JPH03232228A - Liquid processor of semiconductor wafer - Google Patents

Abstract

PURPOSE:To avoid the occurrence of uneven processings, dust adherence etc., on the mirror surface by a method wherein processing liquid feeding pipes are provided on the lower part near the bottom surface of a liquid processing vessel for detachably retaining multiple semiconductor wafers in the erected state. CONSTITUTION:A retainer 2 wherein multiple wafers 1 are inserted is set in a washing up vessel 10 striding across the first liquid feeding pipe 11 so that cleaning up liquid 6 may be fed from the first and second liquid feeding pipes 11 and 12 as shown by arrows W1 and W2. The cleaning up liquid 6 is jetted from pores 11a to be lifted between respective wafers 1 as shown by the arrow W2 for cleaning up the surfaces of respective wafer 1. On the other hand, the cleaning up liquid fed from the pipe 12 is mixed with the cleaning up liquid 6 fed from the pipe 11 to be drained from a liquid drainage pipe 13 as shown by the other arrow W5. Respective wafers 1 retained by the retainer 2 are pressed down in the running direction as shown by the other arrow W4 so that the wafers 1 may be cleaned up in the oblique state almost the same direction within the allowable width range of the guide grooves 2e.

Description

[Detailed Description of the Invention] [Summary] Regarding a liquid processing device for semiconductor processing in the manufacturing process of semiconductor devices, it is possible to prevent the adhesion of processing liquid residue and dust to the wafer surface, especially the mirror surface side, during drying after processing. In order to prevent characteristic deterioration as a semiconductor device and improve productivity, a guide groove is formed on the inside that allows multiple semiconductor wafers to be removably placed in parallel while standing up. A semiconductor wafer holder through which a liquid can flow freely in the direction, and a semiconductor wafer holder with a semiconductor wafer mounted thereon such that a portion of each semiconductor wafer protrudes upward, the size of which is large enough to allow the semiconductor wafer holder to be immersed together with the semiconductor wafer. A liquid processing apparatus for semiconductor wafers comprising a liquid processing tank equipped with a liquid processing tank, wherein the liquid processing tank has a first liquid supply pipe for supplying the processing liquid at a lower part near the bottom, and a first liquid supply pipe near the liquid surface. At least a second liquid supply pipe is provided at the position for flowing the processing liquid in a direction substantially perpendicular to the surface of the semiconductor wafer.

[Industrial application field]

The present invention relates to a liquid processing apparatus for semiconductor wafers (hereinafter simply referred to as wafers) in the manufacturing process of semiconductor devices, and in particular, it eliminates the adhesion of processing liquid residue and dust to the wafer surface, especially the mirror surface side, during drying after processing. The present invention relates to a semiconductor wafer cleaning apparatus that prevents deterioration of characteristics of semiconductor devices and improves productivity.

In general, the manufacturing process for semiconductor device wafers requires multiple cleaning and film-forming processes, but as semiconductor devices become more highly integrated, wafers are required to have a high degree of cleanliness in each step. It has become so.

Therefore, in processing processes such as film formation using liquids and subsequent cleaning operations, it is necessary to completely remove the residue of the processing liquid and to ensure that uneven cleaning and dust adhesion are eliminated. If the drying process is started without being completely removed from the wafer due to surface tension, the residue of the processing liquid or cleaning liquid will cause uneven cleaning, dust adhesion, etc., which will cause defects in semiconductor devices and deteriorate their characteristics in subsequent processes. Measures against this problem are strongly desired.

[Prior Art] FIG. 3 is a diagram illustrating an example of a conventional liquid processing method for semiconductor wafers, in which (1) is a block diagram showing the entire apparatus, (2)
) is a view showing the main internal part of (1) taken along arrow a-a'', and (3) is a sectional view of the main internal part taken along arrow bb' of (1).

In addition, the case of the cleaning process will be explained in the figure.

Moreover, FIG. 4 is a diagram explaining the problem.

In FIG. 3, reference numeral 1 indicates a semiconductor wafer to be cleaned, for example, with a diameter of 6g>diameter and a thickness of about 0.5 mm.

Further, 2 in the figure represents a semiconductor wafer holder (hereinafter simply referred to as a holder).

The holder 2 in this case has a donkey shape in plan view, consisting of a longitudinal wall 2b having legs 2a protruding in the ridge direction at the four corners, and a wall 2c perpendicular to the wall 2b, with Between the walls 2c are two parallel wires 2 along the longitudinal direction.
d, and each of the inner wall surfaces 2b' facing the upper end surface portion of the beam 2d and the wall 2b along the longitudinal direction is provided with a plurality of wafers l standing parallel to the wall 2c at a predetermined interval ( Guide grooves 2e that can be inserted and held from above are provided in parallel at intervals of, for example, several square meters.

The fixing position of the beam 2d is set so that a part of the wafer 1 protrudes above the wall 2c to facilitate attachment and detachment of the wafer 1.

Further, in this case, the width of the guide groove 28 is usually 3 to 4 times the thickness of the wafer 1, for example, 1.5 to 2.0 m, in order to cope with warpage and bending of the wafer 1 during the processing process.
It is formed to about m.

Therefore, by inserting a plurality of wafers 1 from the upper part of the holder 2 along the answer guide groove 2e, the plurality of wafers 1 can be aligned substantially in parallel at regular intervals.

The cleaning tank 3 shown in the figure has a size sufficient to accommodate the holder 2 including the wafer 1 with the wafer 1 inserted therein. A liquid supply pipe 4 equipped with a plurality of holes 4a is attached to the holder 2.
A gutter 3a is formed around the upper opening, surrounding the upper opening.

Note that 5 connected to the gutter 3a is a drain pipe.

Here, as shown in the figure, the holder 2 into which the wafer 1 has been inserted is set in the cleaning tank 3 so as to straddle the liquid supply pipe 4 between the legs 2a, and the liquid supply pipe 4 is inserted into the holder 2. When the cleaning liquid 6 is supplied as shown in step 1, the cleaning liquid 6 is ejected from the hole 4a of the liquid supply pipe 4, hits the bottom of the cleaning tank 3, and then rises between each wafer 1 like a town, and flows through each wafer 1. The surface of wafer 1 is cleaned.

Note that the cleaning liquid 6 overflowing from around the upper opening of the cleaning tank 3 as shown in 1 flows into #113a and is then discharged from the drain pipe 5 as -4.

In this cleaning method, dust etc. adhering to the surface of each wafer 1 follows the flow of the cleaning liquid 6 and floats to the water surface, and then is discharged from the gutter 3a provided around the opening, resulting in efficient cleaning work. It can be carried out.

Therefore, when a predetermined cleaning operation is completed, the holder 2 can be pulled up from the cleaning tank 3, taken out and dried, and the required cleaning process can be completed.

FIG. 4, which shows the problem, shows the state when the wafer is dried after being taken out from the cleaning tank, and the wafer is enlarged in the figure for ease of understanding.

In the figure, 1 indicates a semiconductor wafer and 2 indicates a holder, which is the same as in FIG. 3.

When the wafers 1 that have been subjected to normal cleaning work are taken out from the cleaning tank together with the holder 2, each wafer 1 is placed in the guide groove 2 provided on the inner wall surface 2b' and the beam 2d of the holder 2, as shown in the figure.
It is stabilized in a state tilted in a random direction within the allowable range of the width of e.

In this case, when the holder 2 is taken out from the cleaning tank,
Due to its surface tension, a part of the cleaning liquid remains in small areas between the guide grooves 2e and the adjacent wafers 1, as shown in the illustrated dot areas p, -p7.

If the residual cleaning liquid is evaporated during the drying operation in this state, only the dust contained in each residual cleaning liquid will adhere to both surfaces of the wafer 1, resulting in uneven drying and dust adhesion.

In particular, the cleaning liquid remaining on the upper part of the wafer 1, as in the dot area 91 in the figure, hangs down due to its own weight, so a large amount remains, and the area that is contaminated by uneven drying, dust adhesion, etc. becomes large.

[Problems to be Solved by the Invention] In the conventional liquid processing method for wafers, when the holder is taken out from the processing tank for drying, there is a possibility that there is a Since a portion of the processing liquid remains between the wafers and the like, there has been a problem in that uneven drying and dust adhesion occur on both surfaces of the wafer at the end of the drying operation.

[Means to solve the problem]

The above-mentioned problem is solved by a semiconductor wafer holder, which has guide grooves formed on the inside that can be removably arranged in parallel with a plurality of semiconductor wafers in an upright state, and which allows liquid to freely flow through the inside at least in the vertical direction; A liquid processing apparatus for semiconductor wafers, comprising a liquid processing tank having a size sufficient to immerse the semiconductor wafer holder and the semiconductor wafer together with the semiconductor wafer holder so that a part of the wafer protrudes upward. Therefore, the liquid treatment tank is
A first liquid supply vibrator is provided at the lower part near the bottom surface for supplying the processing liquid, and a second liquid supply vibrator is provided at a position near the liquid surface to flow the processing liquid in a direction substantially perpendicular to the surface of the semiconductor wafer. The present invention is solved by a semiconductor wafer liquid processing apparatus equipped with a liquid supply vibrator.

[Function] A normal semiconductor wafer has one side as a pattern-forming surface, that is, a mirror surface.

In the present invention, the liquid processing apparatus is configured so that at least the residue of the processing liquid or the cleaning liquid does not remain on the mirror surface side of the wafer.

Therefore, processing unevenness, dust adhesion, etc. do not occur on the mirror surface side of the wafer, which is required, and processing with high productivity can be realized.

[Example] Fig. 1 is a configuration diagram illustrating a semiconductor wafer liquid processing apparatus according to the present invention, and Fig. 2 is a diagram showing a state during drying, but both of them are similar to Fig. 3 in the cleaning process. The case of is taken as an example.

In FIG. 1, the wafer 1 to be cleaned and the holder 2 are those described in FIG.

In addition, a cleaning tank (
The liquid processing tank 10 has a first liquid supply vibrator 11 equipped with a hole 11a similar to that shown in FIG. One side wall surface 1 at a position corresponding to the liquid supply vibrator 11 at a nearby position
A second liquid supply pipe 12 is disposed at 0a so that its tip slightly protrudes into the cleaning tank 10.
Further, a drain pipe 13 is provided near the upper liquid level of the wall surface 10b facing the wall surface 10a.

Here, as shown in the figure, the holder 2 into which a plurality of wafers 1 have been inserted is set in the cleaning tank 10 so as to straddle the first liquid supply pipe 11.
When the cleaning liquid 6 is supplied from the first and second liquid supply pipes 12 as indicated by -1 and -3, the cleaning liquid 6 supplied from the first liquid supply pipe 11 is ejected from the hole 11a as in the case of FIG. After hitting the bottom of the cleaning tank 10, it ascends between each wafer 1 as shown in -2 to clean the surface of each wafer 1.

On the other hand, the cleaning liquid 6 injected from the second liquid supply pipe 12 travels almost straight as shown, and together with the cleaning liquid 6 supplied from the first liquid supply pipe 11, it flows out from the drain pipe 13. He will be ejected as a fugitive.

In this case, each wafer 1 held in the holder 2 is pressed in the flow direction, that is, in the direction of W4, by the cleaning liquid 6 from the second liquid supply pipe 12 flowing near the upper part of the wafer 1. The guide grooves 2e are cleaned while being inclined in substantially the same direction within the permissible range of the width of the guide groove 2e.

Next, when the predetermined cleaning work is completed, the holder 2 is taken out from the cleaning tank 10, but in this case, each wafer 1 is washed by the cleaning liquid 6 from the second liquid supply pipe 12 until the wire holder 2 is lifted up. Since they are pressed in the same direction, they are in the same tilted state as above.

When the holder 2 is further lifted, the cleaning liquid 6 from the second liquid supply pipe 12 is divided into left and right sides by the wall 2c perpendicular to the longitudinal direction of the holder 2 explained in FIG. Each wafer 1 is taken out from the cleaning tank 10 as it is without pressing the wafer 1 .

Figure 2, which shows the dry state, represents such a state.
As shown in the figure, each wafer 1 is tilted in the same direction and stabilized within the allowable width of the guide groove 2e of the holder 2.

In case 2, when the wire holder 2 is taken out from the cleaning tank,
Since each wafer 1 is tilted substantially parallel to the same direction, a portion of the cleaning liquid remains only in a small portion of the gap between the wafer 1 and each guide groove 2e, as shown in the illustrated dot region P, ~pH.

Particularly in this case, the cleaning liquid 6 remains on only one surface, that is, the surface 1a.

Therefore, in order that the surface 1a on which the cleaning liquid 6 remains is the non-mirror side, in other words, the second liquid supply pipe 1 in FIG.
Each wafer l is placed so that the wall surface 10a side of 2 becomes the mirror surface 1b.
By inserting the wafer into the guide groove 2e of the holder 2, uneven drying, dust adhesion, etc. will not occur at least on the required mirror surface lb side of the wafer 1.

〔Effect of the invention〕

As described above, the present invention provides a semiconductor wafer which eliminates the adhesion of processing liquid residue and dust to the wafer surface, especially the mirror surface side, during drying after processing, thereby preventing deterioration of characteristics as a semiconductor device and improving productivity. A liquid handling device can be provided.

Although the present invention is explained using a cleaning liquid as the processing liquid, the same effect can be obtained even in the case of a processing step using a background liquid such as a developing/fixing processing liquid after exposure.

[Brief explanation of drawings]

Fig. 1 is a block diagram illustrating the liquid processing apparatus for semiconductor wafers according to the present invention, Fig. 2 is a diagram showing the state during drying, and Fig. 3 is an illustration of an example of a conventional liquid processing method for semiconductor wafers. Figure 4 is a diagram explaining the problem. In the figure, 1 is a semiconductor wafer, 1a is a surface, 1b is a mirror surface, 2 is a semiconductor wafer holder, 2c is a wall, 2e is a guide groove, 6 is a cleaning liquid, 10 is a cleaning tank (liquid processing tank), 10a and Job are 11 represents a wall surface, 11 represents a first liquid supply pipe, and 12 represents a second liquid supply pipe. 11a is a hole, 13 is a drain pipe, 1st part of the present invention: 1) Hand conductor wafer ozm processing and explanation T3 construction diagram Figure 2

Claims (1)

[Scope of Claims] A semiconductor wafer in which a guide groove (2e) is formed on the inside so that a plurality of semiconductor wafers (1) can be detachably arranged in parallel in an upright state, and a liquid can freely flow through the inside at least in the vertical direction. Holder (2) and each of the above semiconductor wafers (
The semiconductor wafer (1) is placed so that a part of the semiconductor wafer (1) protrudes upward.
) A liquid processing apparatus for semiconductor wafers comprising a liquid processing tank (10) having a size sufficient to immerse the semiconductor wafer holder (2) equipped with the semiconductor wafer (1) together with the semiconductor wafer (1), The liquid processing tank (10) is provided with a first liquid supply pipe (11) for supplying the processing liquid at a lower part near the bottom, and at a position near the liquid surface at least approximately on the surface of the semiconductor wafer (1). A liquid processing apparatus for semiconductor wafers, characterized in that a second liquid supply pipe (12) is provided for flowing the processing liquid in an orthogonal direction.