Patent Application
20110192420
This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2010-24261, filed on Feb. 5, 2010, the entire contents of which are incorporated herein by reference.
Exemplary embodiments described herein generally relate to a cleaning apparatus and a method of fabricating a semiconductor device using the cleaning apparatus.
Conventionally, scrub cleaning has been performed as a method for cleaning a substrate surface of a semiconductor substrate, a display substrate or the like. In a scrub cleaning process, a member constituted with a sponge brush or the like is scrubbed to the substrate surface, providing pure water or the like.
For example, a roll cleaning apparatus or a scrub cleaning apparatus is used as the cleaning apparatus in which a roll-type sponge as the cleaning member is scrubbed on the surface of the semiconductor substrate or the like.
In the scrub cleaning process, the cleaning member is directly contacted on the semiconductor substrate or the like to clean the semiconductor substrate or the like. Therefore, when a contamination object is included in the cleaning member itself, the cleaning member acts as a contamination source, so that decreasing cleaning effect on the semiconductor substrate or the like is caused.
The contaminated cleaning member is exchanged with new one for maintaining cleaning effect as one approach. However, it is necessary that the cleaning apparatus is worked out and a new cleaning member is provided in exchanging the cleaning member, so that running cost is increased. Accordingly, the contaminated cleaning member is scrubbed to a quartz substrate or the like to remove the contamination, for example.
Further, a cleaning solution in which resin particles are dispersed is used in the scrub cleaning process. In such a manner, a method as a process after CMP (Chemical Mechanical Polishing) is disclosed. In the method, a solid contamination such as a polishing particle, a polishing product or the like adhered on the surface of the semiconductor substrate or the like is removed.
However, using the cleaning solution including the dispersed resin particles in the disclosed method may force the resin particles to be the contamination object for the cleaning member.
A problem is generated that the method of removing by scrubbing the contaminated cleaning member with the solid contamination to the quartz substrate or the like is insufficient for sustaining a cleaned state of the cleaning member.
In one embodiment, a cleaning apparatus, including, supporting bodies supporting and rotating a substrate, a first cleaning member and a second cleaning member, each of the cleaning member having a circular shape and rotating around a rotational symmetry axis, periphery portions of the first cleaning member and the second cleaning member being able to contact to opposed surfaces of the substrate to be processed each other, the substrate being supported by the supporting bodies, a first brush-cleaning member and a second brush-cleaning member, each of the brush-cleaning members having a groove with a V-shape cross section being widened upwards, a brush with a cleaning function being formed on a slope plane of the groove, the first cleaning member and the second cleaning member being able to shift to contact to the slope planes of the grooves in the first brush-cleaning member and the second brush-cleaning member, respectively, first cleaning solution supply portions supplying a first cleaning solution dispersed resin particles to the surfaces to be processed, and second cleaning solution supply portions supplying a second cleaning solution to peripheries of the first cleaning member and the second cleaning member which are arranged to contact to the slope planes of the first brush-cleaning portion and the second brush-cleaning portion, respectively.
In another embodiment, a method of fabricating a semiconductor device, including, forming a film to be processed on a semiconductor substrate, polishing the film to be processed, contacting both a surface on which the film is formed and a back surface opposed each other of the semiconductor substrate to periphery portions of the first cleaning member and the second cleaning member, respectively, supplying a first cleaning solution dispersed the resin particles to clean the semiconductor substrate, shifting the contacting portions, shifting the first cleaning member and the second cleaning member to positions of a first brush-cleaning member and a second brush-cleaning member, respectively, each of the brush-cleaning members setting to be apart from the semiconductor substrate and having a groove with a V-shaped cross section being widened upwards, a slope plane on the groove being a cleaning surface with a brush, contacting periphery portions of the first cleaning member and the second cleaning member to the clean surface of the brush-cleaning members, and supplying a second cleaning solution to clean the first cleaning member and the second cleaning member, shifting the contacting portions.
A Embodiment will be described below in detail with reference to the attached drawings mentioned above. Throughout the attached drawings, similar or same reference numerals show similar, equivalent or same components.
A cleaning apparatus and a method of cleaning a cleaning member according to an embodiment is described in detail with reference to
As shown in
In a fabricating process, for example, a cassette (not shown) is set in the carrier gateway 110. The semiconductor substrates 11 in one lot which is constituted with twenty-five substrates, for example, are installed. Each semiconductor substrate 11 in the cassette is carried into the polishing apparatus 130 by the carrier system 120. A surface and a back surface of the semiconductor substrate are polished on the polishing table 131, for example, by CMP. After polishing in the polishing apparatus 130, the semiconductor substrate 11 is carried out from the polishing apparatus 130 and carried into the cleaning apparatus 1 by the carrier system 120. Scrub cleaning is performed on the surface and the back surface of the semiconductor substrate in the cleaning apparatus 1 by using the roll member 21 (shown in
After finishing scrub cleaning in the cleaning apparatus 1, the semiconductor substrate 11 is carried out from the cleaning apparatus 1 and carried into the pencil-cleaning and the spin-drying apparatus 140 by the carrier system 120. Pencil-brush-cleaning is performed on the surface of the semiconductor substrate 11 in the pencil-cleaning and spin-drying apparatus 140. Subsequently, the semiconductor substrate 11 is rotated with high speed to splash water by centrifugal force, so that the semiconductor substrate 11 is spin-dried. The semiconductor substrate 11 spin-dried is carried out and into the carrier gateway 110 by the carrier system 120 to be returned in the original cassette.
As shown in
The semiconductor substrate 11 is not restricted to a semiconductor wafer but includes a substrate in which a necessary structure is formed on the surface of the semiconductor device. Further, the semiconductor substrate 11 is not restricted to silicon as a main portion but includes a compound semiconductor, an oxide substrate or the like having a semiconductor film which is grown on a surface thereof. The semiconductor substrate 11 can be replaced with various kinds of substrates, a glass substrate, for example, a substrate of a liquid crystal display, an organic EL (Electroluminescence) display, a plasma display or the like, a substrate for a photo disc such, for example, a resin substrate, a substrate for magnetic disc, for example, an aluminum substrate, a photo-mask substrate, for example, a glass substrate or the like.
The rotation supporters 13 support the periphery portion of the semiconductor substrate 11 which is nearly a circular shape. The rotation supporters 13 can be rotated in a horizontal plane. The rotation supporters 13 are located at positions without contacting with the roll member 21. The six positions, for example, are arranged by nearly equal interval, however, are not restricted to the number and the positions.
The roll member 21 has nearly a cylindrical shape with a curved side surface and both bottom surfaces with a circular shape. The roll members 21 are located upward and downward to the semiconductor substrate 11 and the side surfaces of the roll members 21 is set to be in parallel to the surface and the back surface opposed each other of the semiconductor substrate 11, respectively. The roll member 21 covers a diameter of the semiconductor substrate 11. Each roll member 21 is supported with a roll member supporter 25. The roll member 21 shifts along the vertical line of the roll member supporter 25 so as to close and separate with the semiconductor substrate 11, so that the roll member 21 can change a position to a state contacting or no contacting to the semiconductor substrate 11. The roll member supporter 25 can control pressure by which the roll member 21 presses the semiconductor substrate 11 along the vertical line. The roll member supporter 25 provides rotational driving force to the roll member 21 by setting the center of the both bottom surface of the roll member 21 as an axis which is the isotropic rotation axis of the cylinder shape.
One of the brush-cleaning members 27 is arranged at an opposite side position of the semiconductor substrate 11 to the rotation supporters 13 (called an outer side, hereinafter) and the other is arranged at a lower position apart from the semiconductor substrate 11 (called a lower side, hereinafter). The roll member supporter 25 enable the roll member 21 at the outer side to cross over the rotation supporter 13 so as to shift to the position of brush-cleaning member 27 at the outer side and to shift the roll member 21 at the lower side to the position of the brush-cleaning member 27 at the lower side.
The scrub cleaning solution supply portions 15 are arranged obliquely upward and downward for avoiding immediately above and below the semiconductor substrate 11 to supply the scrub cleaning solution 17 in which the resin particles 18 are dispersed to an upper and a lower contacting portions between each of the surfaces of the semiconductor substrates 11 and each of the roll members 21, respectively. Each of the scrub cleaning solution supply portions 15, for example, includes an injection portion with a nozzle type to be able to supply the scrub cleaning solution 17 apart from the scrub cleaning solution supply portion 15. The plurality of the scrub cleaning solution supply portions 15 can be arranged at both upper and lower sides along the contacting portion between the surface of the semiconductor substrate 11 and the roll member 21.
Pure water is used as the scrub cleaning solution 17, for example, however, ion-exchange water through ion-exchange resin can be used. Further, a solution containing a component which proceeds to clean a contaminant can be used.
A material, for example, polymethylmethacrylate (PMMA), polystyrene (PS), polyethylene (PE), polyethyleneglycol, polyvinyl acetate, polybutadiene, polyisobutylene, polypropylene, polyoxymethylene or the like can be selected as the resin particle 18. The resin particle 18 can be constituted with single material or mixed materials more than two kinds. As mentioned later, a primary particle diameter of the resin particle 18 is selected in a range of 10 to 60 nm.
As shown in
As shown in
The brush-cleaning member 27 includes a base portion 28 in which a V-shaped groove opened upward is formed. The brush portion 29 is formed on the slope plane constituting the groove of the base portion 28. Fine bristles are formed on the brush portion 29. The bristles are constituted with resin which is harder than the sponge portion 23. The leading edge of each bristle is rounded and the bristles are perpendicularly distributed on the slope plane of the base portion 28. The fine bristle in this embodiment indicates to have a larger length than the diameter from the surface. On the other hand, the fine bristle is not necessary but the diameter can be relatively larger than the length, namely, convex and concave is distributed in the surface of the brush portion 29. The length of the brush portion 29 is desirable to be just long enough to over the height of the convex and concave in the sponge portion 23. Further, the slope plane constituting the groove of the base portion 28 is not necessary to be formed in integrated fashion at the bottom of the groove, but isolated slope planes can be located at intervals.
A through hole which can pass to the bottom surface side is opened at the bottom portion of the V-shaped groove in the brush-cleaning member 27 to enable the pure water 35 or the like to flow out. The bottom portion is the lowest position of the base portion 28. The pure water 35 supplied from an upper portion runs the surface of the brush-cleaning member 27 or the like to fall down to the through hole by one way. Further, when the V-shaped groove has a slope which is lowered towards outside of the brush-cleaning member 27, the through hole is not necessary.
The brush-cleaning member 27 can contact with the roll member 21 at the two surfaces of V-shaped groove. Further, the brush-cleaning member 27 is connected to an ultrasonic generator 31 to enable the brush portion 29 to vibrate in a state contacting with the roll member 21. A length of the brush-cleaning member 27 is longer than the length along the rotation axis of the roll member 21. The length of the brush-cleaning member 27 is desirable to be at least longer than a portion of the roll member 21 which contacts with the semiconductor substrate 11. Further, the brush-cleaning member 27 can be provided vibration with smaller frequency than ultrasonic wave. The brush-cleaning member 27 can be rolled to scrub an external periphery portion of the roll member 21.
Next, a method for cleaning the roll member 21 of the cleaning apparatus 1 is described. As shown in
The roll member 21 at the upper side is carried at a position of the brush-cleaning member 27 at the outer side, for example, sifting upward from the surface of the semiconductor substrate 11, outside and downward as shown by the broken arrows to be arranged at the brush portion 29 of the groove of the brush-cleaning member 27. Accordingly, the roll member 21 contacts with each of the two portions of the brush portion 29. The roll member 21 at the lower side is arranged at a position of the brush-cleaning member 27 at the lower side, for example, sifting downward from the semiconductor substrate 11 as shown by the dotted arrows. Accordingly, the roll member 21 is located on the brush portion 29 of the groove of the brush-cleaning member 27 to contact with the two portions of the brush portion 29. The semiconductor substrate 11 after cleaning is shifted by the carrier system 120.
The roll member 21 is rotated by a driving force from the roll member supporter 25 in a state that the roll member 21 is contacted with the brush-cleaning member 27 at the two portion, in other word, in a state that the roll member 21 is pressed to the brush-cleaning member 27. The pure water 35 is supplied from the pure water supply portion 33 to clean the roll member 21. Vibration by the ultrasonic generator 31 is added on the brush-cleaning member 27. The pure water 35, a solid contamination included in the pure water 35 and the resin particle 18 are flowed in one way to be discharged from the through hole formed in the bottom portion of the V-shaped groove of the brush-cleaning member.
After finishing to clean the roll member 21 by the brush-cleaning member 27, ultrasonic wave, rotation, press, pure water 35 or the like is stopped, and the roll member 21 is returned along the reverse direction of the broken and dotted arrows. Before the roll members 21 interleaves from one above the other, the semiconductor substrate 11 is carried into the position by the carrier system 120 and is set on the rotation supporter 13. After that, next semiconductor substrate 11 is repeatedly carried into the position via cleaning the semiconductor substrate 11, carrying out the semiconductor substrate 11 and cleaning the roll member 21. After cleaning the final semiconductor substrate 11, it is desirable to perform cleaning the roll member 21.
Next, an example which the cleaning apparatus 1 is applied to a fabricating process of a semiconductor device is described. Effects are evaluated by comparison with a fabricating process of a comparative example.
As shown in
Plugs 53 constituted with tungsten (W) are embedded in the insulator 52. The laminated insulator is constituted with the first insulator 54 with relative permittivity of less than 2.5 and the second insulator 55 formed on the first insulator with relative permittivity being larger than that of first insulator 54. Thicknesses of both the first insulator 54 and the second insulator 55 are set to be 100 nm.
The first insulator 54 can be formed using at least one selected from groups of a film having siloxane skeleton such as polysiloxane, hydrogen silsesquioxane, polymethylsiloxane, methysilsesquioxane or the like, a film having organic resin as a main component such as polyarylether, polybenzoxazole, polybenzocyclobutene or the like, and a porous film such as porous silica film or the like. The first insulator 54 constituted with such a material is brittle.
The second insulator 55 acts as a cap insulator, and can be formed by using, for example, an insulator at least one selected from a group, having relative permittivity more than 2.5, of SiC, SiCH, SiCN, SiOC, SiN, and SiOCH. A surface of the second insulator 55 constituted with such a material has hydrophobicity. Further, an insulator such as SiO, SiOP, SiOF, SiON or the like, which has hydrophilicity, may be adhered as a residue in the surface after finishing CMP. The scrub cleaning solution 17 with dispersed resin particles 18 can be suited to such an insulator in this embodiment.
After a wiring groove is formed in the laminated insulator mentioned above, the barrier metal film 56 and the wiring material film 57 are wholly deposited. The barrier metal film 56 with a film thickness of 10 nm can be formed by using Ta, and the wiring material film 57 with a film thickness of 400 nm can be formed by using Cu.
As shown in
Next, an unnecessary portion of the barrier metal film 56 and the wiring material film 57 is removed by CMP as shown in
(First Polishing Step)
Slurry: CMS7401/7452 (JSR Co., Ltd.)
Flow Rate: 300cm3/min;
Polishing Pad: IC1000 (NITTA HAAS Inc.);
Load: 300 gf/cm2 (2.9E4Pa);
A number of rotations of both a carrier fixing the semiconductor substrate 11 (not shown) and a polishing table 131 are set to be 100 rpm, and the sample is polished for one minute.
(Second Polishing Process)
Slurry: CMS8401/8452 (JSR Co., Ltd.)
Flow Rate: 200 cm3/min;
Polishing Pad: IC1000 (NITTA HAAS Inc.);
Load: 300 gf/cm2 (2.9E4Pa);
A number of rotations of both the carrier fixing the semiconductor substrate 11 (not shown) and the polishing table 131 are set to be 100 rpm, and the sample is polished for thirty seconds.
After immediately finishing the second polishing step as shown in
As shown in
Here, an experiment is performed mentioned below for investigating an optimum range of a primary particle diameter of the resin particle. Particles, each having a deferent primary particle diameter, constituted with PMMA are prepared as the resin particle. The primary particle diameter of the resin particle can be measured by using a photograph, for example, obtained from SEM (Scanning Electron Microscope) or TEM (Transmission Electron Microscope). Removing the adhered materials is carried out by using each resin particle with a primary particle diameter being 5 nm-100 nm.
Specifically, using each scrub cleaning solution dispersed with the resin particle, the surface at each step as shown in
Conditions in the cleaning process are mentioned below. Scrub cleaning solution flow rate is 300 cm3/min, and a number of both the semiconductor substrate 11 and the roll member 21 is 100 rpm. As shown in
Further, as shown in
The result processed by the cleaning apparatus 1 in this embodiment indicates, as black circles, the defect number is zero over the twenty-five substrates per lot. On the other hand, the result, in which the scrub cleaning solution 17 is used in the cleaning apparatus similar to the cleaning apparatus 1 and the brush-cleaning member 27 is replaced with the plane quartz substrate, indicates that the defect number continues to be zero halfway in one lot, subsequently, the defect number is gradually increase in just enough to twenty as shown by triangles.
The results in which the scrub cleaning solution without dispersing the resin particle 18 is used in the cleaning apparatus similar to the cleaning apparatus 1 is indicated by square marks or cross marks. The defect number fluctuates between thirty-five and eighty-five without almost relationship to the brush-cleaning member 27 and the plane quartz substrate. These result reveals that the resin particle 18 is greatly contributed to clean the semiconductor substrate 11 and cleaning effect can be maintained by using the brush-cleaning member 27. Reversely, the method of scrubbing the roll member 21 on the quartz substrate is indicated to be insufficient under the condition of cleaning by the brush-cleaning member 27. As the solid contaminations and the resin particles are accumulated in the roll member 21, the method of scrubbing of the roll member 21 on the quartz substrate is, for example, necessary for cleaning in longer time.
The brush portion 29 is formed on the surface contacted to the roll member 21 in the brush-cleaning member 27 and can be constantly contact to the roll member 21 on the two portions. The brush-cleaning member 27 can quickly clean the roll member 21 as compared to the quartz substrate by having convex and concave with further difference in height, a number of contacting portions, the pure water 35 including adhered solid materials flowing one way or the like, or combination with theirs.
As mentioned above, the cleaning apparatus 1 uses the scrub cleaning solution 17 with the dispersed resin particles 18 which has the primary particle diameter from 10 nm to 60 nm and the roll member 21 so as to clean the surface of the semiconductor substrate 11. Further, the cleaning apparatus 1 cleans the surface of the roll member 21 using the brush-cleaning member 27 having brush portion 29 on the surface of the V-shaped groove and the pure water 35 between cleaning processes of the surface of the semiconductor substrate 11.
The cleaning apparatus 1 can constantly clean the solid contaminations including the resin particles 18 adhered to the roll member 21. As the surface of the semiconductor substrate 11 is cleaned by the cleaned roll member 21, the surface of the semiconductor substrate 11 carried in orders can be continually cleaned. In other word, the roll member 21 is controlled to prevent accumulation of the solid contaminations. As the defects on the surface are decreased, a yield of the semiconductor devices in the process can be controlled to avoid deterioration. Further, a usable period of the roll member 21 till exchanging the roll member 21 can be extended. Accordingly, the cleaning apparatus 1 can be suppressed on a fabricating cost of the semiconductor device.
In the embodiment, the brush-cleaning member having the V-shaped slope plane in which the two planes are set to be an angle of nearly ninety degree is described, for example. However, when a roll member can be contacted to two planes and can be sift in and out to an upper and lower direction of the V-shaped groove, the two planes formed as the V-shaped plane can be suited larger or smaller than ninety degrees. Both of the two planes formed as the V-shaped plane are formed as a plane, for example. On the other hand, a curved surface can be used.
While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the inventions. Indeed, the novel embodiment described herein may be embodied in a variety of other forms; furthermore, various omissions, substitutions and changes in the form of the embodiments described herein may be made without departing from the spirit of the inventions. The accompanying claims and their equivalents are intended to cover such forms or modifications as would fall within the scope and spirit of the inventions.
| Number | Date | Country | Kind |
|---|---|---|---|
| P2010-024261 | Feb 2010 | JP | national |
