CSP plate holder

Information

  • Patent Grant
  • 6386191
  • Patent Number
    6,386,191
  • Date Filed
    Thursday, August 31, 2000
    24 years ago
  • Date Issued
    Tuesday, May 14, 2002
    23 years ago
Abstract
Disclosed is a CSP plate holder for use in dicing a CSP plate into individual pellets and in transporting and putting them in a transport tray. The CSP plate holder is composed of a flat plate for sucking and fixedly holding a CSP plate thereon. The flat plate has pellet areas each allotted to each of the individual pellets. Each pellet area has a through hole for sucking and fixedly holding the pellet while the CSP plate is being diced. Each pellet area has at least one suction hole for sucking and fixedly holding the pellet while the CSP plate is being transported. The flat plate has duct passages permitting the suction holes to communicate with a suction source for applying a suction force to the pellet. In addition, the flat plate has at least one minute through hole made in each pellet area.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a system for dicing a CSP plate into pellets and for transporting and putting them into a transport tray, and more particularly a CSP plate holder to be used therein.




2. Related Arts




Referring to

FIG. 15

, a CSP (abbreviated for “Chip Size Package”) plate


200


is composed of a plurality of semiconductor chips hermetically sealed and packaged with glass or epoxy resin as a whole. The CSP plate chip can be cut crosswise along the crossing lines


201


and


202


into individual CSPs of same size as a semiconductor. These CSPs are transferred to a transport tray for shipping, or they are transported to an assembling line in the factory to be built in printed circuit boards. Thus, small-sized electronic devices such as notebook-sized personal computers, cellular phones and such like can be provided.




A CSP plate


200


can be diced crosswise to individual pellets by using a dicing machine. Referring to

FIG. 16

, each CSP plate


200


is fixedly held to a frame F with the aid of adhesive tape T, and the CSP plate thus held can be diced as it is.




A plurality of CSP plate-and-frame combinations are laid on each other to form a stack, and the stack is put in a cassette. After the CSP plate has been diced, the diced CSP plate is still held on the frame, and the diced CSP plate-and-frame combination is put in the cassette. All CSP plates are cut into individual pellets, and then they are transported to the pick-up station where pellets are picked up from a selected diced CSP plate for transferring and putting one by one in a selected transport tray. The transport tray thus loaded with pellets are shipped or brought to an assembling line in the factory.




Apart from the dicing work, it is necessary that CSP plates


200


are fixedly held to frames F with the aid of adhesive tapes T. Before completing this, the dicing work cannot start, and accordingly the productivity is lowered. Also, extra apparatus need to be provided for applying tapes T both to frames F and CSP plates


200


, and installation of such extra apparatus is disadvantageous from the economical point of view.




After picking up pellets from diced CSP plate-and-frame combinations, it is necessary that: used adhesive tapes T are peeled off from the frames F; new adhesive tapes T are applied to the frames F; and finally new CSP plates


200


are put on the tapes T. Specifically used frames F are collected to peel their adhesive tapes off, and new adhesive tapes are applied both to the frames F and the CSP plates


200


. This work must be begun after finishing the pick-up work, and must be finished before resuming the dicing work. This is a cause for preventing the productivity from being improved. In addition, lots of used adhesive tape must be thrown away, causing a significant pollution in the surrounding.




SUMMARY OF THE INVENTION




What is aimed at by the present invention is to dice a CSP plate into pellets at an increased efficiency without causing any pollution in the surrounding.




To attain this object according to the present invention, a CSP plate holder for use in dicing a CSP plate into individual pellets and in transporting and putting them in a transport tray comprises: a flat plate for bearing a CSP plate thereon, said flat plate having a plurality of pellet areas each allotted to each of the individual pellets, each pellet area having a through hole made therein for sucking and fixedly holding the pellet, said flat plate having engagement means for holding said CSP plate while being transported.




The CSP plate holder can be used repeatedly, not producing any disposables which may cause pollution in the surrounding. Collection of used tapes and application of new tapes both to CSP plates and associated frames are not required, and accordingly the productivity can be improved.




The engagement means may comprise at least one suction hole made adjacent to the through hole in each pellet area for sucking and fixedly holding the pellet while the CSP plate is transported, and duct passages permitting the suction hole to communicate with a suction source for applying negative pressure to the pellet.




With this arrangement the CSP plate can be fixedly held by applying negative pressure to the CSP plate via the through holes while being diced, and by applying negative pressure to the diced CSP plate via the suction holes while being transported.




The flat plate may have at least one minute through hole made in each pellet area, thereby permitting the minute through hole to be selectively used in picking up the pellet for transporting to the transport tray. With this arrangement the pick up of each pellet is facilitated.




The CSP plate holder may comprise further an elastomeric sheet laid on said flat plate. Use of such an elastomeric sheet assures that a CSP plate be held in stable condition even though the CSP plate is somewhat bent. The elastomeric sheet may be of a synthetic resin.




The elastomeric sheet may be applied to the flat plate by an adhesive agent, which is sensitive to ultraviolet rays for reducing its adhesive power. Thus, removal of the elastomeric sheet is facilitated.




Other objects and advantages of the present invention will be understood from a CSP plate holder and a table for bearing the same according to preferred embodiments of the present invention, which are shown in accompanying drawings.











BRIEF DESCRIPTION OF THE DRAWING





FIG. 1

is a perspective view of a dicing machine in which CSP plate holders according to the present invention are used;





FIG. 2

illustrates one example of CSP plate and an associated CSP plate holder according to a first embodiment of the present invention;





FIG. 3

illustrates another example of CSP plate and an associated CSP plate holder according to the first embodiment of the present invention;





FIG. 4

is a sectional view of the CSP plate holder taken along the line


4





4


in

FIG. 2

;





FIGS. 5A

to


5


D illustrate how a selected CSP plate holder can be taken out from the rack;





FIG. 6

is a block diagram of a decision making system which can make a decision as to whether or not a selected CSP plate holder is appropriate for holding a selected type of CSP plate;





FIGS. 7A

,


7


B and


7


C show contents of the first, second and third memory means of the decision making system;





FIG. 8

is a perspective view of a CSP plate-and-CSP plate holder combination;





FIG. 9

is a perspective view of a CSP plate holder according to a second embodiment of the present invention;





FIG. 10

is a sectional view of the CSP plate holder taken along the line


10


-


10


in

FIG. 9

;





FIG. 11

illustrates a CSP plate holder according to a second embodiment of the present invention, and an associated elastomeric sheet;





FIG. 12

illustrates a CSP plate holder having an elastomeric sheet laid thereon;





FIG. 13

illustrates a CSP plate holder having an elastomeric sheet and a CSP plate laid thereon;





FIG. 14

is a perspective view of a table for bearing a CSP plate holder according to the second embodiment;





FIG. 15

is a perspective view of a CSP plate; and





FIG. 16

illustrates a CSP plate-and-frame combination.











DETAILED DESCRIPTION OF PREFERRED EMBODIMENT




CSP plate holders according to the present invention are described as being used in a dicing machine


10


as shown in FIG.


1


. In the dicing machine


10


, each CSP plate is diced into individual CSPs, which are transported to and put in a transport tray. CSP plates


11


are laid on each other to form a stack. The stack of CSP plates are put in the cassette


13


, which is put on the cassette bearing table


12


. It can be raised or lowered.




The holder rack


15


contains a plurality of different types of CSP plate holders, each of which can support an overlying CSP plate while being diced. Two or more different types of CSP plate holders are prepared to meet different types of CSP plates; these CSP plates are different in size and thickness, and have different numbers of pellets arranged in lattice. The CSP plate holders, therefore, must have different lattices of “let-in” grooves in conformity with the different crosswise arrangements of pellets of different type CSP plates. Such “let-in” grooves allow the cutting blade to enter when cutting the CSP plate into pellets. In

FIG. 1

four pieces each of the four types of CSP plate holders


100




a


,


100




b


,


100




c


and


100




d


are put in different shelves given addresses of Nos.


1


,


2


,


3


and


4


in the holder rack


15


.




Referring to

FIG. 2

, the. CSP plate


11


is a flat plate having crosswise cutting lines


16


and


17


to separate into CSPs or pellets. The CSP plateholder


100




a


is so made that the CSP plate


11


may be fixedly held on its rear side, and that each and every CSP may be fixedly held after the CSP plate


11


is diced. Specifically, the CSP plate holder


100




a


has a plurality of sections defined by its crosswise grooves


101


and


102


, corresponding to the crosswise cutting lines


16


and


17


of the overlying CSP plate


11


, and each section has a single through hole


103


(3 to 5 millimeters in diameter) and two suction holes


104


of less diameter. These apertured sections make up together a CSP plate bearing area.




Referring to

FIG. 3

, a CSP plate


22


has an increased number of crosswise cutting lines


23


and


24


, and accordingly an increased number of sections defined thereby. As a matter of course, a CSP plate holder


100




b


to be combined with such a CSP plate


22


has a corresponding increased number of crosswise grooves


111


and


112


, accordingly an increased number of sections defined thereby. The numbers of the through holes


113


and suction holes


114


are increased accordingly.




Referring to

FIG. 2

again, the CSP plate holder


100




a


has three engagement holes


105




a


,


105




b


and


105




c


made on its longitudinal sides. The suction pipes


64


,


73


and


79


of the first, second and third transport means


60


,


69


and


74


can be inserted in these engagement holes


105




a


,


105




b


and


105




c


respectively. Referring to

FIG. 4

, the through holes


103


pass through the thickness of the plate


100




a


from the front to rear side whereas the suction holes


104


for the plate sucking-and-transporting use communicate with the three engagement holes


105




a


,


105




b


and


105




c


via the duct passages


106


, which are made in the thickness of the plate


10




a.






Each CSP plate holder has an identification mark


107


formed on its front. For example, the identification mark


107


is given in the form of the particular number of through holes. In

FIG. 2

the CSP plate holder


100




a


has three through holes


108


made therein. In

FIG. 3

the CSP plate holder


100




b


has two through holes


108


made therein. Bar codes may be used as an identification mark.




Referring to

FIGS. 5A

to


5


D, the CSP plate holder putting in-and-taking out unit


35


comprises an upright wall


37


having an “L”-shaped stage


39


vertically movable thereon, and a CSP plate holder putting in-and-taking out table


36


horizontally movable on the cantilever-like extension of the “L”-shaped stage


39


. The upright wall


37


has a vertical slot


40


and two parallel vertical rails


38


laid on the opposite sides of the vertical slot


40


. The “L”-shaped stage


39


has a rear projection formed on its dependent extension. The rear projection has a tapped hole made thereon, and the rear projection is slidably fitted in the vertical slot of the upright wall


37


. The upright wall


37


has a motor drive


41


placed at its top, and a screw rod is integrally connected to the shaft of the motor drive


41


, extending downward on the rear side of the upright wall


37


to be threadedly engaged with the tapped hole of the rear projection of the “L”-shaped stage


39


. Thus, clockwise or counter clockwise rotation of the shaft of the motor drive


41


will raise or lower the “L”-shaped stage


39


on the upright wall


37


.




A CSP plate holder putting in-and-taking out table


36


rides on two parallel rails


42


, which are laid on the cantilever-like extension of the “L”-shaped stage


39


. As shown, the cantilever-like extension has a drive


36


a attached to one corner for driving the table


36


back and forth within a certain limited range in the ±Y-axial direction on the cantilever-like extension of the “L”-shaped stage


39


. Also, the table


36


has detecting means


46


for detecting the identification mark


107


, which is formed in the CSP plate holder. In this particular embodiment, the detecting means


46


comprises four photo-generative and photo-receptive semiconductor elements


43


. These photo-sensors can be used in making a decision as to whether a CSP plate holder to be taken out is appropriate for use in holding a selected CSP plate to be diced.




In taking out an appropriate CSP plate holder


100




a


from the rack


15


, the “L”-shaped stage


39


is raised or lowered until it has come to a level given the address searched and found beforehand, and then, the stage


39


is lowered somewhat below the level. Then, the table


36


is moved in the +Y-axial direction to be laid under the CSP plate holder


100




a


in the rack


15


(see FIG.


5


B), and a decision is made as to whether the overlying holder is appropriate for holding the selected CSP plate to be diced.




Referring to

FIG. 6

, the decision-making unit


44


comprises a data input means (console)


50


for inputting pieces of information, a control means (CPU)


45


, and first, second and third memory means


47


,


48


and


49


.




The control means


45


permits the storing of selected pieces of information from the data input means


50


in one of these memory means, and the retrieving from the memory means, and the control means makes a required comparison between pieces of information retrieved from different memory means and a required decision on the basis of such comparison.




The detecting means


46


is composed of the photo-sensors


43


in the CSP plate holder putting in-and-taking out table


36


(see

FIG. 5

) if the identification mark


107


is given in the form of holes, and is composed of a barcode reader if the identification mark


107


is given in the form of barcode.




Specifically, an operator stores the identification number of CSP plates


11


to be diced in the first memory means


47


by using the data input means


50


. The identification number is a three-digit number varying with the size and thickness of the plate, the size of pellets and such like. In this particular example the identification number is


001


, and is stored in the first memory means


47


, indicating that a selected CSP plate whose identification number is


001


is to be diced, as seen from FIG.


7


A.




As seen from

FIG. 7B

, the second memory


48


stores identification numbers of different types of CSP plates, identification letters of associated jig holders and the number of identification holes; addresses of jig holders in the rack; pellet sizes and such like, as for instance follows: the identification letter of the type of jig holder to be associated with a CSP plate whose identification number is


002


is B; such type of jig holders are stored at the addresses


2


-


1


,


2


-


2


,


2


-


3


and


2


-


4


in the rack


15


; the pellet size of the


002


CSP plate is 5 millimeter square, and the CSP plate can be divided into 6 (longitudinal divisions) times 14 (lateral divisions).




The detecting means


46


detects the identification holes


107


of the CSP plate holder which is about to be taken out by the putting in-and-taking out table


36


. The number of the identification holes along with the identification letter are stored in the third memory means


49


, as seen from FIG.


7


C.




The data input means


50


in the form of console


51


is positioned on the front side of the dicing machine


10


, and it is used in putting pieces of information in the first and second memory means


47


and


48


.




First, the operator inputs in the first memory means


47


the identification number


001


of a selected CSP plate


11


to be diced.




After finding which address in the rack a required CSP plate holder is located by referring to the content of the second memory, the putting in-and-taking out table


36


is moved to the address thus found, and then the putting in-and-taking out table


36


is made to advance under the CSP plate holder


100




a


(identification letter A) in the rack


15


, as seen from FIG.


5


B. The identification holes of the CSP plate holder


100




a


are detected by the detector


46


, and the number of the so detected identification holes is stored in the third memory


49


.




Specifically the photogenerative semiconductor elements


43


project beams of light to the holes


108


of the overlying holder


100




a


. The beam of light directed to the hole-less area is reflected from the rear side of the holder


100




a


whereas the other beams of light directed to the holes


108


are not reflected from the holder


14




a


. Thus, the photo-sensors


43


can determine how many holes


108


are made on the holder


100




a


in terms of the reflected beam of light, as for instance follows:




assuming that the CSP plate holder


100




a


of identification letter A has three holes


108


made therein; the CSP plate holder


100




b


of identification letter B has two holes


108


made therein; the CSP plate holder


100




c


of identification letter C has one hole made therein; and the CSP plate holder


100




d


of identification letter D has no hole made therein; and assuming that the holder


100




a


of identification letter A is above the putting in-and-taking out table


36


, three reflected beams of light are of least strength, and one reflected beam of light is of good strength, thus identifying the overlying holder as the one of identification letter A. The detection result is stored in the third memory means


49


.




The control means


45


makes a decision as to whether the contents of the first and third memory means


47


and


49


meet the CSP-to-jig correspondence relationship stored in the second memory means


48


. Specifically the identification number of the CSP plate stored in the first memory means


47


is


001


whereas the identification letter of the CSP plate holder stored in the third memory means


49


is A. Then, the CSP-to-holder correspondence relationship stored in the second memory means


48


is satisfied, so that the CSP plate holder


100




a


lying above the putting in-and-taking out table


36


is determined to be appropriate for holding the CSP plate


001


.




Thus, the putting in-and-taking out table


36


is raised to bear the jig holder


14




a


, as seen from FIG.


5


C. The putting in-and-taking out table


36


is moved in the −Y-axial direction to take out the CSP plate holder


100




a


from the rack


15


, and then, the putting in-and-taking out table


36


is raised up to the highest level (see FIG.


5


D), permitting the putting in-and-taking out table


36


to appear on the dicing machine


10


.




In case that the contents stored in the first and third memory means


47


and


49


fail to satisfy the CSP-to-holder correspondence relationship stored in the second memory means


48


, the CSP plate holder lying above the table


36


is determined to be inappropriate for holding the CSP plate


001


, and then the fact thus confirmed is given in the display


52


without taking out the CSP plate holder-from the rack


15


.




Even if a wrong CSP plate holder is stored in the address to which the putting in-and-taking out table


36


has an access, the taking out of the wrong holder can be avoided by allowing the decision-making means


44


to confirm that the holder does not meet the CSP-to-holder correspondence relationship relative to the selected CSP plate


11


.




Thus, the correct CSP plate holder


100




a


is put on the putting in-and-taking out table


36


. On the other hand, a selected CSP plate


11


is taken out from the cassette


12


by moving the CSP plate carrier


53


in the X-axial direction, putting the CSP plate


11


on the tentative storage station


54


.




In the tentative storage station


54


the conveyer belt


54




a


runs in the −X-axial direction, carrying the selected CSP plate


11


to a predetermined position where the CSP plate transporting means


55


transports the CSP plate


11


to the CSP plate holder


100




a


, which is laid on the putting in-and-taking out table


36


.




As shown in

FIG. 1

, the CSP plate transporting means


55


comprises a third guide rail


56


extending in the Y-axial direction, a drive


57


running on the guide rail


56


and an up-and-down unit


58


fixed to the drive


57


. The up-and-down unit


58


has suction means


59


. The up-and-down unit


58


is lowered to suck and hold the CSP plate


11


in the tentative storage station, and then, the up-and-down unit


58


is raised and moved in the −Y-axial direction to bring the CSP plate


11


to the jig holder


14




a


above. The up-and-down unit


58


is lowered to release the CSP plate


11


onto the jig holder


14




a


(see FIG.


8


).




Thus, the CSP plate


11


is put on the CSP plate holder


100




a


, which is laid on the putting in-and-taking out table


36


, and then, the CSP plate


11


along with the holder


100




a


are transported to the working table


61


by the first transport means


60


.




The first transport means


60


is composed of an elongated cantilever-like extension


62


and a gripper


63


movable along the cantilever-like extension


62


in the X-axial direction and vertically in the Z-axial direction. The gripper


63


has three suction pipes


64


for holding the CSP plate holder


100




a.






These suction pipes


64


are applied to the engagement holes


105




a


,


105




b


and


105




c


of the CSP plate holder


100




a


as shown in FIG.


2


. Negative pressure is applied to the overlying CSP plate


11


via the duct passages


106


and the second suction holes


104


to hold fixedly the CSP plate


11


on the CSP plate holder


100




a


by suction. Thus, the CSP plate


11


is fixedly gripped and brought by the gripper


63


to the working table


61


above. The gripper


63


is lowered toward the working extension


76


in the X-axial direction and vertically in the Z-axial direction, and a gripper


78


attached to the end of the arm


77


. As is the case with the first and second transport means


60


and


69


, the gripper


78


has three suction pipes


79


to engage with the engagement holes


29


,


30


and


31


of the CSP plate holder


100




a


for sucking and holding a diced CSP plate-and-holder combination.




When the diced CSP plate-and-holder combination is transported to the CSP plate bearing table


75


above by the gripper


78


, the gripper


78


is lowered while the suction pipes


79


are put away from the engagement holes


105




a


,


105




b


and


105




c


, thus landing and leaving the diced CSP plate-and-holder combination on the CSP plate bearing table


75


.




The CSP plate bearing table


75


can be moved in the Y-axial direction, and can be rotated, also. The CSP plate bearing table


75


is moved in the Y-axial direction to put the diced CSP plate-and-holder combination in position appropriate for picking up pellets one by one.




Transport trays are stored in the transport tray storage area


80


ahead of the CSP plate turning table


75


in the +X-axial direction. The pick up-and-transport means


81


extends from the CSP plate bearing table


75


to the transport tray storage area


80


above.




The pick-up and-transport means


81


comprises two movable pellet-suction means each movable both in the X-axial and Z-axial directions, each carrying a selected pellet and an elongated guide


82


which guides each movable pellet-suction means in the X-axial direction while it travels on the way from the CSP plate bearing table


75


to the transport tray station


80


.




The first transport tray bearing table


85


bears an empty transport tray


86


. The table


85


can be raised and lowered in the Z-axial direction, and can be moved in the Y-axial direction to crawl under the first transport tray rack


87


, in which a plurality of empty transport trays


86


are laid on each other to form a stack, and the lowermost transport tray is taken out by the table


85


. Then, the table


85


bearing an empty transport tray


86


returns to the transport tray storage area


80


.




To pick up and transfer each pellet from the diced CSP plate to a transport tray


86


the CSP plate bearing table


75


is moved in the Y-axial direction until the diced CSP plate-and-holder combination has been put in position in which a selected pellet is put below either gripper


83


. Then, the gripper


83


is lowered to suck the selected pellet, and the gripper


83


is raised. table


61


while putting the suction pipes


64


apart from the engagement holes


29


,


30


and


31


, thus allowing the CSP plate-and-holder combination to land and stay on the working table


61


. Then, negative pressure is applied to the CSP plate


11


via the first suction holes


103


, thereby holding fixedly the CSP plate-and-holder combination on the working table


61


.




Then, the working table


61


is moved in the −X-axial direction to the alignment means


66


below to detect the cutting lines


16


on the CSP plate


11


, so that the CSP plate


11


may be aligned with the cutting blade


67


in the Y-axial direction.




Movement of the working table


61


in the −X-axial direction permits the cutting blade


67


of the cutter means


68


to cut the CSP plate


11


along a selected longitudinal cutting line


16


. Every time the CSP plate has been cut along each longitudinal cutting line


16


, the CSP plate


11


is displaced the line-to-line interval distance in the Y-axial direction, and the working table


61


is reciprocated in the X-axial direction. Thus, the CSP plate


11


is cut along each and every longitudinal cutting line


16


.




Then, the working table


61


is rotated 90 degrees to permit the sequential cutting along each and every lateral cutting line


17


, thus dicing the CSP plate.




The diced CSP plate-and-holder combination is transported to the cleaning table


70


by the second transport means


69


. The second transport means


69


is composed of a movable arm


71


having an up-and-down grip


72


attached to its tip end. The movable arm


71


can be moved both in the X- and Y-axial directions, and the up-and-down grip


72


can be raised and lowered. The up-and-down grip


72


has three suction pipes


73


to be applied to the engagement holes


29


,


30


and


31


of the CSP plate holder


100




a.






The washing table


70


is substantially same as the working table in structure. It is a turn table having suction holes. When a CSP plate-and-holder combination is put on the washing table, it is rotated and exposed to the jet of washing water to remove minute pieces of debris from the upper surface of the diced CSP plate


11


. Finally it is dried by blowing air.




After being washed and dried, the diced CSP plate-and-jig holder combination is transported to the CSP plate table


75


by the third transport means


74


. The third transport means


74


is composed of a bridge-like extension


76


extending in the X-axial direction, an arm


77


movable along the bridge-like.




On the other hand, the transport tray


86


advances in the Y-axial direction in unison with the stepwise-movement of the first transport tray bearing table


85


in the Y-axial direction, so that the transport tray


86


may be aligned with the gripper


83


in the X-axial direction. Then, the gripper


83


gripping the selected pellet is moved in the +X-axial direction to transfer a selected pellet to a selected cell in the transport tray


86


above, and the gripper is lowered to release the selected pellet to the allotted cell.




The proceeding above described is repeated until all cells of the transport tray have been occupied by the pellets. In this particular embodiment two grippers


83


work in parallel efficiently.




After picking up all pellets, the CSP plate holder


14




a


is left on the CSP plate bearing table


75


, and then, the table


75


is made to turn 90 degrees, moving to the CSP plate holder storage area


88


in the +Y-axial direction. The fourth transport means


89


carries the holder


100




a


to the putting in-and-taking out table


36


. Then, another CSP plate is put on the CSP plate holder


100




a


to resume the dicing and transporting work.




When all CSP plates are diced and transported, the CSP plate holder


100




a


is returned to the CSP plate holder rack


15


to be pigeonholed at its original address. Advantageously the CSP plate holder


100




a


can be repeatedly used. In practice, four holders can be used simultaneously by moving them in unison.




The transport tray


90


thus filled with pellets is transferred to the second transport bearing able


92


by the transport means


91


. As shown in

FIG. 1

, the transport means


91


comprises a guide rail


91




a


, a transverse arm


93


movable along the guide rail


91




a


in the X-axial direction, and a pinch unit


94


fixed to the end of the transverse arm


93


. The pinch unit


94


is lowered to hold the pellet-filled transport tray


90


, and the pinch unit


94


is raised and moved in the +X-axial direction to carry the transport tray


90


to the second transport tray bearing table


92


above. The pinch unit


94


is lowered to release the transport tray


90


to the second tray bearing table


92


.




The second tray bearing table


92


can be moved both in the Y- and Z-axial directions inside the dicing machine. The table


92


is moved to the second transport tray rack


95


below, inserting the new pellet-filled transport tray into the bottom of a stack of pellet-filled transport trays in the second transport tray rack


95


.




As may be understood from the above, the dicing and transporting machine effects the dicing of each CSP plate, the washing of each diced CSP plate, the picking up of each pellet and the loading of transport trays with pellets. Thus, the series of works can be performed at an increased efficiency, and such machine is advantageous from the economical and productivity point of view.




A CSP plate can be sucked and fixedly held by an associated CSP plate holder simply by applying negative pressure from the suction sources


64


,


73


and


79


to the overlying CSP plate via its engagement holes


105




a


,


105




b


and


105




c


. There is no fear of allowing the CSP plate to fall on the way to a selected destination.




Referring to

FIG. 9

, a CSP plate


120


according to the second embodiment of the present invention is different from the CSP plates


100




a


and


100




b


of

FIGS. 2 and 3

only in that it has two minute through holes


121


made in each square section.




As described earlier, the CSP plate can be fixedly held by applying negative pressure from the suction sources


64


,


73


and


79


to the overlying CSP plate via the engagement holes


105




a


,


105




b


and


105




c


of the CSP plate while it is being diced or washed.




When pellets are picked up from a diced CSP plate one after another, and when each pellet is fixedly held by applying negative pressure from a selected through hole


103


, the through holes


103


are allowed to be exposed to the atmosphere one after another every time one pellet has been removed from the diced CSP plate. As a result, the surrounding air is allowed to be drawn from the open through holes, thus accordingly lowered the suction force. As a consequence, it is liable that pellets are allowed to deviate from their correct positions on the CSP plate holder


120


, thus making it difficult for the gripper


84


to pick up pellets from the diced CSP plate.




Referring to

FIG. 10

, minute through holes


121


are made to be independent from all of through holes


103


and suction holes


104


, and negative pressure can be applied to each pellet via the minute through holes


121


to hold fixedly the pellet when pellets are picked up from the diced CSP plate.




The resultant suction power at the two minute through holes for sucking and holding the overlying pellet must be lower than the suction power applied by the ripper


84


for sucking and removing the pellet from the underlying diced CSP plate. Also, each minute through hole should not draw a significant amount of air from the surrounding to allow the suction power to be reduced. The minute through hole


21


has a very small diameter, preferably ranging from 0.2 to 0.4 millimeters.




Some CSP plates may be somewhat bent, and cannot be fixedly held on CSP plate holders. Referring to

FIG. 12

, rubber or elastomeric sheets


130


are laid on CSP plates


120


to compensate for their bends, thus permitting CSP plates to hold fixedly the overlying CSP plates (see FIG.


13


).




The elastomeric sheet


130


has different apertures made in conformity with the through holes


103


, suction holes


104


and minute through holes


121


of the overlying CSP plate holder


120


, but it is not necessary to cut “in let” grooves because the cutting blade cannot be broken when it conflicts with the elastomeric sheet


130


. As a matter of course, such elastomeric sheets can be applied to CSP plate holders


100




a


and


100




b


of

FIGS. 2 and 3

.




The elastomeric sheet


130


may be applied to the CSP plate holder by an adhesive agent, which is responsive to ultraviolet rays for reducing its adhesive strength. When such elastomeric sheet


130


is deteriorated after repeated use, and when it needs to be changed for a new elastomeric sheet, exposure of the used sheet to ultraviolet radiation will facilitate the peeling-off of used sheet from the CSP plate holder.




To suck and hold each pellet by applying a negative pressure to the pellet via the minute through holes it is necessary that the CSP bearing table be so constructed as to permit application of negative pressure to the pellet through each minute through hole.




Referring to

FIG. 14

, the CSP bearing table


140


comprises a base


143


and a table


144


fixed to the top of the base


143


. The base


143


rides on two parallel guide rails


142


. An elongated screw rod


141


is connected to the shaft of an associated electric motor (not shown), extending between the opposite guide rails


142


in the Y-axial direction. The base


143


is threadedly engaged with the screw rod


141


, and it can be driven in the Y-axial direction by the electric motor.




As shown, the table


144


has duct passages


145


to communicate exclusively with the minute through holes


121


of the overlying CSP plate holder


120


. These duct passages


145


do not communicate with the through holes


103


, so that the through holes


103


of the CSP plate holder


120


may be closed when it is put on the table


144


. Thus, the diced CSP plate is held by applying a controlled negative pressure to each pellet area via the minute through holes


121


, thereby facilitating the picking up of each pellet from the diced CSP plate; each pellet is retained in its correct position, and is sucked and held with a relatively weak suction force.




As may be understood from the above, CSP plate holders according to the present invention can be repeatedly used, and can fixedly hold CSP plates simply by applying negative pressure to them. Thus, any disposable such as adhesive tapes needs to be used, and therefore, removal and collection of used adhesive tapes and application of new adhesive tapes to CSP plates and associated frames are not required. There is, therefore, no problem of pollution, and the productivity can be improved accordingly.




The controlled sucking of CSP plates and diced CSP plates assures the reliable setting and holding of such plates in dicing and; transporting.




Use of elastomeric sheets permits CSP plates even though bent more or less to be fixedly held on the CSP plate holders. Elastomeric sheets may be applied to CSP plate holders with an ultraviolet rays-sensitive adhesive agent, and then used sheets can be easily peeled off to be changed with new ones.



Claims
  • 1. A CSP plate holder for use in dicing a CSP plate into individual pellets, the CSP plate holder comprising:a solid block operative for bearing the CSP plate thereon and having a first surface, a second surface disposed opposite the first surface and a thickness extending therebetween in a thickness direction to define a side surface extending about and between the first and second surfaces, the solid block having a plurality of pellet areas formed on the first surface with each pellet area allotted to a respective one of the individual pellets, a plurality of bores extending entirely through the solid block between the first and second surfaces, each bore allotted to a respective one of the pellet areas, a plurality of suction holes formed on the first surface and partially into the solid block with at least one suction hole allotted to a respective one of the pellet areas and a labyrinth of suction passages formed interiorly of the solid block, the labyrinth of suction passages including at least one suction passage opening formed into the side surface and being in fluid communication with each one of the plurality of suction holes and exteriorly of the solid block at the suction passage opening, the plurality of bores, the plurality of suction holes and the labyrinth of suction passages disposed in a manner such that the plurality of the bores are in fluidic isolation from the plurality of suction holes and the labyrinth of suction passages.
  • 2. A CSP plate holder according to claim 1, wherein the solid block includes a plurality of crisscrossing grooves forming a pattern defining the plurality of the pellet areas.
  • 3. A CSP plate holder according to claim 1, wherein solid block includes an identification mark.
  • 4. A CSP plate holder according to claim 1, further comprising an elastomeric sheet laid on the first surface of said solid block.
  • 5. A CSP plate holder according to claim 4, wherein said elastomeric sheet is made of a synthetic resin.
  • 6. A CSP plate holder according to claim 5, wherein said elastomeric sheet is applied to the first surface of said solid block by an adhesive agent, which is sensitive to ultraviolet rays for reducing its adhesive power.
  • 7. A CSP plate holder according to claim 3, wherein the indentification mark is a selected number of identification holes linearly aligned and formed into the first surface.
  • 8. A CSP plate holder according to claim 1, wherein the solid block is rectangularly shaped forming two pairs of opposing sides surfaces and the labyrinth of suction passages extends perpendicularly to the thickness direction.
  • 9. A CSP plate holder for use in dicing a CSP plate into individual pellets, the CSP plate holder comprising:a flat plate operative for bearing the CSP plate thereon and having a first surface, a second surface disposed opposite the first surface and a thickness extending therebetween in a thickness direction to define a side surface extending about and between the first and second surfaces, the flat plate having a plurality of pellet areas formed on the first surface with each pellet area allotted to a respective one of the individual pellets, a plurality of through holes extending through and between the first and second surfaces, each through hole allotted to a respective one of the pellet areas, a plurality of suction holes formed on the first surface and partially into the flat plate with at least one suction hole allotted to a respective one of the pellet areas and a labyrinth of suction passages formed interiorly of the flat plate, the labyrinth of suction passages including at least one suction passage opening formed into the side surface and being in fluid communication with each one of the plurality of suction holes and exteriorly of the flat plate at the suction passage opening, wherein the flat plate is rectangularly shaped forming two pairs of opposing sides surfaces and the labyrinth of suction passages extends perpendicularly to the thickness direction and wherein the flat plate includes at least two suction openings with one suction opening formed into one side surface of a selected pair of side surfaces and a remaining suction opening formed into an opposing side surface of the selected pair of side surfaces.
  • 10. A CSP plate holder for use in dicing a CSP plate into individual pellets, the CSP plate holder comprising:a flat plate operative for bearing the CSP plate thereon and having a first surface, a second surface disposed opposite the first surface and a thickness extending therebetween in a thickness direction to define a side surface extending about and between the first and second surfaces, the flat plate having a plurality of pellet areas formed on the first surface with each pellet area allotted to a respective one of the individual pellets, a plurality of through holes extending through and between the first and second surfaces, each through hole allotted to a respective one of the pellet areas, a plurality of suction holes formed on the first surface and partially into the flat plate with at least one suction hole allotted to a respective one of the pellet areas and a labyrinth of suction passages formed interiorly of the flat plate, the labyrinth of suction passages including at least one suction passage opening formed into the side surface and being in fluid communication with each one of the plurality of suction holes and exteriorly of the flat plate at the suction passage opening, wherein the flat plate is rectangularly shaped forming two pairs of opposing sides surfaces and the labyrinth of suction passages extends perpendicularly to the thickness direction and wherein the flat plate includes three suction openings with two suction openings formed into one side surface of a selected pair of side surfaces and a remaining suction opening formed into an opposing side surface of the selected pair of side surfaces.
Priority Claims (1)
Number Date Country Kind
11-257256 Sep 1999 JP
US Referenced Citations (10)
Number Name Date Kind
3809050 Chough et al. May 1974 A
3811182 Ryan, Sr. et al. May 1974 A
3976288 Cuomo, Jr. Aug 1976 A
4600936 Khoury et al. Jul 1986 A
5605489 Gale et al. Feb 1997 A
5618759 Boysel Apr 1997 A
5641714 Yamanaka Jun 1997 A
5964646 Kassir et al. Oct 1999 A
6024631 Piper Feb 2000 A
6165232 Tieber et al. Dec 2000 A