JP6994242B2 - Semiconductor wafer processing equipment - Google Patents

Description

The present invention relates to a semiconductor wafer processing apparatus for surface-treating a semiconductor wafer, and more particularly to a semiconductor wafer processing apparatus for reducing processing unevenness on the surface of a semiconductor wafer.

The surface of a disk-shaped semiconductor wafer cut from an ingot is chemically treated in order to satisfy various conditions such as uniformity and flatness that enable the final placement process of semiconductor elements and the multi-layering process. Polished targetly and mechanically. Since the polishing process involves a process of removing minute irregularities chemically and mechanically, reaction products are inevitably formed on the wafer surface, and most of them stay as they are.

Leaving these reaction products as they are not only has a great effect on the subsequent processes, but also has a significant effect on the quality of the final product. Therefore, in order to avoid such a situation, it is necessary to provide a step of cleaning the wafer surface, and various semiconductor wafer processing devices for realizing this have been conventionally proposed.

For example, there is a semiconductor wafer cleaning device shown in Patent Document 1. This semiconductor wafer cleaning device cassettes a semiconductor wafer by providing a wafer rotating means for rotating the semiconductor wafer with respect to the cassette while the semiconductor wafer is set in a cassette submerged in the cleaning liquid of the cleaning liquid tank. It is a semiconductor wafer cleaning device that can immerse the entire surface of a semiconductor wafer in the cleaning liquid tank while it is set to.

Japanese Unexamined Patent Publication No. 2002-184737

However, the invention described in Patent Document 1 may damage the semiconductor wafer due to contact between the semiconductor wafer and the wafer rotating means when the semiconductor wafer is rotated while being moved up and down by the wafer rotating means. The cleaning liquid cannot flow in the gap of the support portion of the cassette that supports the peripheral edge portion of the semiconductor wafer, and the cleaning of the peripheral edge portion of the semiconductor wafer may be insufficient, resulting in uneven processing on the surface.

The present invention has been made in view of the above problems, and when the semiconductor wafer is subjected to processing such as cleaning, impurities are sufficiently removed so as not to leave processing unevenness on the peripheral portion of the semiconductor wafer. It is an object of the present invention to provide a semiconductor wafer processing apparatus capable of improving the uniformity of surface treatment of a semiconductor wafer.

In order to achieve the above object, the semiconductor wafer processing apparatus of the present invention vertically supports a processing tank containing a processing liquid and a plurality of peripheral portions of a substantially disk-shaped semiconductor wafer and immerses them in the processing tank. In a semiconductor wafer processing apparatus including a cassette, the semiconductor wafer processing apparatus has a support that supports the cassette in the processing tank, and a swing portion that swings the support in a circular motion in a forward view. The portions include a first swinging portion that swings the support in the left-right direction, a second swinging portion that swings the support in the vertical direction, and the first swinging portion and the second swinging portion. It is characterized by having a drive unit for driving the swing unit .

Further, the first swinging portion is characterized in that it is connected to the shaft provided by the second swinging portion so as to be movable left and right in the length direction of the shaft.

Further, the second rocking portion is characterized in that it is connected to a rail installed in the height direction of the outer wall of the processing tank so as to be movable in the vertical direction.

Further, by driving the drive unit, the first rocking portion moves in the left-right direction, and at the same time, the second swinging portion repeatedly moves in the vertical direction, so that the cassette is kept horizontal while being viewed forward. It is characterized in that the cassette is swung in the processing tank in a circular motion.

According to the present invention, when a semiconductor wafer is subjected to processing such as cleaning, development, and etching, the cassette body holding a plurality of semiconductor wafers is moved in a circular motion in the processing tank. The treatment liquid can uniformly treat the surface of the semiconductor wafer.

Further, in particular, the treatment liquid can be fluidly infiltrated into the gap of the groove portion that supports the peripheral edge portion of the semiconductor wafer in the cassette, so that the peripheral edge portion of the semiconductor wafer can be uniformly treated.

FIG. 1 is a side view showing the configuration of a wafer processing apparatus. FIG. 2 is a front view showing the configuration of the wafer processing apparatus. FIG. 3 is a perspective view showing the configuration of the cassette. FIG. 4A is a diagram showing the operation of the swing mechanism, and FIG. 4B is a diagram showing a swing state of the cassette. FIG. 5A is a diagram showing the operation of the swing mechanism, and FIG. 5B is a diagram showing a swing state of the cassette. FIG. 6A is a diagram showing the operation of the swing mechanism, and FIG. 6B is a diagram showing a swing state of the cassette.

Next, the etching apparatus according to this embodiment will be described with reference to the drawings.
1 is a side view showing the configuration of the wafer processing apparatus, FIG. 2 is a front view showing the configuration of the wafer processing apparatus, and FIG. 3 is a perspective view showing the configuration of the cassette.
As shown in FIGS. 1 and 2, the wafer processing apparatus 1 includes a processing tank 100, a swing mechanism 200, a drive motor 300, and a cassette 400. The treatment tank 100 is composed of an outer tank 101 and an inner tank 102, and the treatment liquid is housed in the inner tank 102, and the treatment liquid overflows and flows to the outer tank 101. .. Although not shown, the treatment tank 100 may have a mechanism for collecting the treatment liquid that has flowed to the outer tank 101.

A treatment liquid supply pipe 110 for supplying the treatment liquid extends from the vicinity of the front wall along the vicinity of the bottom of the inner tank 102, and supplies the treatment liquid from a portion arranged near the bottom. The treatment liquid supply pipe 110 supplies the treatment liquid from the treatment liquid tank (not shown) to the inner tank 102.

The volume of the treatment liquid supplied to the inner tank 102 maintains a constant liquid level during the treatment process, and the height is at least the capacity at which the silicon wafer W to be treated can be completely immersed in the solution. be. Further, as an example of the treatment liquid, there is an etching liquid for etching the silicon wafer W, and in the case of this etching liquid, a mixed aqueous solution of nitric acid and hydrofluoric acid is used.

The swing mechanism 200 includes a support 201, a cassette mounting table 202 supported by the support 201, a swing shaft 203 connected to the support 201, a first connecting portion 204, and a second connection. It is composed of a portion 205, a drive shaft 206, a transmission portion 207, a swing plate 208, and a rail body 209.

The support 201 is composed of a shaft mounting portion 201a and a downward extending portion 201b extending downward from one end of the shaft mounting portion 201a, and these are connected in series. The downward extending portion 201b is inserted into the inner tank 102, is arranged along the vicinity of the rear wall, and extends to the vicinity of the bottom of the inner tank 102 (near the upper side of the treatment liquid supply pipe 110).

The end of the cassette mounting table 202 is connected to the tip of the downward extending portion 201b. The cassette mounting table 202 is provided with an engaging portion 202a for engaging and fixing the cassette 400. By engaging the lower portion of the cassette 400 with the engaging portion 202a, the cassette 400 can be fixed to the cassette mounting table 202.

Further, the swing shaft 203 is connected to the other end of the shaft mounting portion 201a constituting the support 201 so as to extend downward. The swing shaft 203 is formed of a long member, and is provided so as to penetrate the swing shaft 203 in the width direction of the swing shaft 203. The shaft 203a is supported by a support portion 208b formed so as to rise from both ends of the swing plate 208.
Then, the swing shaft 203 can reciprocate in the length direction of the shaft 203a.

Further, the drive shaft 206 is connected to the lower part of the swing shaft 203 via the first and second connecting portions 204 and 205. The first connecting portion 204 connects the first swing shaft 203 and the second connecting portion 205 with a fixed shaft 204a, respectively. The swing shaft 203 is rotatably connected to the drive shaft 206 via the rotation shaft 205a.

The drive shaft 206 is rotatably connected to the transmission unit 207 and the rotation shaft 207a. Further, it is connected to the swing plate 208 via a fixed shaft 208c. The transmission unit 207 is rotatably connected to the output shaft 301 of the drive motor 300.

As described above, the swing plate 208 has a support portion 208b formed so as to rise from both ends, and the support portion 208b supports the shaft 203a penetrating the swing shaft 203. Further, the swing plate 208 has a fitting portion 208a, and the fitting portion 208a has a swing plate 208 in the height direction of the rail 209a of the rail body 209 installed on the outer wall of the outer tank 101. Fitted so that it can be moved.
Further, the swing plate 208 is connected to the drive shaft 206 by a fixed shaft 208c.

As shown in FIG. 3, the cassette 400 has a plurality of guide grooves 401 for leaning the silicon wafers W in parallel. The guide groove 401 is for holding the left and right end portions of the silicon wafer W while leaving a gap.

Next, the operation of the swing mechanism will be described.
4 (a) is a diagram showing the operation of the swing mechanism, FIG. 4 (b) is a diagram showing a swing state of the cassette, and FIG. 5 (a) is a diagram showing the swing state of the swing mechanism. 5 (b) is a diagram showing an operation, FIG. 5 (b) is a diagram showing a swinging state of the cassette, FIG. 6 (a) is a diagram showing the operation of the swing mechanism, and FIG. 6 (a). b) is a diagram showing a state in which the cassette swings.

As shown in FIG. 4A, when the drive motor 300 is operated, the output shaft 301 rotates clockwise when viewed from the front. The rotation of the output shaft 301 causes the transmission unit 207 to start rotating clockwise around the axis of the output shaft 301.

Due to the rotation of the transmission unit 207, the rotation shaft 207a portion connecting the drive shaft 206 and the transmission unit 207 rotates in a circular motion.

The drive shaft 206 is slightly lowered from the position of the dotted line in the lower right direction, and the swing plate 208 fixed to the drive shaft 206 and the fixed shaft 208c is lowered from the position of the dotted line.

Further, due to the operation of the drive shaft 206, the swing shaft 203 moves from the position of the dotted line in the length direction of the shaft 203 (to the left in the figure).

As shown in FIG. 4B, due to the operation of such a swing mechanism, the cassette mounting table 202 to which the cassette 400 is fixed moves diagonally to the left from the position shown by the dotted line.

Next, as shown in FIG. 5A, when the transmission unit 207 rotates due to the rotation of the output shaft 301, the movement locus of the rotation shaft 207a portion of the drive shaft 206 comes to the lowest position. By the operation of the drive shaft 206, the swing plate 208 is lowered from the position of the dotted line to the lowest position. Along with this, the swing shaft 203 moves in the length direction (right direction in the figure) of the shaft 203a.

By such an operation of the swing mechanism 200, as shown in FIG. 5B, the cassette mounting table 202 to which the cassette 400 is fixed moves diagonally downward to the right from the position indicated by the dotted line.

Next, as shown in FIG. 6A, the transmission unit 207 rotates around the axis of the output shaft due to the further rotation of the output shaft 301, and the rotation of the transmission unit 207 causes the drive shaft 206 to rotate from the position of the dotted line. The rotation axis 207a portion moves in the upper left direction. Along with this, the swing plate 208 moves upward from the position of the dotted line. Further, the swing shaft 203 moves from the position of the dotted line in the length direction of the shaft 203a (to the right in the figure).

By such an operation of the swing mechanism 200, as shown in FIG. 6B, the cassette mounting table 202 to which the cassette 400 is fixed moves diagonally upward to the left from the position indicated by the dotted line.

As described above, by the operation of the swing mechanism 200, the cassette mounting table 400 makes a circular motion while maintaining the horizontal position in the front view as shown in FIGS. 4 (b) to 6 (b). As a result, the cassette 400 fixed to the cassette mounting table 400 also performs a circular motion in the same manner. The processing liquid contained in the cassette 400 is circulated in the cassette 400 by the circular motion of the cassette 400, and the surface treatment of the silicon wafer W stored in the cassette 400 can be uniformly performed.

Further, by circulating the processing liquid in the cassette 400, the processing liquid enters the gap of the guide groove 401 holding the silicon wafer W, and the processing liquid can sufficiently contact the arc portion of the silicon wafer W, so that the processing unevenness is achieved. Can be eliminated.

1 Silicon wafer processing equipment 100 Processing tank 101 Outer tank 102 Inner tank 200 Swing mechanism 201 Support 201a Shaft mounting part 201b Down extension part 202 Cassette mounting base 202a Engagement part 203 Swing shaft (first swing part)
204 First connecting part 205 Second connecting part 206 Drive shaft 207 Transmission part 207a Rotating shaft 208 Swing plate (second swing part)
208a Fitting part 208b Support part 208c Fixed shaft 209 Rail body 209a Rail 300 Drive motor 301 Output shaft

Claims (4)

A treatment tank containing the treatment liquid and
In a semiconductor wafer processing apparatus including a cassette in which a plurality of substantially disk-shaped semiconductor wafer peripheral edges are vertically supported and immersed in the processing tank.
A support that supports the cassette in the processing tank and
It has a swinging portion that swings the support in a circular motion when viewed forward.
The swinging portion includes a first swinging portion that swings the support in the left-right direction, a second swinging portion that swings the support in the vertical direction, the first swinging portion, and the swinging portion. A semiconductor wafer processing apparatus comprising a driving unit for driving a second rocking unit . The first aspect of claim 1, wherein the first swinging portion is connected to a shaft included in the second swinging portion so as to be movable left and right in the length direction of the shaft. Semiconductor wafer processing equipment. According to claim 1 or 2, the second swinging portion is connected to a rail installed in the height direction of the outer wall of the processing tank so as to be movable in the vertical direction. The semiconductor wafer processing apparatus described. By driving the drive unit, the first rocking portion moves in the left-right direction, and at the same time, the second swinging portion repeatedly moves in the vertical direction, thereby forming a circle in front view while maintaining the level of the cassette. The semiconductor wafer processing apparatus according to any one of claims 1 to 3, wherein the cassette is swung in the processing tank as if drawn.

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