JPH0559837U - Heat treatment equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] The processing gas on the surface is designed to prevent deformation of the plate-like body by supporting the peripheral edge of the plate-like body for forming a film for LSI or liquid crystal and prevention of uneven heat treatment of the plate-like body. Of the back plate of the upper plate to prevent the deposits formed on the back surface of the plate located in the upper stage from falling onto the plate in the lower stage. The purpose is to eliminate. [Structure] It is characterized in that lid-like holding bases on the upper surface of which the plate-shaped bodies can be mounted are vertically stacked so that they can be fitted together.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a plate-shaped heat treatment apparatus for forming a film for an LSI or a liquid crystal, and more particularly to a heat treatment apparatus configured such that the plate-shaped bodies can be vertically stacked.

[0002]

[Prior Art]

 A vertical heat treatment apparatus has been widely used for heat treatment of a plurality of plate-shaped bodies, for example, LSI wafers. That is, in the vertical heat treatment apparatus, the longitudinal axis of the heat treatment tube is arranged to extend in the vertical direction, and a plurality of semiconductor wafers are housed in the heat treatment tube by a holder, while flowing a predetermined gas between the semiconductor wafers. The heat treatment is performed by heating to a temperature of 600 to 1200 ° C. by a heating source such as an electric furnace arranged outside the heat treatment tube or an infrared ray lamp. With such a vertical heat treatment apparatus, it is possible to suppress the generation of particles or dust due to the sliding of the heat treatment tube and the holder or the boat, as compared with the conventional horizontal heat treatment apparatus, and further, space saving. Etc., and has many advantages.

However, when the heat treatment tube is stretched in order to increase the number of wafers to be processed due to the demand for mass production, there arises a problem that the temperature distribution in the longitudinal axis direction and the processing gas concentration distribution are likely to be non-uniform. Therefore, for example, in Japanese Patent Application Laid-Open No. 60-153116, a plurality of wafers 52 are horizontally mounted in a heat treatment chamber 56 in a heat treatment tube 51 on a support member 54, and the support member 54 is heated. A source 55 is rotatably hung, and a soaking tube 58 is interposed between the heat treatment tube 51 and the support member 54 to make the temperature distribution uniform, and the growth decreases as the wafer grows. A technology (hereinafter referred to as a first conventional technology) for uniforming the concentration distribution by controlling the supply pressure while considering the speed is disclosed (see FIG. 4).

Further, in the above-mentioned conventional technique, as shown in FIG. 5, the wafer 52 is placed on the support member 64 via the placing jig 65, and the wafer is turned on and off when the heating source 55 is turned on and off. A technique for preventing rapid heating and rapid cooling of the c (52) (hereinafter referred to as the second conventional technique) is also disclosed.

However, in the first prior art, since the wafer 52 is locked by the groove a formed in the support member 54, the gas treatment in the vicinity of the groove a is not performed as expected. However, in the worst case, it could not be used and led to a reduction in the part retention. In addition, in the first prior art, the supporting member 54 supports the peripheral edge of the wafer 52 at several places, and generally, in consideration of loading and unloading before and after the heat treatment, the supporting member 54 generally has a semicircular circumference. Since the wafer 52 was supported by the peripheral portion which was not present, the wafer 52 was deformed depending on the heat treatment process, and the reduction of the partial retention of the entire wafer was induced.

Returning to that, in the second prior art, the effect is not explicitly shown because the second prior art is mounted on the flat mounting jig 65, but the former first prior art does not. As a result, it is implied that the prevention of partial retention of the wafer 52 by the groove portion a 1 and the prevention of partial retention of the entire wafer 52 by deformation due to the support of several points on the peripheral edge are prevented.

[0007]

[Problems to be solved by the device]

 However, as the diameter of the member to be heat treated further increases in recent years, or depending on the material of the member to be heat treated, the problem of deformation due to the weight of the member to be heat treated under high temperature has become apparent. Further, in the above-mentioned first conventional technique, the deposits formed on the back surface of the upper wafer drop onto the upper surface of the lower wafer, which induces a serious defect called so-called back dope, which reduces the partial retention of the entire wafer. Let Further, in both the above-mentioned prior arts, the wafers are often arranged more densely than the limit, so that the processing gas does not flow uniformly on the wafer surface, which causes a so-called defect of the number of wafers. That is, when a support member in another heat treatment step which is formed so as to be densely arranged so as to increase the number of processed sheets is diverted and the difference in reaction conditions is not carefully considered, the above-mentioned number of failures is induced.

In view of the above-mentioned drawbacks of the prior art, the present invention aims to prevent the plate-like body from being deformed and the uneven heat treatment of the plate-like body by supporting the peripheral portion of the plate-like body for forming a film for LSI or liquid crystal. In addition, the flow of the processing gas on the surface is made uniform to eliminate the above-mentioned number of obstacles, and the deposit formed on the back surface of the plate located at the upper stage is allowed to fall on the plate at the lower stage. The purpose is to prevent the back dope and thereby eliminate the back dope.

[0009]

[Means for Solving the Problems]

 In order to solve such a technical problem, the present invention is characterized in that a lid-like holding base formed on the upper surface so that the plate-like body can be placed thereon is vertically stacked to be fittable. Further, the present invention is characterized in that the upper surface of the lid-shaped holding table is a closed surface. Further, the present invention is characterized in that a plurality of through holes are formed on the circumference / wall surface of the holding table. Further, the present invention is characterized in that the holding table located at the lowermost portion is formed of a heat shield that shields heat radiation in the soaking region.

The upper surface of the lid-shaped holding table does not necessarily have to be a closed surface, and may have a honeycomb-shaped hole. Further, in the lid-shaped holding bases stacked vertically, the size of the through-holes punched in the holding bases differs depending on the positions where the holding bases are stacked vertically, and are arranged, for example, in the lower layer. The case where the through hole of the holding base is larger than the through hole arranged in the upper layer is also included in the scope of the present invention. Further, the through holes are formed, for example, in a plurality of stages in the holding table, the through holes in the upper row are formed downward toward the inside of the support table, and the through holes in the lower row are formed downward toward the outside of the support table. It is within the scope of the present invention whether the through hole is inclined to which side. Further, the upper surface of the lid-shaped holding table on which the wafer is mounted is simply a flat surface, a concave surface conforming to the outer peripheral shape of the wafer, and the concave surface further dents the central portion so as to support only the peripheral edge portion of the wafer. Any shape such as a stepped concave surface is included in the scope of the present invention.

[0011]

[Action]

 According to such a technical means, by mounting the plate-shaped body on the upper surface of the lid-shaped holding base and stacking the lid-shaped support bases vertically, the plate-shaped body can be formed on the entire back surface or the back surface peripheral portion. Since it is supported, the plate can be prevented from being deformed by heat treatment. In addition, since the lid-shaped holding bases are stacked one above the other, the peripheral surface / wall surface of the holding bases plays the role of a buffer tube provided in the heat treatment chamber as a whole, and the thermal shock transmitted from the heating source to the reaction tube. It becomes possible to set a suitable heating environment for the plate-shaped body by alleviating the temperature distribution and leveling the uneven temperature distribution. Further, by mounting the plate-shaped body on the lid-shaped holding base, the plate-shaped body can be carried in and out of the heat treatment chamber via the lid-shaped holding base.

Further, according to the present invention, by making the upper surface of the lid-shaped holding base a closed surface, the plate-shaped body is supported by the entire back surface or the back surface peripheral portion, so that film formation is not possible on the back surface. In addition, since the plate-shaped body is housed in the lid-shaped holding table, the vapor deposition product of the plate-shaped body located in the upper layer does not fall onto the plate-shaped body in the lower layer, and the so-called bar is formed. The kuddo obstacle can be eliminated.

Further, according to the present invention, since the through hole is formed on the peripheral surface or the wall surface of the lid-shaped holding table, the processing gas can be uniformly introduced into and discharged from the lid-shaped holding table. It is possible to form a uniform film on the surface of the plate-shaped body. In addition, by changing the size of the through holes according to the position of the holding bases that are stacked one above the other, and by giving an inclination to the through holes that are drilled in multiple rows on one support base, The flow of the processing gas can be adjusted for each plate, and it is possible to form a uniform film while suppressing the intra-batch fluctuation between the plates and the fluctuation within each plate.

Further, according to the present invention, since the lowermost holding base is a heat shield in which, for example, quartz cotton or other heat insulating material is sealed, the heat in the heat treatment chamber is shielded so as not to be conducted or radiated to the base side. Heat becomes possible.

[0015]

【Example】

 Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of the components described in this embodiment are not intended to limit the scope of the present invention thereto, but are merely It's just an example.

FIG. 1 is an overall configuration diagram of a heat treatment apparatus according to an embodiment of the present invention. The heat treatment apparatus includes a disk-shaped base 11 and a gas introduction port 14 installed on the base 11 at the top end. A cylindrical bell-shaped reaction vessel 12, a plurality of infrared heaters 18 surrounded by the reaction vessel 12, a heat retaining tube 23 installed on the base 11, and a heat retaining tube 23 laminated on the heat retaining tube 23. It is composed of a plurality of lid-shaped holding bases 21 and a cap 22 placed on the uppermost layer of the holding bases 21, and all members except the infrared heater 18 are made of quartz glass material. ..

A processing gas discharge hole 15 is provided below the reaction vessel 12, and a suction pump (not shown) is connected to the downstream side of the processing gas discharge hole 15, so that the processing gas is introduced into the reaction chamber 13 through the gas inlet 14. The upper surface of the wafer 20 which is introduced and passes through a plurality of through holes 24 provided in the peripheral surfaces of the holding table 21 and the cap 22 and is placed on the upper surfaces of the holding table 21 and the heat insulating cylinder 23. After the contact, the exhaust pipe 15 can be exhausted.

The reaction container 12 is formed into a cylindrical bell shape by using a transparent quartz glass material that suppresses the absorption of infrared rays to a low level, and is formed into a pressure-proof seal on the opening side in contact with the base 11. The reaction chamber 13 is configured as a sealed space, and the reaction chamber 13 can be opened by using an elevating member (not shown).

2 (a), 2 (b) and 2 (c) are perspective views of a holder, a cap and a heat retaining tube according to an embodiment of the present invention, respectively. In order to obtain a uniform heating property, a semi-transparent quartz glass material containing air bubbles is used to form a cylindrical lid with an open lower end, and the peripheral surfaces of the holding table 21 and the cap 22 have a predetermined inclination angle and a large number of penetrations. The holes 24 are bored, and the processing gas is formed so as to be able to enter and be discharged into the holding table 21 and the cap 22 through the through holes 24. A sink corresponding to the outer diameter and the thickness of the wafer 20 is engraved on the closed surfaces of the upper surfaces of the holding table 21 and the heat insulating cylinder 23. When the wafer 20 is placed in the sink, the sink is easily formed. The upper surface of the wafer is formed so as to be in contact with the processing gas.

The heat retaining cylinder 23 is filled with quartz wool 26 and other heat insulating material so that heat in the reaction chamber 13 does not escape to the base 11 side. Further, a fitting groove 25 is fitted to the upper edge portions of the heat insulating cylinder 23 and the holding base 21, and a fitting groove 25 is fitted to the cap-shaped lower end portions of the cap 22 and the holding base 21 so as to fit with the fitting groove 25. A joint is provided, the holding table 21 is stacked and mounted on the heat insulating cylinder 23, and the cap 22 can be mounted on the uppermost layer.

3 (a), 3 (b) and 3 (c) are perspective views of a holding base, a cap and a heat insulating cylinder according to another embodiment of the present invention, respectively, the holding base 31, the cap 32 and the heat insulating cylinder. Reference numeral 33 denotes a member used for heat treatment of the glass substrate 30 in place of the wafer 20. Since the glass substrate 30 has a square shape, each of the members is also formed in a square shape, and the holding member 33 is provided. It corresponds to the table 21, the cap 22, and the heat insulating cylinder 23.

[0022]

[Effect of the device]

 As described above, according to the present invention, it is possible to prevent the plate-like body from being deformed by avoiding the point support of the peripheral part of the plate-like body on which the LSI or the liquid crystal film is formed and supporting it on the peripheral part or the entire surface. The heat treatment of the plate-shaped body can be made uniform, and further, the plate-shaped body can be carried in and out of the heat treatment chamber through the lid-shaped holding table. Further, it is possible to prevent the vapor deposition material formed on the back surface of the plate-shaped body located in the upper stage from dropping to the plate-shaped body in the lower stage, thereby eliminating the back dope. Further, by individually accommodating the plate-shaped bodies in the holding table, the flow of the processing gas on the surface can be made uniform, and thus the above-mentioned obstacle of the number of sheets can be eliminated. It has various remarkable effects.

[0023]

[Brief description of drawings]

FIG. 1 is an overall sectional view of a heat treatment apparatus according to an embodiment of the present invention.

2 (a), (b) and (c) are perspective views of a holder, a cap and a heat insulating tube according to an embodiment of the present invention.

3 (a), (b) and (c) are perspective views of a holder, a cap and a heat insulating cylinder according to another embodiment of the present invention.

FIG. 4 is an overall configuration diagram of a heat treatment apparatus according to a conventional technique.

FIG. 5 is a front view of another supporting member of the heat treatment apparatus according to the prior art.

[Explanation of symbols]

20 30 Plate-like body 21 31 Holding base 2
4 Through hole 23 33 Heat insulation tube

Claims (4)

[Scope of utility model registration request] 1. A heat treatment apparatus in which plate bodies for forming a film for an LSI or a liquid crystal can be stacked vertically, and a lid-like holding base on which a plate body can be mounted is stacked vertically. Heat treatment device characterized by being configured so that they can be fitted together 2. The heat treatment apparatus according to claim 1, wherein the upper surface of the holding table is a closed surface. 3. The heat treatment apparatus according to claim 1, wherein a plurality of through holes are formed on the circumference / wall surface of the holding table. 4. The heat treatment apparatus according to claim 1, wherein the holding table located at the bottom is formed of a heat shield that shields the heat radiation of the soaking region.