JP3209403B2 - Wafer cleaning equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a wafer cleaning apparatus, and more particularly to a wafer cleaning apparatus for cleaning wafers in a batch state that are cut into a comb by a wire saw.

[0002]

2. Description of the Related Art In a wire saw, when cutting an ingot, a slice base is bonded to the ingot in order to prevent the end of the ingot from being broken. For this reason, all the wafers to be cut out are cut out in a state of being bonded to one slice base, that is, in a so-called batch state.

On the other hand, the chamfering step, the lapping step, etc., which are steps after cutting with a wire saw, all process wafers one by one. Therefore, the wafer in a batch state cut with the wire saw is peeled off from the slice base. It is necessary to make a sheet. The wafers in the batch state are peeled and separated into single wafers by a dedicated peeling device. However, the wafers immediately after the cutting by the wire saw are extremely dirty with slurry or sludge adhered at the time of the cutting. For this reason, the wafers in the batch state are cleaned prior to the peeling by the peeling device and the sheet formation.

Heretofore, the following method has been employed as a method for cleaning a wafer in a batch state of this kind. That is, a plurality of cleaning tanks equipped with an ultrasonic oscillation device are prepared, and the wafers are washed by sequentially immersing the wafers in the cleaning tanks and gradually increasing the degree of cleaning.

[0005]

However, when a wafer is cleaned by the above-described method, a plurality of cleaning tanks are required, so that the size of the apparatus is disadvantageously increased.
In addition, when the number of cleaning tanks is increased, when automated, a wafer transfer device between the cleaning tanks is required.
Further, there is a drawback that the apparatus becomes large.

Further, when the number of cleaning tanks is large, it is necessary to manage the cleaning liquid (liquid amount, liquid temperature, liquid supply, drainage, etc.) for each cleaning tank, which is disadvantageous in that it is extremely troublesome. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a wafer cleaning apparatus that can effectively clean a wafer with one cleaning tank.

[0007]

According to the present invention, there is provided a wafer cleaning apparatus for cleaning a wafer cut with a wire saw and having one end thereof adhered to a slice base in order to achieve the above object. A cleaning tank capable of storing and draining a cleaning liquid, a support member provided to be vertically movable with respect to the cleaning tank, and supporting a wafer housed in the cleaning tank; Vertical driving means for moving, a nozzle which is movably supported along the axial direction of the wafer accommodated in the cleaning tank, and which sprays a cleaning liquid toward the wafer accommodated in the cleaning tank; and Reciprocating drive means for reciprocating the nozzle, the cleaning liquid being jetted toward the wafer contained in the cleaning tank while reciprocating the nozzle, and As well as cleaning and post injection cleaning of the cleaning liquid, the cleaning liquid stored in the cleaning tank, characterized by cleaning the wafer by vertically moving the wafer.

[0008]

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a wafer cleaning apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. 1 and 2 are a front view and a side view, respectively, showing the overall configuration of a wafer cleaning apparatus according to the present invention.

As shown in FIG. 1, the wafer cleaning apparatus 10 includes a cleaning apparatus main body 12 for cleaning a wafer W,
And a lifter 60 for carrying the wafer W into and out of the cleaning apparatus main body 12. First, the configuration of the cleaning device main body 12 will be described. 3 and 4 are a front view and a plan view of the cleaning device main body 12, respectively. FIGS. 5 and 6 are cross-sectional views taken along line AA of FIG.
It is B sectional drawing.

As shown in FIGS. 3 to 6, the cleaning apparatus main body 12 has a cleaning tank 14 having an open upper part.
A frame 1 formed in a rectangular shape is provided on an upper portion of the cleaning tank 14.
6 is integrally fixed to the cleaning tank 14. The frame 16
Inside, a pair of cleaning liquid supply pipes 18A and 18B is arranged along the longitudinal direction of the frame body 16. The cleaning liquid supply pipes 18A and 18B are rotatably and slidably supported by the frame 16 via a bush (not shown).

The pair of cleaning liquid supply pipes 18A, 18
In B, six nozzles 20A and 20B are arranged at a constant pitch along the axial direction. Also,
Flexible tubes are connected to one ends of the cleaning liquid supply pipes 18A and 18B via joints 22A and 22B. A cleaning liquid supply device (not shown) is connected to the tubes 24A and 24B, and the cleaning liquid supplied from the cleaning liquid supply device is supplied to the tubes 24A and 24B.
The cleaning liquid is supplied to the cleaning liquid supply pipes 18A and 18B via 4B. And the cleaning liquid supply pipes 18A, 18
B, the cleaning liquid supplied to the nozzles 20A, 20B
Injected from. The cleaning liquid sprayed from the nozzles 20A and 20B hits the wafer W stored in the cleaning tank 14, and the wafer W is shower-cleaned.

As described above, the cleaning liquid supply pipes 18A and 18B are supported rotatably and slidably with respect to the frame 16. Therefore,
If the cleaning liquid supply pipes 18A, 18B are slid, the nozzles 20A, 20B are also slid, and if they are rotated, they are simultaneously rotated (oscillated). The sliding and rotation of the cleaning liquid supply pipes 18A and 18B are performed by driving units 26A and 26B provided at one end of the cleaning liquid supply pipes 18A and 18B. The driving units 26A and 26B are configured as follows. Is done. In addition,
Since the drive units 26A and 26B have the same configuration,
Only the configuration of the drive unit 26A will be described.

FIG. 7 is a sectional view of a main part showing the structure of the drive unit 26A. As shown in the figure, a supporting member 28A formed in a cylindrical shape is fixed to the side surface of the frame 16. The cleaning liquid supply pipe 18A is inserted through the inner periphery of the support member 28A, and the main frame 30A of the driving unit 26A and the driving gear 3 are inserted through the outer periphery.
2A is rotatably supported.

A ball screw 34A is rotatably supported on the body frame 30A in parallel with the cleaning liquid supply pipe 18A. A nut member 36A is screwed into the ball screw 34A.
Is connected to the cleaning liquid supply pipe 18A. A driven gear 38 is provided at one end of the ball screw 34A.
A is fixed, and the driven gear 38A is meshed with a drive gear 32A rotatably supported by the support member 28A.

With the above configuration, when the drive gear 32A rotates, the rotation is transmitted to the driven gear 38A, and the ball screw 34A fixed to the driven gear 38A rotates. When the ball screw 34A rotates, the nut member 36A screwed to the ball screw 34A is rotated.
Moves along the ball screw 34A, and as a result, the cleaning liquid supply pipe 18A slides along its axis.

Here, as shown in FIG. 3, the driving gear 32A is provided with a motor 4 provided on the side surface of the cleaning tank 14.
The rotation of 0 is transmitted via the timing belt 42, and is thereby driven to rotate. Therefore, the drive gear 32
7A shows the timing belt 42 as shown in FIG.
Is integrally formed with the pulley 44A for winding the wire.

A forward / reverse motor is used as the motor 40. The forward / reverse rotation is repeated at regular intervals, whereby the cleaning liquid supply pipe 18A reciprocates along its axis. The above configuration is a mechanism for slidingly moving the cleaning liquid supply pipe 18A. Next, a mechanism for swinging the cleaning liquid supply pipe 18A will be described.

As shown in FIG. 3, a pair of hydraulic cylinders 46A and 46B are swingably supported on the side surface of the cleaning tank 14 via brackets 48A and 48B, respectively. The rod end portions of the pair of hydraulic cylinders 46A, 46B are connected to the body frames 30A, 30B of the swing units 26A, 26B by pins.
Therefore, by driving the pair of hydraulic cylinders 46A and 46B and extending and contracting the rods thereof, the main body frames 30A and 30B are connected to the support members 28A and 28B.
It rotates around B.

Here, the cleaning liquid supply pipes 18A, 18A,
8B is connected to the main body frames 30A and 30B via the nut members 36A and 36B, so that the main frames 30A and 30B rotate to rotate in conjunction therewith. Thus, the cleaning liquid supply pipe 18
A and 18B drive the motor 40,
Reciprocating along the axis, the hydraulic cylinders 46A, 46A
It rotates by driving B.

Since the nozzles 20A and 20B are provided in the cleaning liquid supply pipes 18A and 18B, the nozzles 20A and 20B reciprocate as the cleaning liquid supply pipes 18A and 18B reciprocate, and rotate (up and down). Swinging in the direction). As described above, when the nozzles 20A and 20B slide horizontally and swing vertically, the cleaning liquid ejected from the nozzles 20A and 20B also slide horizontally and swing vertically. For this reason, there is a possibility that the sprayed cleaning liquid may be scattered around. In order to prevent the washing liquid from scattering around, a lid 50 as described below is provided.

As shown in FIG. 4 and FIG.
Is formed in a rectangular shape so as to cover the frame 16, and a pair of rotating shafts 50A, 50A are fixed to the base end thereof. The rotating shafts 50A, 50A are rotatably supported by bearings 52, 52 provided on the frame 16,
A rotary cylinder 54 is connected to one of the rotation shafts 50A (the right side in FIG. 4). The lid 50 swings around the rotation shafts 50A and 50A by driving the rotary cylinder 54, whereby the lid 50 opens and closes the upper opening of the cleaning tank 14.

Incidentally, as shown in FIG.
When the lid 50 is closed, a predetermined gap is formed at both ends of the upper end of the lifter 60.
Are the gaps through which the work holding portions 74, 74 pass. Therefore, the width of the lid 50 is determined by the work holding portion 74,
74 are formed smaller than the interval. With the above configuration,
The cleaning liquid sprayed from the nozzles 20A and 20B can be prevented from scattering into the cleaning tank 14. On the other hand, the cleaning liquid sprayed into the cleaning tank 14 hits the wafer W accommodated in the cleaning tank 14 and cleans the wafer W. However, the cleaning liquid after cleaning the wafer W is applied to the cleaning tank 14 by its own weight. Fall into. Then, the cleaning liquid that has fallen into the cleaning tank 14 is formed into a tapered cleaning tank 14.
Are collected at the center at the bottom surfaces 14A, 14A of the cleaning tank 14, and then discharged to the outside through a discharge port 56 formed at the side surface of the cleaning tank 14.

Incidentally, as shown in FIG.
Is provided with a solenoid valve 58. By driving the electromagnetic valve 58 to close the discharge port 56, the cleaning liquid ejected from the nozzles 20A and 20B cannot be discharged. As a result, the cleaning liquid is stored in the cleaning tank 14. It becomes possible. The cleaning device body 12
Is configured as described above, and then the cleaning device main body 1
The configuration of the lifter 60 for transferring the wafer W into and out of the wafer 2 will be described.

As shown in FIG. 1 and FIG.
In the vicinity of 4, a column 62 is erected vertically. A pair of guide rails 64, 6
4 are laid, and on the guide rails 64, 64,
An elevating base 68 is slidably supported via sliders 66,66. In the vicinity of the column 62,
An elevating cylinder 70 is provided in parallel with the column 62. The rod end of the elevating cylinder 70 is connected to a connecting member 68A provided at the upper end of the elevating base 68. Therefore, by driving the lift cylinder 70, the lift base 68 moves up and down along the guide rails 64.

The lifting base 68 has a pair of arms 7.
2, 72 are fixed horizontally. This pair of arms 7
Work holders 74, 74 formed in an L-shape are fixed to the distal ends of the workpiece holders 2 and 72.
74 is located above the cleaning tank 14. The wafer W is held by the work holding units 74 and 74 and is carried in and out of the cleaning tank 14.
It is performed as follows.

When cutting the ingot with a wire saw, the slice base S is adhered to the ingot to prevent the end of the ingot from being cut. A work block for mounting the ingot on the wire saw is bonded to the slice base S. For this reason, the wafer to be cut is cut while being bonded to the slice base S, and is carried out of the wire saw while being bonded to the work block.

The wafer cleaning apparatus 10 of the present embodiment also cleans the wafer W in a state where the wafer W is adhered to the work block B. For this reason, the holding of the wafer W is also performed via the work block B. Here, as shown in FIG. 5, grooves 74A, 74A for holding the work blocks B are formed in the work holding portions 74, 74, and the work blocks B are formed in the grooves 74A, 74A. By fitting both ends of the work block B,
Are held by the work holding portions 74, 74.

The lifter 60 is constructed as described above, and the lifting base 68 on which the wafer W is mounted is moved up and down by the lifting cylinder 70 to carry the wafer W into and out of the cleaning tank 14. Is performed. Note that the wafer W carried into the cleaning tank 14 by the lifter 60 is moved along the longitudinal direction of the cleaning tank 14.
4 is carried in. Therefore, the direction of the axis of the wafer W carried into the cleaning tank 14 is
The direction coincides with the direction of the axis of the cleaning liquid supply pipes 18A and 18B disposed in the inside.

The operation of the embodiment of the wafer cleaning apparatus according to the present invention configured as described above is as follows. First, after the completion of the cutting by the wire saw, the wafer W cut by the wire saw is taken out of the wire saw and transferred to the wafer cleaning device 10 by a transfer device (not shown). Then, the wafer W is mounted on the lifter 60. That is, the work block B to which the wafer W is bonded is held by the work holding portions 74 of the lifter 60. After mounting the wafer W on the lifter 60, the wafer cleaning apparatus 10 is operated.

At this time, the lifting base 68 of the lifter 60 is located at the uppermost position, and
Is in an open state. Further, the nozzles 20A and 20B disposed in the cleaning tank 14 are in a state where their injection ports are directed vertically downward as shown by the two-dot broken lines in FIG. When the wafer cleaning apparatus 10 is operated, first, the lifting cylinder 70 is driven, and the lifting base 68 is lowered toward the cleaning tank 14. The lowering of the elevating base 68 lowers the wafer 68 at the same time, whereby the wafer W is stored in the cleaning tank 14.

Then, the wafer W is placed in the cleaning tank 1.
4. When the cylinder 7 is lowered to a predetermined position,
0 is stopped, and the wafer W stops at that position. As a result, the wafer W is stored at a predetermined position in the cleaning tank 14. When the driving of the lifting cylinder 70 is stopped, the rotary cylinder 54 is driven, and the lid 50 is closed in the cleaning tank 14. Since the width of the lid 50 is formed smaller than the interval between the work holding parts 74, 74, the lid 50 does not hit the work holding parts 74, 74 even when the lid 50 is closed.

When the lid 50 has been closed in the cleaning tank 14,
Next, the hydraulic cylinders 46A and 46B for swinging the nozzles 20A and 20B are driven, and the nozzles 20A and 20B
It moves from the position of the two-dot broken line shown in FIG. 5 to the position of the solid line. The positions of the nozzles 20A and 20B shown by the solid lines are set such that when the cleaning liquid is jetted from the nozzles 20A and 20B, the jetted cleaning liquid hits the bonding portion between the wafer W and the slice base S. Have been.

When the wafer W is loaded, the nozzles 20A and 20B are retracted to the positions indicated by the two-dot broken lines in FIG. This is so as not to come into contact with 20A and 20B. As shown in FIG.
When the position is moved to the position shown by the solid line, the cleaning is started.
That is, the cleaning liquid is supplied from a cleaning liquid supply device (not shown) to the cleaning liquid supply pipes 18A and 18B, and the cleaning liquid supplied to the cleaning liquid supply pipes 18A and 18B is jetted from the nozzles 20A and 20B.

The wafer W accommodated in the cleaning tank 14
Is shower-cleaned by the cleaning liquid jetted from the nozzles 20A and 20B. At the time of the shower cleaning, the nozzles 20A and 20B are driven as follows. That is, since the nozzles 20A and 20B can apply the cleaning liquid to only one place in the stopped state,
Insufficient cleaning. Therefore, the drive units 26A and 26B are driven by the motor 40, and the nozzles 20A and 20B are reciprocated along the axis of the wafer W.

As a result, the cleaning liquid uniformly hits the entire wafer W on the wafer W accommodated in the cleaning tank 14, so that no cleaning residue is generated. The nozzle 20
The cleaning liquid sprayed from A and 20B effectively enters the gap between the wafers W, and the inside thereof can be sufficiently cleaned by the water pressure.

The shower cleaning by the nozzles 20A and 20B is continuously performed for a certain period of time. After a predetermined period of time, the supply of the cleaning liquid is stopped and the operation is completed. The cleaning liquid sprayed at the time of this cleaning is collected at the bottom in the cleaning tank 14 and then discharged to the outside through the discharge port 56. When the shower cleaning is completed, the hydraulic cylinders 46A and 46B for swinging the nozzles 20A and 20B are driven, and
0A and 20B move from the position shown by the solid line to the position shown by the two-dot broken line in FIG. At the same time, the rotary cylinder 54 is driven, and the lid 50 is opened from the cleaning tank 14.

When the lid 50 is opened, the lifting cylinder 70 is driven, the lifting base 68 is raised, and the cleaned wafer W is carried out from the cleaning tank 14. In the above series of steps, the cleaning by the wafer cleaning apparatus 10 is completed, and the wafer W is removed from the work holding units 74, 74. Then, when there is a wafer W to be cleaned next, the cleaning operation is performed in a similar process.

As described above, according to the wafer cleaning apparatus 10 of the present embodiment, the wafer W is cleaned by the cleaning liquid sprayed from the nozzles 20A and 20B.
Cleaning up to the gap between the wafer and the wafer W. Further, since there is only one cleaning tank 14, the apparatus itself can be made compact as compared with the conventional cleaning apparatus.

It should be noted that more effective cleaning of the wafer W can be performed by employing the following cleaning method. That is, in the above-described embodiment, the nozzles 20A and 20B only reciprocate along the axis of the wafer W during shower cleaning. However, the nozzles 20A and 20B can be swung up and down by driving the hydraulic cylinders 46A and 46B. Using this, at the time of the shower cleaning,
The cleaning liquid is jetted while not only reciprocating the nozzles 20A and 20B along the axis of the wafer W but also swinging the nozzle 20A in the vertical direction.

As a result, the cleaning liquid is uniformly supplied to the wafer W as a whole, and the wafer W can be cleaned more effectively. The nozzles 20A, 20B
Swing of the nozzles 20A, 20B as in the above-described example.
May be performed in combination with the horizontal slide, or may be performed alone.

Further, one cycle may be constituted in the order of horizontal slide → vertical swing → combination of horizontal slide and vertical swing, and this cycle may be repeated. Moreover, in the wafer cleaning apparatus 10 of the present embodiment, the cleaning liquid can be stored in the cleaning tank 14 by closing the electromagnetic valve 58, so that the following cleaning method can be performed.

That is, after the shower cleaning described in the above embodiment, all the cleaning liquid supplied at the time of the shower cleaning is discharged from the cleaning tank 14 and the electromagnetic valve 58 is closed. Then, the cleaning liquid is injected again from the nozzles 20A and 20B, and the injected cleaning liquid is stored in the cleaning tank 14. When the cleaning liquid has accumulated to a predetermined water level (to the extent that the entire wafer is immersed), the injection of the cleaning liquid is stopped. Then, the lifting / lowering cylinder 70 is driven to move the wafer W up and down in the cleaning liquid. That is, rocking cleaning is performed.

As a result, dirt accumulated between the wafers W can be effectively washed away.
This oscillating cleaning is performed continuously for a certain period of time, and after a lapse of a predetermined period of time, the driving of the lifting cylinder 70 is stopped,
Open and drain. As described above, by combining the swing cleaning with the shower cleaning described in the above embodiment, more effective wafer cleaning can be performed.

Further, by performing shower cleaning once more after the swing cleaning, more complete cleaning of the wafer can be performed. Although not shown, an ultrasonic oscillation device may be provided around the cleaning tank 14 to perform ultrasonic cleaning by oscillating ultrasonic waves from the ultrasonic oscillation device during the swing cleaning. Thereby, the cleaning effect is further improved.

This ultrasonic cleaning may be used together with the above-mentioned rocking cleaning, or may be performed alone.

[0047]

Kwai according to the present invention, as described above, according to the present invention
According to the cleaning device, a plurality of nozzles disposed in the cleaning tank
Is driven by the reciprocating drive means and travels in the axial direction of the wafer.
Going back and spraying the cleaning solution over the entire wafer
After spray cleaning of the cleaning liquid, the cleaning liquid is
And move the wafer up and down to remove the wafer.
Cleaning allows effective cleaning of wafers
You.

[Brief description of the drawings]

FIG. 1 is a front view showing an overall configuration of a wafer cleaning apparatus according to the present invention.

FIG. 2 is a side view showing the overall configuration of the wafer cleaning apparatus according to the present invention.

FIG. 3 is a front view of the cleaning device main body.

FIG. 4 is a plan view of a cleaning device main body.

FIG. 5 is a sectional view taken along line AA of FIG. 4;

FIG. 6 is a sectional view taken along line BB of FIG. 4;

FIG. 7 is an enlarged view of a main part showing a configuration of a drive unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Wafer cleaning apparatus 12 ... Cleaning apparatus main body 14 ... Cleaning tank 16 ... Frame body 18A, 18B ... Cleaning liquid supply pipe 20A, 20B ... Nozzle 26A, 26B ... Drive unit 50 ... Lid 56 ... Drain port 58 ... Solenoid valve 60 ... Lifter 68 ... Elevating base 70 ... Elevating cylinder 74 ... Work holding part B ... Work block W ... Wafer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01L 21/304 B08B 3/02 B08B 3/12

Claims (3)

(57) [Claims] 1. A wafer cleaning apparatus for cleaning a wafer cut with a wire saw and having one end thereof adhered to a slice base, comprising: a cleaning tank in which the wafer is housed and capable of storing and draining a cleaning liquid; A support member that is provided to be vertically movable with respect to the cleaning tank and supports a wafer housed in the cleaning tank; a vertical driving unit that moves the support member up and down; a wafer housed in the cleaning tank A nozzle that is movably supported along the axial direction of the nozzle and ejects a cleaning liquid toward a wafer housed in the cleaning tank; and a reciprocating drive unit that reciprocates the nozzle. While cleaning the wafer by spraying the cleaning liquid toward the wafer housed in the cleaning tank while cleaning, The wash was in a cleaning tank, a wafer cleaning apparatus characterized by cleaning the wafer by vertically moving the wafer. 2. The wafer cleaning apparatus according to claim 1, wherein said nozzle is swingably supported in a vertical direction, and swing driving means for swinging said nozzle is provided. 3. A wafer cleaning apparatus according to claim 1, characterized in that a ultrasonic oscillator device to the cleaning tank.