JPS59191327A - Heat-treatment jig - Google Patents

Abstract

PURPOSE:To improve heat-resistant characteristics and avoid the mingling of impurities and contaminants by a method wherein the surface of a main body, formed of heat-resistant material such as silicon, is covered with a silicon nitride film. CONSTITUTION:The surface of a main body 2, formed of heat-resistant material such as silicon, is covered with a silicon nitride film 10. The heat-resistant material is a sintered substance whose main component is polycrystalline silicon or silicon carbide. The silicon nitride film 10 is formed by CVD method or plasma method. With this constitution, even if the jig is used under the high temperature condition of higher than 1,100 deg.C, owing to its heat-resistant characteristics the heat deformation does not occur and it can hold wafers 9 firmly. Also the penetration of impurities and contaminants into the main body 2 is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a jig suitable for high temperature processing, and more particularly to a heat treatment jig suitable for use in high temperature processing in the manufacturing process of semiconductor devices.

[Background technology]

Heat treatment under high temperature conditions is considered essential in the manufacturing process of semiconductor devices. For example, in the process of diffusing impurities into a semiconductor substrate (wafer), the wafer is
It is necessary to maintain the temperature atmosphere for a long time at a temperature of 0.00 or higher.

Therefore, the jig for supporting the wafer must be able to withstand this high temperature.

Conventionally, quartz glass and silicon (Si) have been proposed as materials for this type of jig. However, quartz glass has 11
Under conditions of 001:l' or more, thermal deformation occurs in a short time, and this is mainly used for low-temperature heat treatment. On the other hand, silicon, especially polycrystalline silicon, is the most promising material because it does not undergo thermal deformation even at the above-mentioned temperatures, but since the material is porous, impurities and contaminants from the deposition process soak in, which can be absorbed into the wafer during wafer processing. may cause autodoping and contaminate the wafer. Therefore, it is difficult to use it in processes such as diffusion.

In addition, there may be a problem that it is brittle and easily chipped, requiring careful handling.[Object of the Invention] The object of the present invention is to prevent heat deformation even under high temperature conditions, and to prevent contamination of the processed material such as waeno. Without,
Another object of the present invention is to provide a heat treatment jig that is easy to handle.

Another object of the present invention is to provide a heat treatment jig suitable for simultaneously processing a plurality of wafers.

The above and other objects and novel features of the present invention include:
It will become clear from the description of this specification and the accompanying drawings.

[Summary of the invention]

A brief overview of typical inventions disclosed in this application is as follows.

In other words, by forming the jig main body from silicon or a silicon-based material and coating its surface with a silicon nitride film, the silicon or other material improves heat resistance, and the silicon nitride prevents impurities and This prevents contamination from being mixed in and further improves the strength, making it possible to obtain a jig that is easy to handle and has excellent heat resistance.

〔Example〕

1 to 3 show an embodiment of the present invention,
This is illustrated as a jig that can stand and support a plurality of ueno sheets in parallel. This jig 1 has a plate-like main body 2 having an arc-shaped cross section, which is obtained by cutting a part of a cylindrical member in the axial direction. This plate-like main body 2 is made of silicon, particularly polycrystalline silicon, which can withstand high temperatures of 1100 tZ' or more. This plate-like main body 2 has a punch hole 3 in the center, and a flat part 5 is formed by cutting the outer circumferential surface 4 approximately in the center to improve stability when placed. Ru.

Further, on the inner peripheral surface 6° 6 located on both sides of the punch hole 3, a plurality of way/accommodating grooves 7 are formed with an arcuate cross section along the inner peripheral surface. As shown in an enlarged view in FIG. 3, this wafer/accommodating groove 7 has a tapered portion 8 formed at its opening portion to facilitate insertion of the wafer 9 into the groove 7, which is indicated by a chain line in the same figure. There is.

Also, the width of this wafer storage groove 70 is set to be slightly larger than the thickness of the wafer.
A silicon nitride (SIllN4) film 10 is formed over the entire surface. This silicon nitride film 10 is made of, for example, C.
It is formed by growing silicon nitride on the surface of the plate-like body 2 using a VD method or a plasma method. In this case, when using the plasma method, the wafer
・Film formation can be easily performed by simply changing the susceptor of the device for forming a silicon nitride film to one that matches the shape of the jig. By forming this silicon nitride film 10, the wafer storage groove 7 has a groove width that matches the thickness of the wafer.

According to the above configuration, since the plate-like main body 2 of the jig 1 is made of silicon, it will not be thermally deformed due to its heat resistance even when used under high temperature conditions of 1100 t:' or more. Can hold Waeno 9 firmly. On the other hand, since the surface of the plate-shaped body 20 is coated with the silicon nitride film 10, the density and hardness of the silico/nitride prevent impurities and dirt from soaking into the silicon of the plate-shaped body. Now, the strength of jig 1 will be improved. As a result, even when the jig 1 is used for wafer diffusion processing, it is possible to prevent auto-doping of the wafer and perform high-purity diffusion, and to prevent chipping of the jig, making it extremely easy to handle. It can be done.

Incidentally, as the material of the plate-like main body 2, a sintered body of silicon carbide may be used instead of silicon. This material is mainly composed of silicon carbide (SiC) and is sintered with at least one of beryllium oxide and boron nitride in a few percent, and has extremely excellent mechanical strength. Although this sintered body also has high-temperature heat resistance, since it is porous, it is subject to contamination with impurities. Therefore, by covering it with a silicon nitride film, this problem can be eliminated.

〔effect〕

(11 Jig) Since the surface of the plate-shaped body made of silicon is coated with a silicon nitride film, in addition to the heat resistance of silicon, the denseness and hardness of silicon nitride prevent impurities from penetrating and chipping. This makes it possible to perform heat treatment without contamination even under high-temperature conditions with easy handling.

(2) Since the plate-shaped main body is formed of a sintered body whose main component is silicon carbide, the overall strength of the jig can be further improved by the strength of the main body itself.

(3) Since a silicon nitride film is formed on the surface of the plate-shaped main body made of silicon or the like by CVD or plasma method, it can be manufactured easily.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the above Examples and can be modified in various ways without departing from the gist thereof. Nor. For example, the shape and structure of the jig may be various shapes and structures other than those in the embodiments.

[Application field]

In the above explanation, the invention made by the present inventor was mainly applied to a jig for heat treatment of semiconductor wafers, which is the field of application in which the invention was made, but it is not limited thereto, and It can also be applied to jigs for heat treatment.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a jig according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line ■■ in FIG. 1, and FIG. 3 is a sectional view taken along the line II in FIG. DESCRIPTION OF SYMBOLS 1... Jig, 2... Plate-shaped main body (main body), 7... Wafer storage groove, 9... Wafer, 10... Silicon nitride film.

Claims (1)

[Claims] 1. A jig for supporting a workpiece to be processed at high temperature,
A heat treatment jig characterized in that the surface of the main body is made of a heat-resistant material such as silicone and is coated with a silicon nitride film. 2. The heat treatment jig according to claim 1, wherein the heat-resistant material is polycrystalline silicon. 3. The heat treatment jig according to claim 1, wherein the heat-resistant material is a sintered body containing silicon carbide as a main component. 4. The heat treatment jig according to any one of claims 1 to 3, wherein the silicon nitride film is formed by a CVD method or a plasma method.