system according to an embodiment of the present invention;





FIG. 2

is a view showing a structure of a resist coating/removing apparatus of a LCD substrate treatment system;





FIG. 3

is a sectional view showing a coating mechanism of the resist coating/removing apparatus;





FIG. 4

is an enlarged sectional view of a vessel (a treatment room, a rotary cup and a drainage cup) of the coating mechanism of

FIG. 3

;





FIG. 5

is a view showing coating of ethylene fluoride based resin on surfaces in the vessel of

FIG. 4

;





FIG. 6

is a schematic perspective view showing the top surface of a mounting table;





FIG. 7

is an enlarged view in section of a main portion of

FIG. 6

;





FIG. 8

is a sectional view of an edge removing mechanism;





FIG. 9A

is a plan view showing nozzle holes for a front surface of the edge removing mechanism of

FIG. 8

;





FIG. 9B

is a plan view showing nozzle holes for a rear surface of the edge removing mechanism of

FIG. 8

;





FIG. 10

is a view showing a first apparatus for a cleaning treatment;





FIG. 11

is a view showing an example of modification of the vessel.





FIG. 12

is a view showing another example of modification of the vessel;





FIG. 13

is a view showing still another example of modification of the vessel;





FIG. 14

is a view showing a second apparatus for a cleaning treatment;





FIG. 15

is a view showing a third apparatus for a cleaning treatment;





FIG. 16

is a schematic plan view showing a resist coater equipped with a fourth apparatus for a cleaning treatment;





FIG. 17

is a schematic sectional view showing the fourth apparatus of the present invention;





FIG. 18

is an enlarged sectional view showing a main portion of the fourth apparatus;





FIG. 19

is a schematic sectional view showing a cleaning section in an operational condition;





FIGS. 20A

,


20


B and


20


C are schematic sectional views showing different kinds of a second cleaning nozzle; and





FIGS. 21A and 21B

are schematic sectional views showing different kinds of a third cleaning nozzle.











DETAILED DESCRIPTION OF THE INVENTION




Embodiments of the present invention will be in detail in reference to the attached drawings.





FIG. 1

is a view showing a construction of a coating/developing system for a LCD substrate (hereafter referred to as LCD substrate treatment system) according to a first embodiment of the present invention.




As shown in the figure, the LCD substrate treatment system comprises: a loading section


90


in which an object to be treated, for example a rectangular LCD glass substrate G (hereinafter referred to glass substrate G) is transported in or out, a first treatment section


91


in which the glass substrate G is treated, a second treatment section


92


which is connected with the first treatment section


91


with an intermediate section


93


lying therebetween and a transfer section


94


for feeding or receiving a glass substrate G between the second treatment section


92


and another apparatus, for example an exposure apparatus


95


.




In the loader


90


, a cassette stage


98


is installed. A plurality of cassette


96


,


97


are mounted on the cassette stage


98


, a plurality of untreated glass substrates G are accommodated in the cassette


97


. A pincette


99


for transporting in or transporting out unused glass substrates is disposed in the loading section


99


.




The first treatment section


91


comprises: a brush cleaning apparatus


120


, a jet water cleaning apparatus


130


, an adhesion treatment apparatus


105


, a cooling treatment apparatus


106


, a pair of resist coating/removing apparatuses


107


,


108


. In the central passage in the first treatment section


91


,


80




a


is disposed in a manner that it is free to run or stop.




The second treatment section


92


comprises a plurality of heating treatment apparatuses


109


; and a pair of developing apparatuses


110


. In the central passage in the second treatment


92


, a main arm


80




b


is equipped in a manner that it is free to run or stop. In the second treatment section


92


, a pincette


112


for transporting in or transporting out a glass substrate G is installed. In an intermediate section


93


, a table


93




a


for forwarding or receiving a glass substrate G is installed. In a forwarding/receiving section


94


, a table


113


for forwarding or receiving a glass substrate G is installed. The exposure apparatus


95


is used to expose a fine pattern on a resist film.




As shown in

FIG. 2

, each of the resist coating/removing apparatuses


107


,


108


comprises: a coating mechanism


1


for coating the surface of a glass substrate G with a coating liquid, for example a resist liquid, which is supplied from a coating liquid supply nozzle


1




a


; an edge removing mechanism


2


for removing an unnecessary coating film formed on the peripheral portion of the glass substrate G, wherein the coating mechanism


1




a


and the edge removing mechanism


2


are disposed in a adjoining manner, in other words both mechanisms


1


and


2


are contained in the same atmosphere as one body; a cleaning treatment apparatus


4


as a circulating system in which the cleaning liquid used in the edge removing mechanism


2


, for example a thinner which is a solvent for a resist liquid, is recovered and the thinner is circulated for cup cleaning in the coating mechanism


1


; and a transportation mechanism


3


for transporting the glass substrate G already coated with the resist by the coating mechanism


1


to the edge resist removing mechanism


2


. In the edge removing mechanism


2


, guide rails


53


are disposed in an extending manner in an X or Y direction, a plurality of sliding members


54


mounted on the guide rail


53


in a manner that the sliding member


54


is free to slide. A sliding member


54


comprises: a wire; a chain; a belt; a ball screw; and an moving mechansm using a stepping motor and an air cylinder and is constructed so that it can be freely movable in an X or Y direction. Each slide member


54


is mounted with a resist removing nozzle


51


which is a constituent of the edge removing mechanism


2


. Moreover, in the vicinity of each of cross sections of guide rails


53


there is located a sensor


55


which detects an adjacent position of a resist removing nozzle


51


so that adjacent resist removing nozzles


51


are not mutually interfere, that is do not collide with each other. With this sensor, it is detected that the adjacent removing nozzle


51


approaches to another resist removing nozzle


51


, which detecting signal is transmitted to a control section, which is later described, and driving of the moving mechanism is stopped by a control signal from the control section, so that adjacent resist removing nozzles


51


are prevented from an interference, that is collision therebetween.




As shown in

FIGS. 2 and 3

, the coating mechanism


1


mainly comprises: a spin chuck


10


, which is rotatable in a horizontal plane (θ direction), and on which a glass substrate G is vacuum-chucked by a vacuum apparatus not shown; a rotary cup


12


having a cylindrical form with a ceiling and bottom with respective openings, which further comprises a treatment room


20


which encloses the upper portion of the spin chuck


10


and its outer peripheral portion; a cover


16


which is freely mounted/demounted so that a opening


12




a


of the rotary cup


12


is freely closed/opened; and a drainage cup


14


having a shape of a hollow ring, which is disposed in a surrounding manner outside the rotary cup


12


. The drainage cup


14


is to receive and collect a waste from the rotary cup


12


. The treatment room


20


, rotary cup


12


, cover


16


and drainage cup


14


constitute a vessel for recovering a treatment liquid or a cleaning liquid.




The spin chuck


10


is freely rotatable in a horizontal plane about a rotary shaft


22


by rotation of the shaft


22


which is driven by a drive motor


21


disposed in a lower position and besides shiftable in vertical directions by the rotary shaft


22


which is connected to a vertical shift cylinder


23


, and driven by the vertical shift cylinder


23


. In this case, the rotary shaft


22


is slidably connected to a spline bearing


27


which is fittingly inserted in a rotary inner cylinder


26




a


which is in turn inserted rotatably in a stationary collar


24


with the help of a bearing


25




a


therebetween. A driven pulley


28




a


is mounted on the spline bearing


27


and a belt


29




a


is extended between the driven pulley


28




a


and a driving pulley


21




b


which is fixed on a drive shaft


21




a


of a drive motor


21


. Accordingly, the spin chuck


10


is rotated by rotation of the rotary shaft


22


which is rotated by the drive motor


21


with the help of the belt


29




a


as an intermediate. In a lower portion than the rotary shaft


22


there are located a cylindrical tube not shown. In the cylindrical tube the rotary shaft


22


is connected to the vertical shift cylinder


23


through a vacuum seal


30


and the rotary shaft


22


is driven to move vertically by being driven by the vertical shift cylinder


23


.




The rotary cup


12


is indirectly mounted on the upper end of a rotary outer cylinder


26




b


with a connecting cylinder


31


fixedly mounted on the upper end of the rotary outer cylinder


26




b


in a direct relation, the rotary outer cylinder


26




b


being mounted on the outer peripheral surface of the stationary collar


24


. The rotary cup


12


and the spin chuck


10


are rotatable relative to each other with a bearing


32


having a sealing function between the bottom


12




b


of the rotary cup


12


and the lower surface of the spin chuck


10


. The driving from the drive motor


21


is transferred to the rotary cup


12


with the help of the belt


29




b


which extends between the driven pulley


28




b


, which is fixedly mounted on the rotary outer cylinder


26




b


, and the drive pulley


21




b


mounted on the drive shaft


21




b


of the drive motor


21


. In this case, a diameter of the driven pulley


28




b


is made so as to be equal to that of the driven pulley


28




a


which is fixedly mounted on the rotary shaft


22


and the belts


29




a


,


29




b


are engaged with the same motor


21


and thereby the rotary cup


12


and the spin chuck


10


are rotated at the same speed. A labyrinth seal section (not shown) is provided between the opposed surfaces of the stationary collar


24


and the rotary inner cylinder


26




a


and dust is prevented from invasion into the inside of the rotary cup


12


from a driving system located in a lower portion when the rotary cup


12


is working. Different rotational speeds can be selected by adopting different diameters of the driven pulleys


28




a


,


28




b.






As shown in

FIGS. 3 and 4

, the rotary cup


12


has a tapered inner side wall and the inner diameter of the rotary cup


12


is decreased upwardly. The reason why is because an air stream supplied from an air supply port


34


which is bored in the middle portion of the cover


16


, when the rotary cup is working, flows on and along the rectifying plate


33


, which is arranged under the cover


16


, further flows downwardly along the tapered side wall and then is discharged from the exhaust port


35


which are disposed at proper positions in the lower peripheral portion, that is on the lower portion of the side wall.




With such circumstances wherein the air supply port


34


and exhaust port


35


are provided, the air stream from the air supply port


34


into the treatment room


20


flows out from the exhaust port


35


to the outside and thereby it is prevented that the treatment room is reduced in excess of a necessary negative pressure while the rotary cup


12


is rotated. Besides, a large force is unnecessary to open the cover


16


from the rotary cup


12


after the treatment is terminated and the cover


16


can take away with ease.




On the other hand, as shown in

FIG. 4

, a ring like passage


14




a


is formed in the drainage cup


14


and exhaust ports


36


are formed at proper positions on the outer wall of the ring like passage


14




a


(for example, at four positions along a periphery) and the exhaust ports


36


are connected with an exhausting apparatus not shown. Furthermore, exhaust passages


37


are formed in a radiating manner in the upper portion of the inner wall of the drainage cup


14


, the exhaust passages


37


being communicated with the exhaust ports


36


(see FIG.


3


).




In such a manner, since the exhaust ports


36


are provided on the outer side wall of the drainage cup


14


and the exhaust passages


37


are formed in the upper portion of the inner side wall of the drainage cup


14


, a mist flying away under an influence of a centrifugal force and flowing into the drainage cup


14


through the exhaust ports


35


when a rotational treatment is performed is prevented from flying upwardly to an upper portion of the rotary cup


12


and the mist is discharged through the exhaust ports.




The ring like passage


14




a


is partitioned by the erected wall at the bottom of the drainage cup


14


and a depending wall


14




c


at the ceiling portion of the drainage cup


14


to form a detour and exhaust an air in a uniform manner and besides drainage holes


14




e


are formed on the bottom between the walls


14




b


and


14




a


in a proper distance along a periphery.




While the cover


16


is required to be fixed to the opening


12




a


of the rotary cup


12


and to be rotated in a body during a rotational treatment, for example, fixed pins (not shown) planted on the top surface of the rotary cup


12


and engaging holes in the corresponding positions of the cover


16


(not shown) to be engaged with the fixed pins are provided and can be mutually engaged with each other so as to keep the cover


16


and rotary cup


12


fixed to each other.




When the cover


16


is opened or closed, as shown with fictitious lines in

FIG. 3

, a robot arm


40


is inserted under an expanded head


18


protruded on the upper surface of the cover


16


, besides engage pins protruding from the robot arm


40


are fittingly inserted into engaging grooves


18




a


and thereafter the robot arm


40


is moved vertically or laterally to move the cover


16


. In order to facilitate the positioning between the engaging grooves


18




a


in the expanded head


18


and the engaging pins


41


of the robot arm


40


when the cover is opened, and the positioning between the fixed pins and the engaging holes when the cover


16


is closed, the positioning in both cases can be effected by controlling an angle of rotation of a servo motor as the drive motor


21


.




On the other hand, as shown in

FIGS. 3 and 4

, there are mounted a thinner supply nozzle


15




a


as a first jet section for jetting a cleaning liquid, for example an unused thinner toward the inner wall surface


12




c


of the rotary cup


12


in the treatment room


20


. There are mounted a thinner supply nozzle


15




c


as a second jet section on the horizontal strip


14




f


of the bottom of the drainage cup


14


extending under and along the rotary cup


12


for jetting (supplying) a thinner toward the lower part of the outer side surface of the rotary cup


12


and the inner side wall


14




c


of the drainage cup


14


. A thinner supply nozzle


15




a


as a second jet section is mounted on the wall


14




c


of the drainage cup


14


for jetting a cleaning liquid, for example a recycled thinner, toward the outer side of the rotary cup


12


. Moreover, a thinner supply nozzle


15




b


as the second jet section is mounted on the wall


14




b


of the drainage cup


14


for jetting a cleaning liquid, for example a recycled thinner toward the outer side of the wall


14




c


and the inner side of the wall


14




b


. These thinner supply nozzles


15




a


,


15




b


,


15




c


are mounted along peripheries at a proper distance.




The rotary cup


12


and the drainage cup


14


are made of, for example a stainless sheet (SUS


304


) and the like. While this plate is selected in order to form a coating film made of one of a specified materials shown in the following table, as a substrate for a coating portion, it is not restricted to SUS


304


but, for example, a resin or a metal may be used instead.




As shown in

FIG. 5

, surfaces in the treatment room


20


and the ring like passage


14




a


which surfaces are contacted with a treatment liquid or a cleaning liquid (shown as a portions on whose surfaces short oblique lines are hatched), for example the inner wall surfaces


12




a


,


12




b


of the rotary cup


12


, the inner surface of the cover


16


, the front and rear surfaces of the rectifying plate


33


, wall surfaces inside the ring like passage


14




a


of the drainage cup


14


(both surfaces of each of walls


14




b


,


14




c


, the inner surface of the bottom


14




d


and the inner surface of the drainage


14




e


and the like) are coated with a film of a thickness about 60 μm made of such a coating material as ethylene fluoride based resin, for example polytetrafluoroethylene (PTFE).















TABLE 1













Contact Angle (°)




Adhesion Test of















No. of




Material





Resist TFP-670 (15CP)




Resist (Film






Example




(coating)




Pure Water




PGMEA




Thickness μm)



















1




SUS 304




{circle around (12)} 49.4




{circle around (12)}   17.0




{circle around (12)}




Resist Adhered







Adrasive




(22.8 + 22.6)






(7.1 μm)






2




SUS 304




 {circle around (5)} 103.5




 {circle around (7)}   55.6




 {circle around (1)}




4 to 5 Particles







Affixed Teflon




(51.7 + 51.8)






Adhered (−)







Tape






3




PFA




 {circle around (8)} 88.6




 {circle around (8)}   55.0




 {circle around (1)}




4 to 5 Particles








(44.9 + 43.7)






Adhered (−)






4




PTFE




 {circle around (7)}  99.7




 {circle around (6)}  58.7




 {circle around (6)}




11 Particles








(50.3 + 49.4)






Adhered (−)






5




SUS 304




 {circle around (6)} 101.8




 {circle around (6)}  57.9




 {circle around (1)}




4 Particles







PTFE + PFA




(50.4 + 51.4)






Adhered (−)







(100 μm)






6




SUS 304 PTFE




 {circle around (1)} 125.3




 {circle around (2)}   60.4




 {circle around (1)}




4 to 5 Particles







(60 μm)




(63.1 + 62.3)






Adhered (−)






7




SUS 304 Tough Coat




 {circle around (2)} 121.3




 {circle around (3)}   59.6




 {circle around (7)}




50 to 60 Particles







(40 μm)




(60.3 + 61.3)






Adhered (−)






8




SUS 304 6F (FEP)




 {circle around (3)} 112




 {circle around (4)}   59.2




 {circle around (1)}




3 Particles







(250 μm)




(54.7 + 57.3)






Adhered






9




SUS 304




{circle around (10)} 80.4




{circle around (11)}   22.6




 {circle around (9)}




Resist Adhered







2F(60 μm)




(40.4 + 40.4)






(4.7 μm)






10




SUS 304




 {circle around (4)} 77.0




 {circle around (9)}  37.6




{circle around (11)}




Resist Adhered







Silicone(60 μm)




(38.3 + 38.7)






(6 μm)






11




Aluminum-toughram




 {circle around (4)} 109.1




 {circle around (1)}  61.1




 {circle around (8)}




Resist Adhered







(30 μm)




(54.3 + 54.8)






(8.1 μm)






12




Aluminum electroless




{circle around (11)} 72




{circle around (10)}   25.4




{circle around (10)}




Resist Adhered







Ni plating




(35.8 + 36.2)






(5.3 μm)
















Magic Ink Stain
















⊚:




well wiped




Chemical Resistance























off






Residue







Coating







◯:




wiped off




PEGMEA




Developer




Nozzle




MEK




OK73





Particle






No. of




Δ:




trace left




9/17




9/12




9/12




9/12




9/12





Size






Example




X:




not erased




START




START




START




START




START




Hardness




¥/dm


2)











1




{circle around (8)}




X









































2




{circle around (2)}














































3




{circle around (1)}


































less than



















3H






4




{circle around (4)}


































less than



















3H






5




{circle around (3)}


































less than




410














3H






6




{circle around (6)}




Δ





























less than




240














3H






7




{circle around (8)}




X





























less than




240














3H






8




{circle around (6)}




Δ





























less than




570














3H






9




{circle around (8)}




X









9/17









9/17









4H




240










X





X






10




{circle around (8)}




X




9/21




X




9/17




9/17




9/17




less than




240









X





X




X




X




3H






11




{circle around (7)}




X









9/13



















5H




300










X






12




{circle around (8)}




X









9/13



















5H




150










X














Table 1 shows results of an adhesion test (contact angle), resist attachment test, a wipe-off test (magic ink stain), a chemical resistance test and a hardness test conducted on examples of combinations of plate materials and coating materials (Examples 1 to 12) and the table includes prices corresponding to respective test results. As can be seen from the results of the table, the best combination of a plate material and a coating material is that of Example 6.




The example 6 is an example in which PTFE as a coating material was coated as film with a thickness of 60 μm on the surface of SUS


304


as a plate material. In this case, an angle of contact of pure water has shown 25.3°, which is the largest, resist adhesion is as small as 4 to 5 particles and a degree of resist adhesion (degree of close contact) is very low, compared with other examples.




Other than the example 6, a combination of the example 5 can be used, in which a copolymer of PTFE and ethylene (PTFE+PFE) is coated as film of a thickness of the order of 100 μm on SUS


304


, results shows that an adhesion test (contact angle of pure water) is inferior to the example 6, but a resist attachment test and a wipe-off test are better than the example 6. That is, it has been confirmed that the cases where inner wall surfaces of the treatment room


20


and the ring like passage


14


are coated with an ethylene resin has a small amount of residual resist on coated portions and show better results.




The edge removing mechanism


2


shown in

FIG. 2

comprises: a mounting table


50


for vacuum-holding a glass substrate by means of a vacuum apparatus not shown and four removing nozzles


51


for jetting a cleaning liquid, for example a thinner as a resist solvent on the upper and lower surfaces of the outer periphery of the four sides of the glass substrate held by the mounting table


50


.




As shown in

FIG. 6

, a plurality of, for example, nine copying pads


52


holding the glass substrate G are attached on the upper surface of the mounting table


50


.




As shown in

FIG. 7

, a pad


52


is constructed of an oil seal


52




c


having the shape of almost a crown fixed by a ring-nut


52




b


for pressing by way of a packing


52




a


in a stepped recess


50




b


located along a periphery outside a vacuum hole


50




a


formed in the mounting table


50


in a manner to cover the vacuum hole


50




a


; and a top pad


52




e


having a suction hole


52




f


in the central portion which pad is engaged with an upper portion


52




d


of the oil seal


52




c


in a movable manner. With such a construction, when the glass substrate G is mounted on the top pad


52




e


and a vacuum apparatus is driven for suction, the top pad


52




e


is forced to a close contacting condition while conforming with an inclination or deformation of the glass substrate G to vacuum hold the glass substrate G with security.




As shown in

FIG. 8

, a removing nozzle


51


is constructed of: an upper horizontal strip


56




a


which covers the upper surface of the peripheral portion of the glass substrate G; and a jetting head


56


having the shape like a Greek π in section comprising a lower horizontal strip


56




b


protruding outwardly of the upper horizontal piece


56




a


. In the upper horizontal piece and lower horizontal strip


56




b


and the jetting head


56


, thinner supply path


56




c


for removing a resist on the front surface and a thinner supply path


56




d


for removing a resist on the rear surface. A plurality of nozzle holes


51




a


for cleaning the front surface and a plurality of nozzle holes


56




b


are respectively connected to the thinner supply paths


56




c


and


56




b


. In a vertical portion


56




e


of the jetting head


56


, a discharged liquid path


56




f


, which is connected with a recovering pipe


60


later described, is disposed along a central line C. The opening


56




g


near the side of a substrate edge portion of the discharged liquid path


56




f


is formed in a shape having a taper and in such a manner that a diameter of the discharged liquid path


56




f


increases in width toward the opening.




As shown in

FIG. 9A

, a plurality of nozzle holes


51




a


are arranged at a proper distance on a line perpendicular to the central line C of a removing nozzle


51


. In this case, the nozzle holes


51




a


are disposed at positions other than the central line C and inside of the expanding tapered opening


56




g


of the discharged liquid path


56




f.






On the other hand, as shown in

FIG. 9B

, a plurality of nozzle holes


51




b


are arranged on a straight line opposed to the nozzle holes


51




a


at positions with a proper distance therebetween in such a manner that the nozzle holes


51




a


and


51




b


do not interfere therebetween and inside the opening of the expanding tapered opening


56




g


. The reason why the nozzle holes


51




a


and


51




b


are arranged in an offset manner is that, while jet streams from the nozzles


51




a


and


51




b


collide against each other, a thinner is scattered around and the scattered thinner is then attached on a resist film of the surface of the glass substrate G, which gives a wrong influence such as non-uniformity of a film thickness of the resist film, it is to prevent such a wrong influence. Besides, with the expanding tapered opening


56




g


inside which the nozzle holes


51




a


and


51




b


are disposed, thinners fed or supplied from the nozzle holes


51




a


and


51




b


can be recovered into the covering pipe


60


through the discharged liquid


56




f


with a good efficiency without a thinner sprayed away outwardly.




As shown in

FIG. 10

, the apparatus for a cleaning treatment


4


comprises: a recovering pipe


60


recovering a thinner jetted toward both surfaces of a glass substrate G already having a resist film formed by a resist removing nozzle


51


through a discharged liquid path


56




f


of resist removing nozzles


51


; a suction mechanism


61


connected with the recovering pipe


60


with a selector valve


75


in the way therebetween; a mist tap


62


as a gas/liquid separation means for effecting gas/liquid separation from a mixture of a thinner and air recovered by the suction mechanism


61


; an edge remover tank (hereinafter referred to as ER tank


70


) as a first discharged liquid storing section for storing a thinner A


1


, which is already used, and which is separated from the mist trap


62


; a valve


64




a


connected to the ER tank


70


with a supplement supply pipe


63




a


therebetween; a fresh liquid tank


71


storing an unused thinner A


0


(a fresh liquid) and connected to the valve


64




a


; a thinner re-supply pipe


65


supplying a used thinner A


1


(for a recycle use) to thinner supply nozzles


15




a


to


15




c


with the valve


64




b


interposing therebetween from the ER tank


70


; a fresh liquid supply pipe


66


supplying the unused thinner A


0


to removing nozzles


51


from the fresh liquid tank


71


; a DR tank as a second discharged liquid storing section storing a thinner A


2


(discharged liquid) which is already used (a recycle use) and which is discharged from drainage holes


14




e


; a supplemental supply pipe


63




b


supplementing with the unused thinner A


0


(a fresh liquid) from the fresh tank


71


with a connection between the DR tank


72


and the valve


64




a


; a valve


64




c


interposed between the DR tank


72


and the thinner re-supply pipe


65


; a liquid level sensor


74


installed in the tanks


70


,


71


,


72


detecting the liquid level of the thinner stored in the respective tanks; and a control section


68


in such a manner that valves


64




a


to


64




c


and the selector valve


75


are respective controlled based on the information on the liquid levels detected by the liquid level sensor


74


, thereby intakes of the thinner of the respective tanks


70


,


71


, and


72


and further a moving mechanism not shown is controlled based on the detecting information in the sensor


55


detecting the position of the removing nozzles


51


.




The ER tank


70


and the DR tank


72


are connected with the thinner supply nozzles


15




a


to


15




c


with the help of a thinner re-supply pipe


65


, an inert gas, for example nitrogen gas (hereinafter referred to as N2 gas) are supplied from an inert gas supply source not shown to the tanks


70


,


72


, the thinners A


1


, A


2


in the tanks


70


,


72


are jetted from the thinner supply nozzles


15




a


to


15




c


to the inside of the treatment room


20


, the inner and outer wall of the rotary cup


20


and the wall surfaces of the drainage cup


14


by a pressure of N2 gas in the tanks


70


,


72


, while a degree of opening of the valves


64




b


,


64




c


is adjusted. The thinners A


1


, A


2


may be supplied by the use of pumps instead of N2 gas to the thinner supply nozzles


15




a


to


15




c.






The liquid level sensor


74


detects liquid levels of the ER and DR tanks


70


,


72


when the thinners therein are decreased to a level more or less than the predetermined quantities and detected information is transmitted to the control section


68


as a liquid level detecting signal and degrees of opening of the valves


64




a


to


64




c


are controlled based on the liquid level detecting signal by the control section


68


. The control section


68


controls the selector valve


75


to discharge an unused thinner at the beginning of recovery (a thinner with a resist of a relatively higher concentration) from the removing nozzles


51


in the edge removing mechanism


2


through the discharged liquid pipe


76


and thereafter the control section


68


switches flow to another direction to send the thinner to the side of suction mechanism


61


, whereby recovery is conducted on the thinners which is suitable for recovery.




Here, the outline of operation of the LCD substrate treatment system will be described.




In this LCD substrate treatment system, a used glass substrate G accommodated in a cassette


96


are taken out by the take-in pincette of the loading section


90


, the glass substrate G is transferred to the main arm


80


which moves on the transport path


102


of the first treatment section


91


, and transported into the brush cleaning apparatus


120


. The glass substrate G cleaned in this brush cleaning apparatus


120


is subsequently cleaned by a high pressure jet water in the jet water cleaning apparatus


130


. Thereafter, the glass substrate G is subjected to a process in which the glass substrate G is made hydrophobic in the adhesion treatment apparatus


105


, cooled by the cooling treatment apparatus


106


and thereafter a resist film is formed by the coating mechanism


1


in the resist coating/removing apparatuses


107


,


108


. Subsequently, the glass substrate is transferred to the adjacent the edge removing mechanism


2


side to remove an unnecessary part of the resist film in the peripheral area of the glass substrate G by the edge removing mechanism


2


. Accordingly, in the following stages, when the glass substrate G is transported out, the main arms


80




a


,


80




b


and the like are not attached with a resist, since the resist film in the peripheral area is removed. A discharged liquid which is used for removing unnecessary resist in the edge removing mechanism


2


and is contaminated with a resist, is recovered into the mist trap


62


by way of the recovering pipe


60


, and a liquid ingredient only, that is a thinner, is recovered by subjecting the recovered discharged liquid to a gas/liquid separation process and is stored in the ER tanks


70


. The thinner stored in the ER and DR tanks


70


,


72


are again used to clean cups of the resist applying/removing apparatuses


107


,


108


using the apparatus for a cleaning treatment


4


.




The glass substrate G from which unnecessary resist has been removed in the resist coating/removing apparatuses


107


,


108


is tranferred to the heat treatment apparatus


109


to subject the glass substrate G to a baking treatment by heating, and thereafter a predetermined pattern is exposed on the surface of the glass substrate G in the exposure apparatus


95


. The exposed glass substrate G is accepted by the main arm


80




b


moving along the transport path


102




a


of the second treatment section


92


, transferred into the developing apparatus


110


, after being developed the glass substrate G is rinsed with a rinse liquid to wash out the developer and then a developing treatment is finished. The glass substrate G already treated in the developing treatment is accommodated in the cassette


97


in the loading section


97


and transported out to next treatment step.




Next, Actions (cleaning and circulation operations) in the apparatus


4


for a cleaning treatment above mentioned will be described.




A glass substrate G subjected to a coating treatment in the coating mechanism


1


is transported on the mounting table


50


of the edge removing mechanism


2


by the transport mechanism


3


to be held by vacuum suction.




The moving mechanism of the removing nozzles


51


is driven to move the removing nozzles


51


arranged along the sides in a direction of X or Y and at the same time the thinner A


0


is supplied to the nozzle holes


51




a


,


51




b


from the fresh liquid tank


71


to be jetted in order to dissolve and remove the unnecessary resist attached on both surfaces of the peripheral portion of the glass substrate G. The thinner used for cleaning is made to flow into the recovering pipe


60


on an air stream produced by suction of the suction mechanism


61


and recovered into the mist trap


62


through the selector valve


75


and the suction mechanism


61


. In this case, the thinner used at the beginning of cleaning is discharged from the discharged liquid pipe


76


by switching of the selector valve


75


.




The thinner (a discharged material) recovered in the mist trap


62


is mixed with air (gas) and therefore the air (gas) only is removed (exhausted) to the outside by an exhausting function of the mist trap


62


and the liquid ingredient only is stored in the ER tank


70


by its own weight.




When the stored quantity of a thinner in the ER tank


70


is increased, a liquid level of the thinner goes upward and the level is detected by the liquid level sensor


74


, which is disposed at an upper portion of the ER tank


70


, the information is transmitted to the control section


68


.




The control section


68


sends a control signal to the valve


64




b


to open the valve


64




b


and at the same time N2 gas is supplied into the ER tank


70


from the N2 supply source not shown and the thinner A


1


in the ER tank


70


is supplied through the thinner re-supply pipe


65


to the thinner supply nozzles


15




a


to


15




c


by a pressure increased by the supplied N2 gas, the thinner A


1


is jetted (supplied) through the thinner supply nozzles


15




a


to


15




c


on the outer side surface of the rotary cup


12


and the inner side surface of the drainage cup


14


to effect a cup cleaning.




In such operations performed as mentioned above, traces of the resist attached on the walls of the treatment room


20


, the rotary cup


12


and drainage cup


14


are dissolved and removed, the attachment of the resist is made by the flying away during the time of a resist coating treatment. Since PTFE is applied as coating on the walls of the treatment room


20


, rotary cup


12


, and drainage cup


14


and a resist is less attached, compared with a conventional case, a running interval of a cleaning treatment between the wall cleanings can be increased.




The thinner discharged when a cup cleaning is carried out is stored into the DR tank


72


after being discharged through the drainage holes


14


of the drainage cup


14


.




When quantities of the thinners A


1


, A


2


in the ER tank


70


and DR tank


72


are decreased, the facts are detected by the level sensors


74


. The valve


64




a


is controlled by the control section


68


, and at the same time N2 gas is supplied to the fresh tank


71


from the N2 supply source not shown to build up a pressure in the fresh tank


71


, an unused thinner A


0


in the fresh liquid tank


71


is supplied for supplement to the ER tank


70


and DR tank


72


through the supplemental supply pipe


63




a.






In such a manner as described above, a cleaning efficiency of a cup cleaning is improved and a reliability of an apparatus for a cleaning treatment is also increased without any difficulty in a cup cleaning.




According to the first embodiment of a LCD substrate treatment system, the thinner A


1


which is used for removing the unnecessary resist attached to the peripheral portion of the glass substrate G in the edge removing mechanism


2


is stored in the ER tank


70


, the thinner A


2


which is used for a cup cleaning is stored in the DR tank


72


, the thinners A


1


, A


2


stored in the tanks


70


,


72


are re-used for a cup cleaning and thereby thinners which have been conventionally discharged can be effectively used, so that loss in usage of thinner is avoided and a running cost is reduced.




Moreover, in the same treatment system including the coating mechanism


1


and edge removing mechanism


2


, since the thinner used in the edge removing mechanism


2


is re-used in a cup cleaning in the coating mechanism


1


, the piping system can be simplified with some of pipes being eliminated for the reason of commonly used and the apparatus can be designed to a smaller size.




When the levels of the thinners stored in the ER and DR tanks


70


,


72


lowered, it is detected by the level sensor


74


and the control means


68


controls so that the fresh liquid is supplied to the tanks


71


,


72


from the fresh tank


71


based on the information from the liquid level sensor


74


and therefore there arises no difficulty in a cup cleaning. As a result, re-use of the used thinner can be also optimized.




Another embodiment of the present invention will be described.




While the first embodiment shown in

FIG. 4

is an example of a vessel which is disposed outside the ring like passage


14




a


of the drainage cup


14


and the outer side surface of the rotary cup


12


, there are various modified shapes of the vessels can conceived.




For example, it is also conceived that the exhaust path in the ring like passage


14




a


of the drainage cup is disposed under the rotary cup


12


.




In this case, as shown in

FIG. 11

, the ring like passage


14




a


is formed in such a manner that a depending wall


14




c


hanging from the ceiling section of the drainage cup


14


is connected to drainage holes


14




e


, an upper clearance


14




f


is created between the wall


14




c


and the outer side surface of the rotary cup


12


, an inner ring


17


is formed between a hill portion


14




g


and the bottom


12




b


of the rotary cup


12


to form a clearance


14




h


between the bottom


12




b


of the rotary cup


12


and the inner ring


17


, an exhaust gas guide path


14




i


is formed between the inner ring


17


and the hill portion


14




g


of the drainage cup


14


, a filter is disposed in an entrance (an opening in an upstream position) of the exhaust guide path


14




i


and air (gas) separated from the thinner is discharged through the filter


19


to the exhaust path


14




j


. In this case, thinner nozzles


15




a


,


15




b


,


15




c


and


15




d


are respectively mounted to the inner ring


17


, the hill portion


14




g


and the wall


14




c


and the thinner is jetted to the corresponding wall surfaces as objects to be cleaned. The filter


19


is, for example, a member which is constructed of corrosion resistant wires of stainless steel knitted in the state of a mesh and separates gas and liquid from the discharged material and a mist is exhausted through the exhaust path


14




i


and the thinner is descharged to the drainage holes


14




e


. Such a vessel as this is also has a film coating with a thickness of about 60 μm on the wall surfaces which is touched by the discharged liquid.




As shown in

FIG. 12

, an exhaust port


36




a


is formed in the upper portion of the outer wall of the drainage cup


14


, a ring like passage


14




a


is formed in such a manner that a wall


14




k


is inwardly protruded from a lower portion of the side wall under the exhaust port


36




a


, a wall


14




c


is vertically depending from a ceiling portion of the drainage cup


14


and the protruding wall


14




k


and the depending wall


14




c


form a detour. On the other hand, a drainage hole


14




i


which has a tapered opening having the maximum diameter at the top is formed so that an efficiency of discharging the discharged liquid can be improved. In this case, in the drainage cup, a plurality of thinner supply nozzles


15




a


,


15




b


,


15




c


and


15




e


are mounted, the thinner is jetted to the corresponding wall surfaces as objects to be cleaned. In such a vessel as constructed according to the above description, too, the wall surfaces to which the discharged liquid is touched are coated with a film of PTFE of a thickness of about 60 μm.




As shown in

FIG. 13

, an exhaust port


36




a


is formed in the upper portion of a drainage


14


, two exhaust routes are formed by dividing a ring like passage


14




a


in a detouring manner with a wall


14




b


erecting from a bottom


14




d


of the drainage cup


14


and a wall


14




c


depending from a ceiling portion of the drainage cup


14


, on the other hand, drainage holes


14




m


,


14




n


with respective tapered openings with the maximum diameters at the tops


14




m


,


14




n


are formed at the two bottoms partitioned by the wall


14




b


, and discharged liquids different in degree of contamination are discharged through different drainage holes so that the discharged liquids can be used in different uses. In this case, a plurality of thinner supply nozzles


15




a


,


15




b


,


15




c


and


15




d


are mounted in the drainage cup


14


, the thinner is jetted to respective wall surfaces which are objects to be cleaned. In such a vessel, too, wall surfaces which are touched by discharged liquid are coated by a film of PTFE having a thickness of about 60 μm.




In the above embodiment, while a thinner used for removing unnecessary resist in a peripheral portion of a glass substrate G is again used for cleaning of the insides of treatment rooms


20


of a resist coating/removing apparatuses


107


,


108


, a rotary cup


12


and a drainage cup


14


, it is needless to say that the reusage of thinner can be applied to cleaning of cups in different shapes. Besides, objects of re-use of cleaning liquid are not necessarily restricted to the cups of the resist coating/removing apparatuses


107


,


108


, but instead a cup cleaning for any of other apparatuses such as a developing apparatus or a cleaning for an object other than a cup such as a main arm or a mounting table can be included within the scope of the re-use of a cleaning liquid above mentioned.




In the first embodiment above mentioned, while the present invention is applied to A LCD substrate coating/developing system, the present invention can be also applied to a system for a treatment of an object other than a LCD substrate, such as a semiconductor wafer.




The second apparatus for a cleaning treatment according to the present invention will be described in reference to FIG.


14


.

FIG. 14

is a view showing a construction of an apparatus for coating/developing of a LCD substrate.




A different point from the apparatus for a cleaning treatment of

FIG. 10

is in that a thinner re-supply pipe


65


is connected with a fresh tank


71


with valves


64




a


,


64




c


interposed therebetween. When a used thinner A


1


is not present in an ER tank


70


, or not sufficient, An unused thinner in a fresh liquid tank is used for cleaning a rotary cu


12


and drainage cup


14


.




The third apparatus for a cleaning treatment according the present invention will be described in reference to FIG.


15


.




Different points from the apparatus for a cleaning treatment on the embodiment of

FIG. 10

are in that two ER tanks


70




a


,


70




b


are provided and an ER tank


70




c


is further provided for supplying an unused thinner A


13


to removing nozzles


51


and a rotary cup


12


.




First of all, a used thinner A


11


is recovered into the ER tank


70




a


from a mist trap


62


trough a three-way valve


64




d


. If the ER tank


70




a


is filled up, the valve


64




d


is switched and the used thinner A


12


is recovered into the ER tank


70




b


. While the used thinner A


12


is recovered into the ER tank


70




b


, a rotary cup


12


and drainage cup


14


are cleaned using the thinner A


11


in the ER tank


70




a


. If the ER tank


70




b


is filled up, the valve


64




d


is switched and, the used thinner is recovered into the ER tank


70




a


and the thinner A


12


in the ER tank


70




b


is used for cleaning. In such a manner, the two ER tanks


70




a


,


70




b


are alternately used and the used thinner can be continuously used.




Moreover, the used thinner A


13


which is supplied from the ER tanks


70




a


,


70




b


is stored in the ER tank


70




c


. The used thinner A


13


is supplied to removing nozzles


51


through a supply pipe


63




c


and a valve


64




e


and jetted to both surfaces of the outer peripheral portion of a glass substrate G. The used thinner A


13


is used for cleaning the inside of the rotary cup


12


through the supply pipe


63




c


and a valve


64




f


. A concentration of a resist in the thinner A


13


stored in the ER tank


70




c


is required to be reduced to a concentration equal to or less than a value by dilution in order to remove the unnecessary resist film in a peripheral portion of the glass substrate G or to clean the inside of the rotary cup


12


. For this reason, a concentration sensor


77


is provided in the ER tank


70




c


and if a concentration of the thinner is equal to or more than a value, then an unused thinner A


0


is supplied to the ER tank


70




c


from the fresh tank


71


for dilution.




Still another embodiment of the present invention will be described referring to an attached drawing. Here, the case where an apparatus for a cleaning treatment according to the present invention is applied to a resist coating apparatus for a LCD substrate.




The resist coating apparatus comprises, as shown in FIG.


16


: a coating mechanism


301


for applying a coating liquid, for example a resist liquid supplying it to the surface of an object to be treated in an angular shape, for example a LCD substrate G (hereinafter referred to as substrate) in the shape of a rectangle from coating liquid supply nozzles


301




a


, an edge removing mechanism


302


removing an unnecessary resist film formed by coating on a peripheral portion of the substrate G and a transport mechanism


303


transporting the substrate G coated by the coating mechanism


301


to the edge removing mechanism


302


.




A main portion of the coating mechanism


301


comprises, as shown in FIG.


16


: a spin chuck


310


which is holding means rotating the substrate G in a horizontal plane (θ direction) while vacuum holding the substrate G by a vacuum apparatus not shown, a rotary cup


312


of a cylindrical form with a ceiling and bottom with respective openings therein, which has a treatment room


320


enclosing the upper portion and the outer periphery of the spin chuck


310


; a cover


316


which can open or close an opening


312




a


of the rotary cup


312


by being mounted or demounted; a rectifying plate


317


covering the substrate G at a position thereabove, which is held by the spin chuck


310


mounted under the cover


316


; and a stationary cup


314


having a shape of a hollow ring disposed outside the rotary cup


312


in surrounding manner. Moreover, the coating apparatus


301


further comprises an apparatus for a cleaning treatment


304


which cleans the bottom surface and the inner side surface of the rotary cup


312


, the rear surface of the cover


316


, a lower surface of the outer periphery and the inner side surface of the stationary cup.




The spin chuck


310


is freely rotatable (about its axis) in a horizontal plane with the help of a rotary shaft


322


which is rotated by the drive of a drive motor


321


located at lower position, and is shiftable upward or downward by the drive of a vertical shift cylinder


323


connecting with the rotary shaft


322


. In this case, the rotary shaft


322


is slidably connected with a spline bearing


327


which is fittingly inserted in a rotary inner cylinder


326




a


which is rotatably mounted on the inner peripheral surface of a stationary collar


324


with a bearing


325




a


interposed therebetween. A driven pulley


328




a


is fixedly mounted on the spline bearing


327


, a belt


329




a


is extended between the driven pulley


328




a


and a drive pulley


321




b


fixedly mounted on a drive shaft


321




a


of the drive motor


321


. Therefore, the rotary shaft


322


is indirectly rotated by the drive of the motor


321


with the help of the belt


329




a


and then the spin chuck


310


is rotated by rotation of the rotary shaft


322


. A cylinder not shown is disposed at a lower portion of the rotary shaft


322


, the rotary shaft


322


is connected the vertical shift cylinder


323


with a vacuum seal section


330


lying therebetween in the cylinder and the rotary shaft


322


is movable by the drive of the vertical shift cylinder


323


.




The rotary cup


312


is mounted on the top of a connecting cylinder


331


fixed on a rotary outer cylinder


326




b


which is in turn mounted on the outer peripheral surface of the stationary collar


324


with a bearing


325


lying therebetween and a bearing


332


which has a sealing function is disposed between the bottom


312




b


of the rotary cup


312


and the spin chuck


310


so that the bottom


312




b


and the spin chuck


310


are rotatable relative to each other. The rotary cup


312


is rotated by rotation of the driven pulley


328




b


which is fixedly mounted on the rotary outer cylinder


326




b


, and which is rotated by a combination of the actions of the drive pulley


321




b


fixedly mounted on the drive motor


321


, the belt


329




b


which is extended between the pulleys


328




b


,


321




b


and the drive motor


321


. In this case, a diameter of the driven pulley


328




b


is set same as a diameter of another driven pulley


328




a


fixedly mounted of the rotary shaft


322


and a belt


329




a


and the belt


329




b


are engaged around the same drive motor


321


and thereby the rotary cup


312


and the spin chuck


310


are rotated at the same speed of rotation. Labylinth sealing sections (not shown) are formed in gaps between the opposed faces of the stationary collar


324


, the rotary inner cylinder


326




a


and the stationary collar


326




b


and invasion of dust into the rotary cup


312


is prevented while the apparatus is in a rotation treatment. It is also possible that the driven pulleys


328




a


,


328




b


have different diameters to achieve different speeds of rotation.




The rotary cup


312


has a structure that a tapered inner side surface, in which an inner diameter of the rotary cup


312


is decreased upwardly and that an air stream supplied from an air supply hole


334


, which is formed in the middle portion of the cover


316


which is sealed with the help of a packing


318


between the cover


316


and a opening


312




a


of the rotary cup


312


, flows on and along the rectifying plate


317


disposed under the cover


316


and further along the tapered inner surface and is discharged through an exhaust hole


335


formed at proper position on the lower outer peripheral portion, that is the outer peripheral surface of the lower part of the side wall. With provision of the air supply hole


334


and exhaust hole


335


as mentioned above, when the rotary cup


312


is rotated, an air flowing into the treatment room


320


from the air supply hole


334


is discharged through the exhaust hole


335


and thereby it is prevented that a pressure in the treatment room is reduced to a value less than a necessary negative pressure and the cover


316


can be released from the rotary cup


312


to open it without a required large force when the cover


316


is opened after completion of a cleaning treatment.




On the other band, a ring like passage


314




a


is formed in the stationary cup


314


, exhaust holes


336


connected to an exhaust apparatus not shown which holes


336


are formed at proper positions (for example at four positions along a periphery) on the outer peripheral surface and at the same time an exhaust path


337


radially disposed is formed on the upper portion of the inner periphery of the stationary cup


314


, the exhaust path


337


being communicated with the exhaust ports


336


.


9


(see FIGS.


17


and


18


). With the exhaust pots


336


on the outer periphery of the stationary cup


314


and the exhaust path


337


on the upper portion of the inner periphery of the stationary cup


314


, the exhaust path


337


communicating with the exhaust ports


336


, a mist which flows into the stationary cup


314


through the exhaust ports


336


after flying away by a centrifugal force in the treatment room


20


when a rotation treatment is carried out is prevented to flow up to the upper portion in the rotary cup


312


and discharged through the exhaust ports


336


.




The ring like path


314




a


is sectionally partitioned by an outer side wall


314




b


of the stationary cup


314


which is erected from a bottom thereof and an inner side wall


314




c


of the stationary cup


314


which is depending from a ceiling thereof in a detouring manner so that exhaust can be uniformly effected, drainage holes


314




e


are formed on a bottom


314




d


between the outer side wall


314




b


and inner side wall


314




c


at a proper distance along the peripheral surfaces of the side walls


314




b


,


314




c


. A bent portion


314




g


which is bent outwardly in the shape of a crank is provided as the lower portion of the inner side wall


314




c


, which is opposed to the lower portion of the rotary cup


312


in such a manner that a open space is formed under the bent portion


314




g


. With such a bent portion


314




g


, a stagnant air space can be created in the stream of air flowing downwardly when a resist coating treatment is conducted and thereby a resist which is sprayed away outwardly is prevented from being carried back upwardly on an air stream.




While there is a need that the cover


316


is rotated in a condition that the cover


316


is fixed to the opening


312




a


of the rotary cup


312


when the rotary cup


312


is rotated, such a condition can be produced when fixed pins (not shown) protruding from the upper surface of the rotary cup


312


and engaging holes (not shown) which are formed on the cover


316


are respectively provided and the fixed pins and engaging holes are fittingly engaged to fix the cover


316


and rotary cup


312


to each other. A robot arm not shown opens or closes the cover.




As shown in

FIGS. 17 and 18

, the apparatus for a cleaning treatment


304


comprises: a first nozzle


305


, which is inserted through a supply holes


334


formed in the middle portion of the cover


316


with a gap, and which jets (supplies) a cleaning liquid, for example a thinner B on the upper surface of the rectifying plate


317


, a second nozzle


306


mounted on a bracket


319


fixed on the rotary shaft


322


of the spin chuck


310


, which jets (supplies) a cleaning liquid, for example the thinner B on the inner side surface of the rotary cup


312


and the bottom thereof; and a third nozzle


307


, which is mounted on a horizontal stripe


314




f


extending inwardly from the bottom


314




d


of the stationary cup


314


, and which jets (supply) a cleaning liquid, for example the thinner B, toward a lower surface of the outer peripheral portion of the rotary cup


312


, the inner side surface, that is the inner side wall


314




c


, of the stationary cup


314


. The first to third cleaning nozzles


305


,


306


,


307


are connected to thinner tanks


370


,


371


and can jet a thinner independently by a gas pressure of N2 gas. The thinner tank


370


is the ER tank described in the above mentioned first to third apparatuses for a cleaning treatment and contains a recovered thinner A


1


. The thinner tank


371


contains a fresh liquid. The ER tank


370


has a concentration sensor


377


to detect a concentration in the liquid of the ER tank


370


. A resist concentration in the ER tank


370


is measured by the concentration sensor


377


and when the concentration exceeds a predetermined value a fresh liquid is supplied from the fresh liquid tank


371


to dilute the existing liquid.




With such a construction, the thinner B is jetted from the first cleaning nozzle


305


on the rectifying plate


317


and the thinner B is then sprayed away radially outwardly by a centrifugal force of the rotating rectifying plate


317


to impinge on the lower surface of the cover


316


, as shown with (


1


) of

FIG. 19

, so that a resist A attached on the lower surface of the cover


16


can be dissolved and removed.




Second cleaning nozzles


306


comprise, as shown in

FIGS. 20A

,


20


B and


20


C, the following three kinds of nozzle body: a nozzle body


306


A having a nozzle hole


306




a


which jets the thinner B toward a lower surface of the peripheral portion of the rectifying plate


317


, a nozzle body


306


B having a nozzle hole


306




b


which jets the thinner B toward the inner side surface of the rotary cup


312


and a nozzle body


306


C having a nozzle hole


306




c


which jet the thinner B toward the inner portion of the bottom of the rotary cup


312


and the second cleaning nozzles


306


are disposed at a proper angle, that is an equi-angle of 120 degree, along a periphery of the rotary cup


312


. The thinner B is jetted from the nozzle holes


306




a


,


306




b


,


306




c


of the respective nozzle bodies


306


A,


306


B,


306


C, toward a lower surface of the outer periphery of the rotating rectifying plate


317


(directions (


2


) of FIGS.


19


and


20


A), toward the inner side surface of the rotary cup


312


directions (


3


) of

FIGS. 19 and 20B

) and toward the inner portion of the bottom of the rotary cup


312


(directions (


4


) of

FIGS. 19 and 20C

) and can dissolve and remove a resist attached on respective parts of surfaces. The second nozzles


306


are only required to have at least three kinds of nozzle body


306


A,


306




b


,


306


C and a plurality of sets of the three kinds may be disposed at a proper equi-angular position along a periphery of the rotary cup


312


.




As shown in

FIGS. 21A and 21B

, third nozzles


307


comprise the following two kinds of nozzle body: a nozzle body


307


A having a nozzle hole


307




a


, which jets the thinner B toward a lower surface of the outer peripheral portion of the rotary cup


312


; and a nozzle body


307


B having a nozzle hole


307




b


, which jets the thinner B toward the inner sidewall


314




c


(in a concrete manner, the bent portion


314




g


) of the stationary cup


314


and the two kinds of nozzle body are disposed along a circular periphery of the rotary cup


312


at a proper angle, for example an equi-angle of 180 degree, about the center. The thinner B is jetted from the nozzle holes


307




a


,


307




b


of the respective nozzle bodies


307


A,


307


B toward a lower surface of the outer peripheral portion of the rotary cup


312


(direction (


5


) of

FIGS. 19 and 21A

) and toward the inner sidewall


314




f


(in a concrete manner, the bent portion


314




g


) of the stationary cup


314


and thereby a resist attached on corresponding locations can be dissolved and removed. It is only required that the third nozzles


307


comprise at least two kinds of nozzle body


307


A,


307


B and a plurality of sets of the two kinds of nozzle body


207


A,


307


B may be disposed along a periphery of the rotary cup


312


.




A main portion of the edge removing mechanism


302


comprises, as shown in FIG.


16


: a mounting able


350


which holds by suction a substrate G by a vacuum apparatus not shown, four removing nozzles


351


as first cleaning supple means, which jets a cleaning liquid, for example a resist thinner, on both surfaces of the edge potion of the four sides of the substrate G held by the mounting table


350


.




A removing nozzle


351


is mounted on a sliding member


354


which is free to slide on a guide rail


353


which is provided extending in one of X and Y directions of FIG.


16


. The sliding member


354


is constructed with a wire, a chain and a ball screw and a moving mechanism (not shown) using a stepping motor and an air cylinder and the like. A sensor which detects an adjacent position of a removing nozzle


351


is provided so that adjacent removing nozzles


351


do not collide against each other. The sensor detects one of the adjacent removing nozzles


351


approaches to the other and transmits a detecting signal to a control section not shown. The drive of the moving mechanism is stopped by a control signal from the control section and thereby interference or collision between the adjacent removing nozzles


351


is avoided.




Next a cleaning action by the apparatus for a cleaning treatment


304


will be described. A resist coating is conducted on a substrate G by the coating mechanism


301


, thereafter the cover


316


is opened, the spin chuck


310


is shifted upward and the substrate G is taken out by a transport arm not shown. Then the cover


316


is closed, the spin chuck


310


, the rotary cup


312


and the cover


316


are together rotated (for example, at a speed of rotation in the range of from 350 to 630 rpm) and at the same time the first cleaning nozzle


305


already inserted in the supply hole


334


(for air supply) with a gap jets the thinner B on the central portion of the upper surface of the rotating rectifying plate


317


. In such a situation, the thinner B jetted on the upper surface of the rectifying plate


317


is sprayed away outwardly by a centrifugal force to impinge on a lower surface of the outer peripheral potion of the cover


316


and dissolve and remove a resist A attached on the lower surface of the outer peripheral portion of the cover


316


(see FIG.


18


and (


1


) of FIG.


19


).




Then the spin chuck


310


and the rotary cup


312


are rotated at a higher speed of rotation (for example, in the range of 700 to 1300 rpm) and at the same time the thinner B is jetted from the nozzle bodies


306


A,


306


B of the second cleaning nozzles


306


toward a lower surface of the outer peripheral portion of the rectifying plate


317


and the inner side surface of the rotary cup


312


. The thinner impinges on the lower surface of the outer peripheral portion of the rectifying plate


317


and the inner side surface of the rotary cup


312


to dissolve and remove the resist A (see FIG.


18


and (


2


) and (


3


) of FIG.


19


). At the same time when cleaning of the lower surface of the outer peripheral portion of the rectifying plate


317


and the inner side surface of the rotary cup


312


, the thinner B is jetted from the nozzle bodies


307


A,


307


B of the third cleaning nozzles


307


toward a lower surface of the outer peripheral portion of the rotary cup


312


and the inner side surface, that is sidewall


314




f


(in a concrete manner, the bent portion


314




g


) of the stationary cup


314


to dissolve and remove the resist A attached on the lower surface of the outer peripheral portion of the rotary cup


312


and the inner sidewall


314




f


(in a concrete manner, the bent portion


314




g


) (see FIG.


18


and (


5


) and (


6


) of FIG.


19


).




The spin chuck


310


and the rotary cup


312


are then rotated at a lower speed of rotation (for example, in the range of 14 to 26 rpm) and at the same time the nozzle body


306


C of the second cleaning nozzle


306


jets the thinner B on the bottom surface of the rotary cup


312


. The thinner jetted on the bottom surface of the rotary cup


312


is moved on the bottom surface of the rotary cup toward the outer periphery by a centrifugal force to dissolve and remove the resist A attached on the bottom surface (see FIG.


18


and (


4


) of FIG.


19


), and further dissolve and remove the resist A attached in the exhaust hole


335


when it is discharged through the exhaust hole


335


.




In the above embodiment, while a cleaning treatment has been described in the case where the cleaning treatment is conducted in the following order: cleaning the lower surface of the outer peripheral portion of the cover


316


((


1


) of

FIG. 19

) → cleaning of the lower surface of the rectifying plate


317


, the inner side surface of the rotary cup


312


, the lower surface of the outer portion of the rotary cup


312


and the inner sidewall


314




f


(in a concrete manner, the bent portion


314




g


)(see (


2


), (


3


), (


5


), (


6


) of

FIG. 19

) → cleaning the bottom surface of the rotary cup


312


and the exhaust hole


335


(see (


4


) of FIG.


19


), the order of the steps of cleaning is not limited to the above order, but orders can be arbitrarily selected. Besides, timing of the steps of cleaning is also arbitrarily selected; for example, after each time when a resist coating on a predetermined number of substrates such as one lot of substrates is finished, a cleaning treatment can be regularly conducted.




In the above embodiments, while descriptions is limited to the cases where an apparatus and method for a cleaning treatment of the present invention is applied to a coating apparatus for a LCD substrate, the apparatus and method can be applied to a different apparatus other than the coating apparatus, for example a developing apparatus in a similar manner and to a cup cleaning in a coating apparatus, a developing apparatus and the like for an object other than a LCD substrate, for example a semiconductor wafer.




Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit of scope of the general inventive concept as defined by the appended claims and their equivalents.



Claims
  • 1. A method for a cleaning treatment, wherein a substrate coated with a coating film is put in a cup, a cleaning liquid is supplied to a peripheral portion of the substrate to dissolve a portion of the coating film with the cleaning liquid, and a dissolved substance eliminated from the edge portion of the substrate and the cleaning liquid are received by the cup, while the portion of the coating film is removed from the peripheral portion of the substrate, the method comprising the steps of:(a) draining away a part of the cleaning liquid received by the cup in an initial stage of removing the coating film, but recovering a part of the cleaning liquid received by the cup thereafter; (b) separating and removing gas from the recovered part of the cleaning liquid; (c) storing the recovered part of the cleaning liquid, from which the gas has been removed; (d) detecting a level of the stored cleaning liquid, and supplementing a fresh cleaning liquid to the stored cleaning liquid, when the detected level is lower than a predetermined level; and (e) using a mixture liquid of the supplemented fresh cleaning liquid and the stored cleaning liquid to clean at least the cup, not the substrate.
  • 2. The method according to claim 1, wherein in the step (e), the mixture liquid is also used to clean another cup.
  • 3. The method according to claim 1, wherein in the step (e), the mixture liquid is also used to clean a main arm and a mounting table.
  • 4. A method for a cleaning treatment, the method comprising the steps of:(a) forming, in a coating mechanism, a coating film on a substrate provided within a cup; (b) dissolving, in an edge cleaning mechanism, a portion of the coating film on the substrate using a cleaning liquid; (c) recovering at least a portion of used cleaning liquid from the edge cleaning mechanism; (d) separating and removing gas from the recovered part of the cleaning liquid; (e) storing the recovered part of the cleaning liquid from which the gas has been removed; (f) detecting a level of the stored cleaning liquid; (g) supplementing a fresh cleaning liquid to the stored cleaning liquid when a detected level of the stored cleaning liquid is lower than a predetermined level; and (h) using a mixture of the supplemented fresh cleaning liquid and the stored cleaning liquid to clean the cup of the coating mechanism.
  • 5. The method according to claim 4, wherein in step (h) the mixture is used to clean a main arm and a mounting table of the coating mechanism.
Priority Claims (1)
Number Date Country Kind
8-271292 Sep 1996 JP
Parent Case Info

This application is a Division of application Ser. No. 09/686,823, Filed on Oct. 12, 2000 now U.S. Pat. No. 6,398,879; which is a divisional of Ser. No. 08/935,917 filed on Aug. 23, 1997 now U.S. Pat. No. 6,159,288, all of which are hereby incorporated by reference in their entirety.

US Referenced Citations (24)
Number Name Date Kind
4788994 Shinbara Dec 1988 A
4838979 Nishida et al. Jun 1989 A
4871417 Nishizawa et al. Oct 1989 A
4894260 Kumasaka et al. Jan 1990 A
4903717 Sumnitsch Feb 1990 A
5041165 Urbani Aug 1991 A
5120370 Mori et al. Jun 1992 A
5235995 Bergman et al. Aug 1993 A
5312487 Akimoto et al. May 1994 A
5383483 Shibano Jan 1995 A
5431178 Chiu Jul 1995 A
5488964 Murakami et al. Feb 1996 A
5518542 Matsukawa et al. May 1996 A
5538024 Inada et al. Jul 1996 A
5540244 Brooks Jul 1996 A
5591262 Sago et al. Jan 1997 A
5608943 Konishi et al. Mar 1997 A
5677000 Yoshioka et al. Oct 1997 A
5688322 Motoda et al. Nov 1997 A
5762708 Motoda et al. Jun 1998 A
5776250 Shin et al. Jul 1998 A
5778911 Yoshio Jul 1998 A
5779796 Tomoeda et al. Jul 1998 A
5979474 Manako Nov 1999 A
Foreign Referenced Citations (5)
Number Date Country
2-216633 Aug 1990 JP
7-115060 May 1995 JP
7-130694 May 1995 JP
8-88168 Apr 1996 JP
9-1035 Jan 1997 JP