JPH0376247A - Transfer of wafer - Google Patents

Abstract

PURPOSE:To make it unnecessary to transfer a wafer from one cassette to another after the wafer is processed by a method wherein processed wafers are housed in the cassettes of a pool section one by one from the top cassette, then the wafers are taken out one by one from the bottom and then housed in a cassette of an unload section one by one from the top first. CONSTITUTION:Wafers 3a, 3b, 3c,... are successively taken out in this sequence from the lower part of a cassette 2, which is made to descend by one pitch at each delivery of a wafer, and processed, and then the processed wafers 3a, 3b, 3c,... are successively housed in this order in a cassette 105 on a table 101, which is made to ascend from the lowermost position pitch by pitch, from the top first. During this operation, the cassette 2 which becomes empty at a load section is placed on a table 90 at the lowermost position at an unload section, the processed wafers in the cassette 105 are taken out from the lower part of the cassette 105, which is made to descend from the uppermost position, and then successively housed in the cassette 2 on the table 90, which ascends pitch by pitch, from the top first. The processed wafers are housed in the cassette 2 at an unload section in the same order with the wafers in the cassette 2 loaded at a load section at first.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves attaching an adhesive tape to the top of a wafer of any shape, such as a circular shape, such as a silicon wafer that serves as a substrate for an integrated circuit, and applying this tape to the top of the wafer. The present invention relates to a method for transferring a wafer in a wafer processing apparatus, such as an apparatus that peels off tape other than the portion stuck on the wafer after cutting along the outer periphery.

[Conventional technology]

As a conventional wafer processing apparatus, for example, Japanese Patent Application Laid-Open No. 64-43
In the method disclosed in Japanese Patent No. 458, a wide adhesive tape is attached to a wafer, and the attached tape is cut along the periphery of the wafer.

In this known technology, a loading section and an unloading section are provided at the front of both ends of a processing section that performs the above-mentioned processing, and the wafers are taken out one by one from the lower part of a cassette in the loading section and are processed in the processing section. The finished wafers are transferred to the rear of the unloading section, and loaded one by one into a cassette in the unloading section from the top.

[Problem to be solved by the invention]

In the above-mentioned known technology, the wafers taken out one by one from the bottom of the cassette in the loading section are stored one by one from the top of the cassette in the unloading section. is at the top of the cassette in the unloading section, and the order in which the cassettes are stored is reversed. If it is inconvenient to send the cassette as it is to the next process, use the transfer device to restore the original order. Is required.

Furthermore, since the cassettes for the loading section and the unloading section are separate, a special transfer device is required to return the processed wafer to the cassette of the loading section.

An object of the present invention is to provide a method for transferring wafers that does not require transferring wafers between cassettes after processing, in order to solve the problems of the prior art as described above.

[Means to solve the problem]

In order to solve the above problems, the present invention includes a loading section that takes out a plurality of wafers housed in a cassette one by one from the bottom and sends them out to a processing section, and a loading section that takes out a plurality of wafers housed in a cassette one by one from the bottom and sends them to a processing section, and a load section that takes out a plurality of wafers housed in a cassette one by one and sends them to a processing section, and a loading section that loads processed wafers into the cassette from the top in the processing section. In a wafer processing apparatus equipped with an unloading section for accommodating wafers one by one, a pool section is provided behind the unloading section, and a wafer cassette/
The wafers are taken out one by one from the bottom of the pool and processed in the processing section.The wafers are then stored one by one in the cassettes of the pool section from the top, and then the cassettes of the pool section are taken out one by one from the bottom and unloaded. To provide a method for transferring wafers by storing them one by one in a cassette of a loading part from the top.

〔Example〕

An apparatus for attaching tape to a wafer as an example of a processing apparatus for carrying out the method of the present invention will be described below.

1 in FIG. 1 is a loading section and has a pair of left and right stands 14 on which cassettes 2 containing wafers 3 are placed. As shown in FIG. 3, a large number of wafers 3 are stacked at appropriate intervals in the cassette 2 on the left and right stands 14 with the element formation side facing up, and are moved to the lowest position in the cassette 2 by an endless conveyor belt 4.5.6. wafer 3
The guide table 7 is divided into a plurality of parts as shown in FIG. 9 is fixed.

The belt 8 is bent by a plurality of pulleys to prevent it from interfering with the belt 6, as shown in FIG.
When the wafer 3 is driven by the motor 10 and the transmission belt 11 in the direction of the arrow in FIG. 2, the wafer 3 is fed into the next wafer alignment means 15.

Each table 14 is raised and lowered by a lifting means (not shown), and every time one wafer 3 is taken out, the cassette 2
is lowered and the next wafer 3 is placed on the belt 4.

The cassette 2 on one of the stands 14 is provided with stands 14 on the left and right sides.
When the cassette 2 becomes empty, the wafer 3 in the other cassette 2 is taken out and the operation continues, and during this time the empty cassette 2 is transferred to the wafer 3
This is to increase the operating rate of the device by replacing it with the cassette 2 containing the .

In the case of a device in which only one cassette is set in the load section, only one stand 14 is required, and that position is located at the belt 8.
It may be placed at any position on the upper facing portion.

The wafer alignment means 15 is provided with a guide bar 17 on the outer upper part of the left and right pedestals 16, and a pair of left and right endless conveyor belts 18 are arranged between both the pedestals 16.

The conveyor belt 18 is a transmission belt 2 as shown in FIG.
0.21, the belt 18 runs in synchronism with the conveyor belt 8. The belt 18 is provided on an elevating frame 23 on a machine stand 22, and this frame 23 is raised and lowered by an air cylinder 19.

The wafer alignment means 15 is as shown in FIG. 2 and FIGS. 4 to 6.

That is, a lever 25 that swings around a horizontal axis 24 is provided on the frame 23, and a groove pulley 27 that is rotated around a vertical axis by a motor is provided on this lever 25.
As shown in Fig. 6, three rotating rods 31 are attached to the mounting base 28 on the top of the mount 5.
-532, 33 are provided, and the endless belt 26 is engaged with the groove pulley at the lower end of each of these rods and the groove pulley 27, so that the rotary rods 31, 32, 33 rotate as shown by the arrows in FIG. The center rotating rod 32 is moved slightly forward.

Further, the lever 25 can be swung up and down by an air cylinder 35.

Reference numeral 36 in FIGS. 2 and 5 is a lever that is coaxial with the horizontal shaft 24 and swings separately from the lever 25.
A stopper 37 is attached.

This stopper 37 precisely positions the straight edge of the wafer 3, that is, the orientation flat 12, and has a mechanism that allows fine adjustment of the contact surface by rotating around the rotation axis 39 and fixing it at an arbitrary angle. There is.

Further, the lever 36 mentioned above is swung up and down by an air cylinder 38.

In the above alignment means 15, initially as shown in FIG.
As shown in FIG. 4, three rotating rods 31, 32, 33 and a stopper 37 protrude above the conveying surface of the belt 18. Therefore, the outer circumference of the wafer 3 transported by the belt 18 is
1.32.Touches the outer circumference of 33. In the case of an arcuate edge of the wafer 3, all the rods 31, 32, 33 are in contact with the wafer 3, but the wafer 3 has two adjacent rods 3 rotating in the same direction.
2.33 It is turned by friction with 33. When the wafer 3 rotates and its orientation flat 12 comes to the rods 31, 32, and 33, the central support 32 separates from the orientation flat 12 as shown in FIG. 31 and 33 are in contact with each other, the wafer 3 stops with the orientation flat 12 facing forward.

As described above, it is detected that the wafer 3 is at the position of the alignment means 15, and the rotating rods 31, 32, 33 are rotated, and the alignment of the orientation flat of the wafer 3 is completed, that is, the orientation flat 12 is in contact with the rotating rod 31, 33. Detecting this, the rotation of the rotating rods 31, 32, 33 is stopped, and at the same time the cylinder 35 is stopped.
lower it by At this time, the wafer 3 moves forward on the belt 18, and its front orientation flat 12 contacts the stopper 37 as shown by the chain line in FIG. 1 and FIG. 5, and is positioned more precisely here.

This stopper 37 has the above-mentioned fine adjustment function and can perform angle adjustment with extremely high precision.

When a photoelectric detector or the like detects that the wafer 3 has reached this point, the air cylinder 1S operates to lower the belt 18 together with the frame 23 and move the wafer 3 onto the moving stage 40. After confirming the wafer on the stage 40, the air cylinder 38 is activated. Then, the stopper 37 is lowered as shown by the chain line in FIG.

The moving stage 40 has left and right belts 1 as shown in FIG.
It is a hollow vacuum suction type having a large number of vacuum suction holes on the upper surface, and is attached to the tip of an arm 42 that moves forward and backward by forward and reverse rotation of a feed screw 41.

Further, the feed screw 41 is supported by a bearing on the base 22 and is driven by a forward/reverse motor 43 .

Therefore, under the condition that the belt 18 is lowered and the wafer 3 is moved onto the moving stage 40, vacuum suction is performed, and the stopper 37 is lowered as described above, the screw 41 is rotated forward by the motor 43, and the arm 42 is rotated to the left as seen in FIG. The wafer 3 is then moved between the bonding rollers 45 and 46.

The bonding rollers 45 and 46 are made of a flexible elastic body such as rubber, and the upper roller 45 is provided with an appropriate reduction blade by a balance weight mechanism (not shown).
The lower roller 46 is connected to a drive control unit 47 including a motor.
drive or brake. That is, an electromagnetic clutch and a torque damper (not shown) are provided on the drive shaft of the roller 46, so that when the clutch is connected, a brake is applied to the roller 46, and intermittent drive is also possible by installing a clutch and a motor. becomes.

In addition, as shown in FIG.
2 is provided, and the tape 51 fed out from the reel 50 passes through the guide roller 53 and between the upper and lower rollers 45 and 46 with the adhesive side facing down, and then passes through the tape peeling means 54 to be described later.
A guide roller 57 provided in the machine box 48 passes between the lower peeling roller 55 and the pair of upper and lower peeling rollers 66.
, and is wound onto a take-up reel 52 via a tension roller 58.

Further, the separator 60 is wound onto a take-up reel 63 via a separator winding roller 61 and a pinch roller 62.

As described above, the bonding roller 45 is mounted on the moving stage 40.
．． At the same time as the wafer 3 is inserted between the spaces 46 and 46, the vacuum suction of the stage 40 is released, the motor 43 is reversed and the stage 40 is returned to its original position, and the frame 23 and levers 25 and 36 are also raised to their original positions to move on to the next stage. It enters the wafer receiving state.

On the other hand, the wafer 3 fed between the bonding rollers 45 and 46 as described above is moved to the tape cutting means 65 with the adhesive tape 51 affixed to its upper surface, and the wafer 3 is moved to the tape cutting means 65, which is cut by a plurality of It is positioned by the photoelectric detector 69 and stopped.

The tape cutting means 65 is provided on a lifting frame 67 shown in FIG. 2 that is raised and lowered by a vertical air cylinder fixed to the inner surface of the side wall of the machine box 48.

A movable table 71 that moves forward and backward in a direction perpendicular to the conveying direction of the wafer 3 is provided at the lower part of the elevating frame 67 using an air cylinder, and a vertical cylinder 72 is fixed to the movable table 71 facing downward.

Reference numeral 75 denotes a rotary support plate provided at the lower end of the cylindrical body 72, and an adjustment plate 76 movable in the horizontal direction along a guide is provided at the bottom of this support plate 75. The adjustment plate 76 is moved horizontally and fixed at an arbitrary position to match the cut size.

A sliding body 77 that is moved by a feed screw is provided at the bottom of the adjustment plate 76, a frame 78 is provided on the side of this sliding body 77, a cutter 79 is provided at the lower end of this frame 78, and a vacuum suction type stage 80 is mounted. The adhesive tape 51 attached to the wafer 3 is cut along the periphery of the wafer 3. The stage 80 has a large number of suction holes or suction grooves on its upper surface,
The wafer 3 that has been moved thereon is fixed by vacuum suction, and although it can be raised and lowered by an air cylinder 81 shown in FIG. 2, it may also be fixed.

In addition, two grooves 85 are provided on the upper surface of the stage 80 parallel to the direction of movement of the wafer 3, and an endless conveyor belt 82 for conveying the wafer to the sea urchin is inserted into the grooves 85, as shown in FIG. The movable frame 83 to which this conveyor belt 82 is attached is raised and lowered by an air cylinder 84, and the belt 8
The conveying surface of No. 2 is arranged to appear and retract from the upper surface of the stage 80.

However, if a conveyance method using the buoyancy of air is used, the groove 85 is not necessary and the belt 82 may be short. In this case, the stage 80 may be provided with an air blowing nozzle for conveyance other than the suction hole The suction hole and air blowing nozzle can be used together and switched by the air circuit.

Further, guide stands 29 and 30 are provided around the stage 80 as shown in FIG. 1, and guide bars 34 are provided on both sides of the guide stand 30.

As shown in FIG. 1, the tape peeling means 54 is provided with the peeling roller 55 and upper and lower peeling rollers 56 on a movable table 87 that moves forward and backward by forward and reverse rotation of a feed screw 86. The upper and lower rollers 56 are rotated in opposite directions by gears. It is interlocked so that it rotates in the direction of rotation.

Further, the feed screw 86 is driven by a forward/reverse motor (not shown).

As shown in FIGS. 1 and 2, the peeling means 54 stops at the positioning stop position, and the wafer 3 is stuck to the lower part of the tape 51 stuck between the bonding roller 45, 46 and the peeling roller 55, In addition, under the condition that this wafer 3 is placed on the rising stage 80 and the belt 82 is falling and its conveying surface is below the upper surface of the stage 40, an air cylinder (not shown) works to move the lifting frame 67. is lowered, the frame 78 turns, and the cutter 79 cuts the tape on the wafer 3.

With the above action, the blade 79 completely cuts the tape 51, and at the same time as the blade 79 is raised together with the lifting frame 67, the blade 79 returns to its origin, and the roller 46 is braked to stop the movement of the tape 51. The feed screw 86 rotates normally and moves the peeling means 54 rightward toward FIGS. 1 and 2.

As a result, the tape 51 is peeled off leaving the tape stuck on the wafer 3.

Then, the cylinders 81 and 84 are actuated to lower the stage 80 and raise the frame 83 to transfer the wafer 3 from the stage 80 onto the belt 82. At the same time, the belt 82 is driven to transport the wafer 3 between the next unload section 88 and pool section 89.

The unloading section 88 has a function opposite to that of the loading section 1, and as shown in FIG. 1, it consists of a pair of left and right platforms 90 on which the cassettes 2 from the loading section 1 are placed, and an elevating device therefor.
A guide stand 91 is provided at the rear.

The guide stand 91 is divided into a plurality of parts, and a pair of left and right endless conveyor belts 92 following the endless conveyor belt 82 are provided between them, and a belt (belt) is provided between the belt S2 and each stand 90.
A pair of left and right endless conveyor belts 93, 94, perpendicular to 92.
95 are arranged one after another, and the wafers 3 thereon are fed into the cassette 2 on the table 90.

The conveyance side of the belt 92 is bent by a plurality of pulleys as shown in FIG.
Drive in the direction of the arrow in the figure.

In addition, the endless conveyor belt 82 is an endless transmission belt) 98
．． 99 is linked to the belt 92.

The pool section 89 also has a pair of left and right stands 10 as shown in Figure 1.
1 will be provided. A pair of left and right endless conveyor belts 102 and 103 are sequentially arranged behind each of the belts 93 so that the wafers 3 on the belts 93 are conveyed to the cassette 105 on the table 101.

The drive device for each of the belts 93, 94, 95, 102, and 103 described above is capable of forward and reverse rotation.

Since the cassette 105 is intended to temporarily accommodate the wafers 3, there is no need to move the cassette 105, so it may be a cassette-like accommodating portion integrated with the table 101.

The wafer 3 sent between the unloading section 88 and the pool section 89 as described above is placed on the predetermined belt 93 on the right or left side as shown in FIGS.
stops, belt 93, S4.102.103.104
starts rotating backward and feeds the wafer 3 into a cassette 105 on a predetermined table 101.

The platform 101 is a known device that increases each time one wafer 3 is fed into the cassette 105. For example, if the cassette 105 on the platform 101 on the left side of FIG.
The wafer 3 is fed into the cassette 105 on the right stand 101, while the belt 103.1 belonging to the left stand 101 is fed.
02.93.94.95 started running in the opposite direction, leaving platform 1 on the left.
The wafers 3 in 01 are taken out one by one starting from the bottom, and fed one by one from the top into the cassette 2 on the stand 90 on the left side of the lowest position.

If the cassette 105 on the right stand 101 becomes unstable, it may interfere with the operation of storing the cassette 105 on the left stand 101.

In this case, processing of the work is temporarily stopped and the work is transferred at the end of the loft.

Therefore, each time a wafer 3 is taken out from the bottom of the cassette 105, the right stage 101 moves down one pitch, and the right stage 90
increases by one pitch each time a sheet is fed into the upper part of the cassette 2.

The operation of feeding the wafer 3 into the cassette 105 on the left stage 101 and feeding the wafer 3 in the left cassette 105 into the left cassette 2 is also the same as described above.

In order to ensure that the wafer 3 is correctly fed into the cassette 105 on the right or left stand 105 as described above, a stopper 107 is provided between the left and right belts 92 that is moved up and down by an air cylinder 106, and a stopper 107 is provided between the left and right belts 92, and a stopper 107 is provided between the left and right belts 92, and a A stopper 108 is provided on the left and right guide stands 91, and a guide bar 109 is provided on the left and right guide stands 91. When sending the wafer 3 to the left cassette 105, the wafer 3 is moved to the stopper 10 by lowering the stopper 107. When feeding the wafer 3 into the cassette 105 on the right side, the stopper 107 is raised and the wafer 3 is stopped by the stopper 108.
Make it possible to stop at 7.

The unloading section 88 and the pool section 89 are also connected to the loading section 1.
Similarly, in the case of only one cassette, the stands 90, 101 can be provided at one arbitrary position on the opposing portions of the belt 92.

The method of transferring wafers using the above device is shown in Figure 7.
A more detailed explanation will be given based on , ■, and ■.

That is, as shown by ■ in FIG. 7, the wafers are placed in the cassette 2 on the table 14 of the load section at the highest position from the bottom 3a,
If they are stored in the order of 3b, 3C...
- Every time a wafer is sent out - The wafers are sequentially taken out from the bottom of the cassette 2 in the order of 3a, 3b, 3C, etc., which moves down in pitch, and are processed. 3a, 3b, 3C, . . . are stored in the order of cassettes 3a, 3b, 3C, .

During this time, the empty cassette 2 in the loading section is placed on the platform 90 at the lowest position of the unloading section, and the processed wafers in the cassette 105 are transferred to the cassette 105 that is descending from the highest position. When the wafers are taken out one by one from the bottom and placed in the cassette 2 on the table 90 that rises by - pitch from the top, the wafers in the cassette 2 that were initially in the loading section are removed as shown in Fig. 7 (■). The processed wafers are stored in the cassette 2 of the unloading section in the same order.

〔Effect of the invention〕

In this invention, as described above, the wafers are taken out one by one from the lower part of the cassette in the loading section, processed by applying adhesive tape and cut, and then the processed wafers are placed in the upper part of the cassette in the pool section. When the cassette in the pool section becomes empty, the processed wafers taken out one by one from the lower part of the pool section are sequentially fed into the cassette in the unloading section from the top to another transfer device. Processed wafers can be stored in the same cassette in the same order as unprocessed wafers stored in the first cassette without using a cassette.

Therefore, there are advantages such as no need for a separate transfer device or a cassette dedicated to the unloading section as in the conventional method.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the apparatus for carrying out the method of the present invention, FIG. 2 is a front view of the same, FIG. 3 is an enlarged longitudinal sectional side view of the vicinity of the cassette in the loading section, FIGS. The figure is a partially longitudinal enlarged front view showing each state of the alignment means.
FIG. 6 is a plan view of the essential parts of the same, and FIGS. 7 (2), (2), and (3) are longitudinal sectional side views showing the order of wafer transfer. 1... Load section, 2.105...
...Cassette, 3...Wafer, 15...Wafer alignment means, 51...
... Adhesive tape, 54 ... Tape peeling means, 65 ... Tape cutting means, 88 ... Unloading section, 89 ... Pool section.

Claims (1)

[Claims] (1) A loading section that takes out a plurality of wafers housed in a cassette one by one from the bottom and sends them to the processing section, and an unloading section that stores the wafers processed in the processing section one by one into the cassette from the top. In a processing device for wafers, a pool section is provided behind the unload section, the wafers are taken out one by one from the bottom of the cassette in the loading section, and the wafers processed in the processing section are placed into the cassette in the pool section from the top. A method for transferring wafers, which comprises storing the wafers one by one, then taking out the wafers one by one from the lower part of the cassette in the pool part, and storing the wafers one by one in the cassette of the unloading part from the upper part.