JPH0645333U - Semiconductor wafer holding boat - Google Patents

Abstract

(57) [Abstract] [Purpose] A semiconductor holding boat for aligning and holding a large number of semiconductor wafers in a heat treatment apparatus has a contact portion with a support rod or the like for holding the wafer while ensuring a stable posture of the wafer. (EN) Provided is a semiconductor wafer holding boat in which the contact area is reduced and the product yield rate is improved. A semiconductor wafer holding boat having a supporting member having a holding groove for holding a peripheral edge of a semiconductor wafer by supporting a single or plural points, wherein the holding groove has a curvature shape at least the bottom of which follows the outer shape of the wafer, The wafer is formed into a fan shape with its apex connected inside.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a semiconductor storage jig for aligning and holding a large number of semiconductor wafers, and in particular, for mounting a semiconductor wafer and supporting a single or plural points of holding wafers through a holding groove, a film forming surface of a holding portion of the wafer is formed. The present invention relates to a semiconductor wafer holding boat that provides a suitable holding groove for a wafer supporting member that reduces defects.

[0002]

[Prior art]

 Conventionally, in a semiconductor manufacturing process, a semiconductor wafer (hereinafter referred to as “wafer”) is placed in a heating furnace surrounded by a heater, a predetermined gas is caused to flow, and impurities are permeated into the wafer in a predetermined high temperature atmosphere. Drive-in processing is performed. At this time, a semiconductor processing boat (hereinafter referred to as a boat) is used which holds a large number of wafers aligned and held. In this boat, a large number of wafers to be stored are treated as one unit, processed into pipes, plates and solid rods, and a holding groove that holds the peripheral edge of the wafer with single or multiple point support that can support the wafer. A supporting rod or a supporting member (hereinafter, referred to as a supporting rod) having the above is manufactured, and these are arranged by arranging the number of wafers to be stored. For boats, especially for the materials that come into contact with the wafer, heat-resistant quartz glass, silicon or their compounds, or heat-resistant ceramic materials that do not chemically react with the wafer are often used. The hardness is high and the wafer is easily damaged. The boat and support rod can form an effective film thickness on the wafer, so that the wafer can hold a large exposed area so that the processing area can be as wide as possible, that is, the effective product yield of the wafer can be increased. Is composed of. Because of its thin thickness, chips, cracks, and cracks are likely to occur on the periphery of the wafer, and the defects may progress until they change over time and are destroyed. In order to prevent the occurrence of a slip line and prevent the damage of the slip line, an improvement proposal for a holding groove such as a support rod of a boat (for example, Japanese Patent Application No. Sho 63-1111224) has been made. In those proposals, the holding groove is a V-shaped groove, a taper groove, a U-shaped groove or a deformed groove that fulfills a predetermined purpose, and a wafer is brought into contact with the bottom and side portions of these grooves to stabilize their postures. It is possible to maintain. At this time, make sure that the depth of the holding groove is not too shallow, and that there is too much play in the groove width, so that it leans against the adjacent wafers and that the adjacent wafers do not come into contact with each other at the top of the wafers that are lined up. In addition, the wafer can be held upright or in a fixed direction.

In general, the support bar and the like have a bottom portion having a curved shape along the outer shape of the wafer 1 so that the holding groove has a cross-sectional shape that conforms to the outer peripheral surface 1a of the wafer 1 having an arc shape as shown in FIG. Since the groove bottom 4 is configured and cut into the circular support rod 2 to form the holding groove 3, the outer circumference of the groove receiving outer portion 6 of the groove receiving portion 11 of the holding groove 3 that abuts the wafer 1. The shape is usually circular with little play. At this time, the groove receiving peripheral portion 12 of the portion of the wafer 1 held by the holding groove 3 toward the inside of the wafer 1 has a small contact area compared to the planar size of the wafer 1. Therefore, it is the part that is most susceptible to stress. Therefore, the groove receiving peripheral portion 12 is the weakest portion which is most liable to be damaged, and is also the defective portion where frequent defective growth of oxide film, film surface peeling phenomenon and the like occur.

[0004]

[Problems to be solved by the device]

 However, in a V-shaped groove or the like, since the wafer is held in a point contact state with the holding groove, a slip line is liable to occur, and the wafer comes into contact with the side portion of the groove to emphasize posture stability. In this case, the dead space tends to become large by being held by the groove depth and the size of the abutting area. The film formation unevenness occurs in the part, and during the heat treatment process, the wafer creates a wide range of non-uniform thermal history around the holding groove to be held, and is also generated due to the presence of fine particles. Due to the phenomenon of deposition of deposits on the wafer, it becomes difficult to remove the wafer that sticks to the support rods, and the film surface formed on the wafer becomes easy to peel off from the stuck part. I had a problem point. These problems have resulted in poor product yields.

In view of the above-mentioned drawbacks of the prior art, an object of the present invention is to fully consider the characteristics of the wafer heat treatment step and the structure of the boat, and to form a film surface at a contact portion between the wafer to be held and a support rod or the like. While maintaining the stable posture of the wafer while maintaining the safety of the wafer, the contact area of these wafers is made as small as possible, resulting in the improvement of the product yield rate. It is an object of the present invention to provide a semiconductor wafer holding boat designed.

[0006]

[Means for Solving the Problems]

 The present invention relates to a semiconductor wafer holding boat 10 having a supporting member 2 for forming a holding groove 3 for holding a peripheral edge 1a of the semiconductor wafer 1 by a single or plural points for holding the wafer 1. At least the bottom of the wafer has a curved shape along the outer shape of the wafer, and is formed in a substantially fan-like shape in which the apexes are connected to the inside of the wafer.

[0007]

[Action]

 According to such a technical means, unlike the conventional invention, the boundary area of the groove receiving peripheral portion on the side of the wafer to be held by the holding groove is not arcuate, but as shown in FIG. As a result, by making the boundary area linear without changing the wafer holding capacity of the holding groove without changing the peripheral length, it is possible to cause film formation defects due to the area difference between the arc shape and the linear shape. In addition to reducing the number of parts, it is possible to reduce the contact area of the wafer in the holding groove, and this reduction reduces the non-uniform portion of the thermal history of the peripheral portion of the wafer holding groove and the deposition site of impurities etc. It exerts a suitable action for wafer deposition maintenance.

[0008]

【Example】

 Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described in this embodiment are not intended to limit the scope of the present invention to them, unless otherwise specified. It is only an example. 1 and 3 illustrate a semiconductor wafer holding boat according to a first embodiment of the present invention. FIG. 1 is a cross-sectional view of an essential part of a round support rod, and FIG. 3 shows the action of the support rod. In a cross-sectional view of an essential part, four cross-section circular support rods 2 which are inserted and positioned at both ends (not shown) are cut into a portion facing the wafer 1 to a substantially central portion of the cross section. The holding groove 3 is provided with a plurality of cuts so that the wafer 1 can be arranged in a row in the axial direction of the support rod 2 and is appropriately separated, and the holding groove 3 has a cross-sectional shape of at least that. The bottom has a curved shape that conforms to the outer shape of the wafer 1 to form an arc, and the apex is connected to the inside of the wafer 1. The groove bottom 4 is capable of contacting the peripheral edge of the wafer 1. , So that the cross-sectional shape of the holding groove 3 as a whole forms a substantially fan shape. Along round side surface of the support rod 2 of the wafer 1 side, so as to form two flat side surfaces, it is machined, that make up the main part of the boat 10. The holding groove 3 holds the wafer 1 by the groove side portion 5. 2 illustrates a semiconductor wafer holding boat according to a second embodiment of the present invention. FIG. 2 is a cross-sectional view of an essential part of a square support rod, and the support rod 2 shown here has a square cross-section. The cross-sectional shape of the holding groove 3 is such that at least the bottom portion thereof has a curvature shape along the outer shape of the wafer 1, and a vertex is connected to the inside of the wafer 1, and the groove bottom portion of the holding groove 3 is formed along the diagonal line of the cross section. 4 is cut to form an arc. The formation of the support rods in the other portions is the same as that shown in FIG.

Next, the mounting or behavior of the device of the present invention will be described. The wafer 1 is sequentially inserted into the holding groove 3 of the support rod 2 and mounted by a manual transfer tool (not shown). The attitude holding of the wafer 1 is determined by two factors, that is, the length of the groove bottom 4 of the holding groove 3 for holding the wafer 1 and the insertion depth of the holding groove 3, and as a result, the wafer 1 is held. Can be stabilized. It is desirable that the above-mentioned two elements are satisfied and the contact area between the wafer 1 and the support bar 2 or the area of the groove receiving peripheral portion 12 in the periphery thereof is small. In the device of the present invention, the groove shape is Since the structure is substantially fan-shaped instead of the circular arc having the same diameter as that of the conventional support rod, the above requirements can be realized in the smallest area, and the mounting of the wafer 1 is completed. In addition, the defective portion in which the stress generated when the wafer 1 is held by the holding groove 3 and the non-deposition or vapor deposition can occur is the contact portion with the outer peripheral portion 6 of the holding groove 3. , In the groove receiving peripheral portion 12 on the wafer 1 side. According to the structure of the present invention having a wafer holding area by the above-mentioned configuration, the groove receiving peripheral portion 12 is the smallest, and as a result, the defective portion is the smallest, the occurrence of the slip line of the wafer 1 at the time of mounting and demounting the wafer is prevented. It contributes to the suppression and reduction of sticking accidents and film peeling accidents.

Further, the behavior is such that, when the flowing gas flow comes into contact with the wafer 1 held by the boat 10, the gas diffuses along the surface of the wafer 1 by means (not shown). When reaching the supporting member 2, a gas flow is disturbed around the supporting member 2, and a film surface having non-film-forming unevenness is formed at the disturbed portion. As long as the wafer 1 is held by the holding groove 3 by some means, it is inevitable to have the disordered portion. Reducing this disordered portion reduces the non-uniformity of the thermal history, thus enlarging the film-formation regular processing part other than the non-uniform part and improving the product yield. The shortest length of the groove outer peripheral portion 6 of the support rod 2 in the structure of the present invention contributes to the reduction of the cause of the behavior due to the turbulence of the gas flow.

[0011]

[Effect of device]

 As described above, according to the present invention, while holding the wafer, the depth of the groove in contact with the wafer is minimized while the cutting depth of the groove and the length of the groove bottom of the supporting member of the boat are properly ensured. In other words, while ensuring the wafer holding capacity of the boat, the problems caused by sticking accidents during wafer loading and unloading are reduced, the contact area is reduced, and the non-deposition during heat treatment is also performed. It is possible to provide a suitable holding groove for a semiconductor wafer support member, which is suitable for wafer film formation maintenance by reducing unevenness, uneven thermal history, and areas where impurities and other vapor deposition occur. It becomes possible to provide an improved semiconductor wafer holding boat according to the present invention, which is extremely effective, and its practical value is extremely large.

[Submission date] April 30, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

Further, the behavior is such that, when the flowing gas flow comes into contact with the wafer 1 held by the boat 10, the gas diffuses along the surface of the wafer 1 by means (not shown). When reaching the supporting member 2, a gas flow is disturbed around the supporting member 2, and a film surface having non-film-forming unevenness is formed at the disturbed portion. As long as the wafer 1 is held by the holding groove 3 by some means, it is inevitable to have the disordered portion. Reducing this disordered portion reduces the non-uniformity of the thermal history, thus enlarging the film formation regular processing portion other than the non-uniform portion and improving the product yield. The shortest length of the groove outer peripheral portion 6 of the support rod 2 in the structure of the present invention contributes to the reduction of the cause of the behavior due to the turbulence of the gas flow. When the depth of the groove bottom portion 4 of the holding groove 3 for holding the wafer 1 is made shallow, as shown in FIGS. 5 (A) and 5 (B), a fan-shaped shape for forming the holding groove 3 in proportion to this is formed. Wakashi Ku is it is possible to a triangular top shape (groove receiving portion 11) in small, thereby, it is possible to further reduce the area of the peripheral portion 12 receiving groove disturbance of gas flow occurs.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0011

[Correction method] Change

[Correction content]

[0011]

[Effect of device]

As described above, according to the present invention, while holding the wafer, the depth of the groove in contact with the wafer is minimized while the cutting depth of the groove and the length of the groove bottom of the supporting member of the boat are properly ensured. In other words, while ensuring the wafer holding capacity of the boat, the problems caused by sticking accidents during wafer loading and unloading are reduced, the contact area is reduced, and the non-deposition during heat treatment is also performed. It is possible to provide a suitable holding groove for a semiconductor wafer support member, which is suitable for wafer film formation maintenance, by reducing unevenness, uneven portion of heat history, and deposition site of impurities and the like. The fan-shaped or triangular apex shape (groove receiving portion) forming the holding groove can be made small, thereby further reducing the area of the groove receiving peripheral portion where turbulence of gas flow occurs, and the present invention The effect of can be improved. It becomes possible to provide an improved semiconductor wafer holding boat according to the present invention, which has various remarkable effects such as the above, and its practical value is extremely large.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a round support rod for explaining a semiconductor wafer holding boat according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a main portion of a square support rod for explaining a semiconductor wafer holding boat according to a second embodiment of the present invention.

FIG. 3 is a sectional view of an essential part showing the action of the support rod according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view of a main part showing an operation of a support rod of a conventional holding boat.

[Explanation of symbols]

 1: Wafer 1a: Wafer peripheral edge 2: Support member 3: Holding groove 4: Groove bottom part 5: Groove side part 6: Groove outer peripheral part 10: Boat 11: Groove receiving part 12: Groove receiving peripheral part

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[Procedure amendment]

[Submission date] April 30, 1993

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] Figure 5

[Correction method] Added

[Correction content]

5A and 5B are modification examples showing the shape of the holding groove in each of the first and second embodiments.

[Procedure amendment 4]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 5

[Correction method] Added

[Correction content]

[Figure 5]

Claims (1)

[Scope of utility model registration request] 1. A semiconductor wafer holding boat having a supporting member having a holding groove for holding a peripheral edge of a semiconductor wafer by supporting a single or a plurality of points, wherein the holding groove has a substantially fan-like shape with an apex connecting to the inside of the wafer. Alternatively, a semiconductor wafer holding boat characterized by being formed in a triangular shape.