JPH0714809A - Wafer cleaning device and wafer cleaning method - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a semiconductor wafer cleaning technique for improving the cleaning effect of the peripheral portion of the wafer and the wafer supporting portion of the carrier jig. [Structure] A carrier jig 7 in which a wafer 10 is supported substantially horizontally by a supporting groove 7a is used as a cleaning tank 2 by using an oscillating device 11.
By tilting the inside of the wafer 10 from the support groove 7a
Remove and wash. [Effect] Since the wafer is separated from the supporting wafer supporting portion of the carrier jig, the peripheral portion of the wafer and the wafer supporting portion of the carrier jig are sufficiently in contact with the cleaning liquid, and the peripheral portion of the wafer and the wafer supporting portion of the carrier jig are in contact with each other. It is possible to remove the chemicals and foreign substances remaining in the product in a short time. Therefore, it is possible to reduce defects due to adhesion of foreign matters and improve the yield in the cleaning process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor device manufacturing technique, and is particularly effective when applied to a semiconductor wafer cleaning technique.

[0002]

2. Description of the Related Art In manufacturing a semiconductor device, a film forming process and a lithographic process are repeated. Between these steps, there is a wafer cleaning step in order to obtain a clean wafer surface necessary for the next step. Wafer cleaning equipment is used in the cleaning process. FIG. 5 shows a cleaning tank portion of a conventional wafer cleaning equipment. The wafer 30 housed in the carrier jig 29 is cleaned with a chemical solution such as hydrogen fluoride or ozone sulfuric acid, and then the wafer 30 is housed in the cleaning tank 16 for water cleaning together with the carrier jig 29. It 1 in the cleaning tank 16
The wafer 30 and carrier jig 29 are left to stand for 0 minute or more to wash away chemicals and the like.

Regarding the cleaning technology for semiconductor wafers,
For example, “Monthly Semiconductor Wor-ld” 1992 3
Monthly issue (Published by Press Journal), pages 106 to 15
P.7, or "LSI Process Engineering" (published by Ohmsha), pages 133 to 135, etc.

[0004]

Most conventional semiconductor wafer (hereinafter simply referred to as "wafer") cleaning methods move the wafer up and down together with the carrier jig in the cleaning tank, or leave it standing still. is there. In this case, since the wafer is in an upright state, the peripheral portion of the wafer remains in contact with the wafer supporting portion inside the carrier jig, for example, the supporting groove. Therefore, the foreign matter due to the removal of the support groove by the chemical solution or the wafer peripheral portion cannot be completely removed by the cleaning liquid, and remains on the wafer peripheral portion and the support groove supported by the support groove, which causes contamination of the foreign matter. ing.

Therefore, an object of the present invention is to provide a semiconductor wafer cleaning technique for improving the cleaning effect of the peripheral portion of the wafer and the wafer supporting portion of the carrier jig.

The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

[0007]

The outline of the representative one of the inventions disclosed in the present application will be briefly described as follows. That is, the carrier jig, in which the wafer is supported substantially horizontally by the wafer supporting portion, is tilted in the cleaning tank so that the wafer is detached from the wafer supporting portion for cleaning.

[0008]

According to the above means, since the wafer is separated from the wafer supporting portion of the carrier jig, the peripheral portion of the wafer and the wafer supporting portion of the carrier jig are in sufficient contact with the cleaning liquid, and the peripheral portion of the wafer and the carrier jig are in contact with each other. The residual chemicals and foreign matter adhered to the wafer supporting portion of 1 are removed in a short time.

[0009]

Embodiment 1 An embodiment of the present invention will be described below with reference to FIGS.

1 (a) and 1 (b) are views showing a cross section and an operation of the wafer cleaning apparatus of the present invention, and FIG. 2 is a plan view of the wafer cleaning apparatus. A washing water supply pipe 5 is connected to the washing tank 2 so that the washing water 6 overflows. The overflowed cleaning water 6 flows out to an overflow liquid receiving tank 3 provided outside the cleaning tank 2 and is drained through a cleaning water drain pipe 4. Inside the cleaning tank 2, a carrier jig support member 8 for mounting and fixing the carrier jig 7 containing the wafer 10 is provided. The carrier jig support member 8 has a fixing jig 9 having a supporting groove 9a so that the wafer 10 can be received from the carrier jig 7 from the side.
Is provided. When the carrier jig 7 is placed on the carrier jig support member 8, the wafer loading / unloading opening of the carrier jig 7 is opposed to the wafer loading / unloading opening of the fixing jig 9.
The wafer 10 moves to the opposing fixing jig 9, and the supporting groove 9a
Place it so that it is supported by. The carrier jig support member 8 includes a rocking device 11 installed below the overflow liquid receiving tank 3, a rod-shaped transmission member 13, and an eccentric cam 12.
And is configured to swing like a seesaw when cleaning a wafer. The transmission member 13 penetrates the bottoms of the cleaning tank 2 and the overflow liquid receiving tank 3 and is connected to the eccentric cam 12 of the rocking device 11. A bellows pipe 14 for sealing the wash water discharged from the through hole is attached to a lower portion of the through hole at the bottom of the washing tank 2, and the wash water discharged into the bellows pipe 14 is drained from the wash water distribution pipe 4. The eccentric cam 12 rotates to move the transmission member 13 up and down. Therefore, when the two transmission members 13 alternately move up and down, the carrier jig fixing member 8 connected thereto swings like a seesaw. In addition, the carrier jig 7,
Carrier jig support member 8, fixing jig 9, and transmission member 1
3 is made of, for example, a fluororesin or the like in order to prevent corrosion due to a chemical solution or cleaning water.

Next, a wafer cleaning method using the wafer cleaning apparatus 1 will be described. First, the carrier jig 7 in which the wafer 10 is accommodated is transferred from the chemical liquid tank (not shown) into the cleaning tank 2 in a state where the wafer 10 is parallel to the upper surface of the carrier jig support member 8 by the transfer means. The carrier jig supporting member 8 is placed and fixed. In that case, the carrier jig 7 has a wafer loading / unloading opening at the carrier jig support member 8
It is made to face the wafer loading / unloading opening of the fixing jig 9 provided on the. The wafer 10 is provided between the carrier jig 7 and the fixing jig 9.
Leave a small gap so that the peripheral edge of the water comes into contact with the washing water during movement. The carrier jig 7 can be supported, for example, by providing uneven portions on the carrier jig support member 8 and the carrier jig 7 and fitting them together. Next, the rocking | fluctuation apparatus 11 is operated and the left and right eccentric cams 12 are rotated so that they are displaced from each other by a half circumference. Eccentric cam 1
The rod-shaped transmission member 13 connected to 2 repeats vertical movement alternately, and the carrier jig support member 8 connected to the transmission member 13 swings like a seesaw. At this time, the carrier jig support member 8 is inclined, so that the wafer 10 supported by the support groove 7a of the carrier jig 7 is detached from the support groove 7a by its own weight and is transferred to the facing fixing jig 9. The movement and vice versa are repeated. By repeating these operations a plurality of times, the peripheral edge of the wafer 10 separates from the support groove 7a of the carrier jig 7 and comes into contact with the cleaning water, and the residual chemical liquid or foreign matter attached to the peripheral edge of the wafer 10 is removed. . Further, since the cleaning water also enters the support groove 7a, the chemical liquid and the foreign matter remaining in the support groove 7a are removed. As a result, the peripheral portion of the wafer 10 and the support groove 7a can be cleaned in a short time. After the seesaw-shaped swing of the carrier jig fixing member 8 is repeated a plurality of times, the carrier jig 7 in which the wafer 10 is housed is pulled up from the cleaning tank 2 by the transfer means, and the next cleaning tank, a drying device, or the like. Be transported to.

[0012]

[Embodiment 2] In the above embodiment, an example in which the swinging means is provided below the cleaning tank has been described, but in this embodiment, an example in which the swinging means is provided in the conveying means will be described with reference to FIG. . Cleaning tank 16, overflow liquid receiving tank 17, cleaning water drain pipe 1
8, the conventional washing water supply pipe 19 and the like are used. The transport means 25 is a swinging device 2 that can move up and down, and front and back and left and right.
6, a carrier jig support member 22 for mounting and fixing the carrier jig 24, and a transmission member 28 for connecting the cam 27 of the swinging means 26 and the carrier jig support member 22. The carrier jig support member 22 is provided with a fixing jig 23 having a supporting groove 23a, and the wafer loading / unloading port is laterally arranged so that the wafer 24 moving from the carrier jig 21 can be laterally received. It is facing. One end of the transmission member 28 is connected to the peripheral edge of the cam 27, and the other end is connected to the carrier jig support member 22. The transmission member 28 moves up and down as the cam 27 rotates. Therefore, 2
By alternately moving the book transmission member 28 up and down, the carrier jig support member 22 operates in a seesaw motion. The carrier jig 21, the carrier jig support member 22, the fixing jig 23, and the transmission member 28 are made of, for example, a fluororesin or the like in order to prevent corrosion due to a chemical solution or cleaning water.

Next, the cleaning method of this embodiment will be described. In this embodiment, before the carrier jig 21 containing the wafer 24 to be cleaned is placed in the cleaning tank 16, the wafer 24 is placed on the carrier jig support member 22 of the transfer means 25 and the upper surface of the carrier jig support member 22. Place and fix in a state parallel to. In this case, the wafer loading / unloading opening of the carrier jig 21 faces the wafer loading / unloading opening of the fixing jig 23.
After the carrier jig 21 is set, the carrier jig 21 is conveyed to above the cleaning tank 16 by the conveying means 25.
The carrier jig supporting member 2 is moved down together with the conveying means 25.
The carrier jig 21, the fixing jig 23, and the transmission member 28 fixed to 2 are put into the cleaning water 20 in the cleaning tank 16.
Next, the cam 27 of the swinging means 26 is rotated so that the transmission member 28 moves up and down alternately. As a result, the carrier jig support member 22 connected to the transmission member 28 swings like a seesaw. At this time, the wafer 24 in the carrier jig 21 is inclined by tilting the carrier jig support member 22.
Moves to the opposing fixing jig 23 while its peripheral portion separates from the support groove 21a and comes into contact with the cleaning water, and vice versa. As a result, it is possible to remove the residual chemical liquid or foreign matter attached to the peripheral portion of the wafer 24. Further, since the cleaning liquid also enters the support groove 21a, the support groove 2
Foreign substances can also be removed from the chemical liquid remaining in 1a. After the carrier jig supporting member 22 repeats the seesaw-like swinging a plurality of times, the carrier jig 21 containing the wafer 24 is pulled up from the cleaning tank 16 together with the carrier jig supporting member 22 by the transfer means 25. Next wash tank,
Alternatively, it is conveyed to a drying device or the like.

Next, the function and effect of the present invention will be described.

(1) Since the wafer is separated from the supporting groove of the carrier jig, the peripheral portion of the wafer and the inside of the supporting groove of the carrier jig are sufficiently brought into contact with the cleaning liquid, and the peripheral portion of the wafer and the carrier jig are quickly contacted. It is possible to remove the chemical liquid and foreign matter remaining inside the support groove.

(2) Since the wafer is moved in the cleaning liquid, friction occurs between the wafer surface and the cleaning liquid.
The wafer surface can be cleaned in a short time.

(3) Since the wafer is moved in the cleaning liquid in a direction nearly horizontal to the direction of gravity, the movement of the wafer is gentle. Therefore, the impact when the wafer comes into contact with the supporting groove is small, and the wafer is not likely to be cracked or chipped or the supporting groove is cut by the wafer. Therefore, it is possible to prevent the generation of foreign matter during wafer cleaning.

(4) Since not only the surface of the wafer but also the peripheral portion can be cleaned, defects due to foreign matter can be reduced and the yield is improved.

The invention made by the inventor of the present invention has been specifically described based on the embodiments, but the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. Needless to say. In the above embodiment, the wafer is reciprocally moved between the carrier jig and the fixing jig. However, for example, as shown in FIG. 4, instead of the combination of the carrier jig and the fixing jig as described above. ,
The wafer 32 may be cleaned therein by using a horizontally long carrier jig 31 in which the wafer can be moved by tilting. In this case, the carrier jig supporting member used in the above embodiment is not used, but the transmitting member 3 connected to the rocking device 33.
4 is directly connected to the carrier jig 31. Further, in the method of the above embodiment, the wafer is reciprocally moved only by the seesaw-like rocking, but when the wafer is rocked in the seesaw-like shape while being vertically moved, the pressure of the cleaning liquid is applied to the wafer along with the vertical movement. Since the friction with the cleaning liquid is increased, the cleaning effect is further enhanced.

In the above embodiment, the specific example of the present invention in the case of washing with water was explained, but the same effect can be obtained by using it for washing with a chemical solution.

[0021]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

That is, by tilting the carrier jig in which the wafer is supported substantially horizontally by the wafer supporting portion in the cleaning tank, the wafer is separated from the supporting wafer supporting portion of the carrier jig, so that the wafer peripheral portion and the wafer supporting portion are supported. The wafer supporting portion of the carrier jig is sufficiently brought into contact with the cleaning liquid, and the chemical liquid and foreign matter remaining on the peripheral portion of the wafer and the wafer supporting portion of the carrier jig can be removed in a short time. Therefore, it is possible to reduce defects due to adhesion of foreign matters and improve the yield in the cleaning process.

[0023]

[Brief description of drawings]

1A and 1B are a cross-sectional view and an operation diagram of a wafer cleaning apparatus that is an embodiment of the present invention.

FIG. 2 is a plan view of a wafer cleaning apparatus that is an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a wafer cleaning apparatus that is another embodiment of the present invention.

FIG. 4 is a cross-sectional view of a wafer cleaning apparatus that is another embodiment of the present invention.

FIG. 5 is a sectional view of a conventional wafer cleaning apparatus.

[Explanation of symbols]

1 ... Wafer cleaning device, 2 ... Cleaning tank, 3 ... Overflow liquid receiving tank, 4 ... Cleaning water distribution pipe, 5 ... Cleaning water supply pipe, 6 ... Cleaning water, 7 ... Carrier jig, 7a …… Support groove, 8 …… Carrier jig support member, 9 …… Fixing jig, 9
a ... Support groove, 10 ... Wafer, 11 ... Oscillating device, 1
2 ... Eccentric cam, 13 ... Transmission member, 14 ... Bellows tube,
15 ... Wafer cleaning device, 16 ... Cleaning tank, 17 ... Overflow liquid receiving tank, 18 ... Cleaning water distribution pipe, 19 ...
Cleaning water supply pipe, 20 ... Cleaning water, 21 ... Carrier jig, 21a ... Support groove, 22 ... Carrier jig support member, 23 ... Fixing jig, 23 ... Support groove, 24 ... Wafer , 25 ... Transporting means, 26 ... Oscillating device, 27 ... Cam, 28 ... Transmission member, 29 ... Carrier jig, 30 ...
... Wafer, 31 ... Carrier jig, 32 ... Wafer, 3
3 ... Oscillating device, 34 ... Transmission member

Claims (8)

[Claims] 1. A wafer cleaning apparatus having a cleaning tank for cleaning a wafer containing a cleaning liquid and having a peripheral edge portion supported in parallel to each other by a wafer supporting portion inside a carrier jig, together with the carrier jig. And a carrier jig supporting member for supporting the carrier jig supporting the wafer substantially horizontally in the cleaning liquid, and the carrier jig so that the peripheral edge portion of the wafer is separated from the wafer supporting portion. A wafer cleaning apparatus comprising: a swinging unit that tilts a support member. 2. The carrier jig supporting member is provided with a jig facing the carrier jig for receiving the wafer separated from the wafer supporting portion. 1. The wafer cleaning apparatus according to 1. 3. The swinging means swings the carrier jig supporting member in a seesaw shape.
Alternatively, the wafer cleaning apparatus according to item 2. 4. The swinging means is provided below the cleaning tank, and is connected to the carrier jig support member via a transmission member penetrating the bottom of the cleaning tank. The wafer cleaning apparatus according to claim 1, 2 or 3. 5. The wafer cleaning method according to claim 1, wherein the swinging means is integrally provided with a transfer means for transferring the carrier jig above the cleaning tank. apparatus. 6. A wafer cleaning method for cleaning a plurality of wafers, which are supported in parallel with each other by a wafer support section inside a carrier jig, in a cleaning tank together with the carrier jig, wherein the carrier cleaning is performed in the cleaning tank. A method for cleaning a wafer, wherein the wafer is detached from the wafer supporting portion and cleaned by inclining a tool. 7. The wafer cleaning method according to claim 4, wherein the wafer detached from the wafer supporting portion is returned to the wafer supporting portion by inclining the inclined carrier jig in the opposite direction. 8. The wafer cleaning method according to claim 4, wherein the carrier jig is tilted by using a swinging means.