Information
-
Patent Grant
-
6386191
-
Patent Number
6,386,191
-
Date Filed
Thursday, August 31, 200024 years ago
-
Date Issued
Tuesday, May 14, 200223 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Rader, Fishman & Grauer, PLLC
-
CPC
-
US Classifications
Field of Search
US
- 451 388
- 125 35
- 125 1301
- 269 21
-
International Classifications
-
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)