JPS6155918A - Semiconductor manufacturing apparatus - Google Patents

Abstract

PURPOSE:To suppress liberation of impurities from a ceramics sintered member, by coating an Si2N4 or SiC film with a high purity on the surface of the ceramics sintered member. CONSTITUTION:A susceptor holder 5 is comprised of a base portion 5a over the surface of which a film 5b is coated. There base portion 5a has a principal element of powder ceramics consisting of sole material of Si3N4, SiC or AlN, or composite material of Si3N4 and Al2O2, and has a sintering assistant such as Y2O3, CeO2 Al2O2 or MgO added to be sintered and formed. After this sintered member is machined with polishing, over the entire surface an Si3N4 or SiC film 5b with a high purity is coated. Coating the film 5b can suppress liberation of impurities positively.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for processing a semiconductor substrate (hereinafter referred to as a sea urchin) in a high-temperature processing chamber such as a vapor phase growth device, a diffusion device, or a heat treatment device. The present invention relates to semiconductor manufacturing equipment.

[Technical background of the invention and its problems]

Conventionally, reaction tubes, bell jars, etc. that form the entire processing chamber of semiconductor manufacturing equipment as described above, as well as parts such as susceptor supports and boats located inside the processing chamber, have been made of quartz. Quartz has been used because it has excellent chemical resistance and heat resistance, but it has the disadvantage of low mechanical strength and easy breakage. As a material to replace this quartz, Si
, N 4 pieces 8iC, Aj+N single [I'm thinking of Si, N, and 1.0. Ceramic sintered bodies whose main component is a composite of These ceramic sintered bodies.

It has high chemical resistance, heat resistance, and mechanical strength.

This is because relatively complex shapes can be obtained by molding, and machining by polishing is also possible.

It is an excellent material. However, these sintered bodies
With current technology, Y, O,, CeO2, AJ20. ,
It is difficult to sinter unless a sintering aid such as MfO is added, and impurities such as Fe may be mixed in when the raw material powder of the ceramic, which consists of the main components mentioned above, is ground in a ball mill during the manufacturing process. Put it away. In this way, when ceramic sintered gold containing sintering aids and impurities is used for equipment components located in the processing chamber, such as susceptor supports and boats, the sintering aids and impurities are liberated. And sea urchin...
This can lead to problems such as the need to take into account the conditions of use and thoroughly heat-treat the sintering aid before use to remove the sintering aid.

[Purpose of the invention]

The present invention is applicable to the case where a ceramic sintered body as described above is used as a component of a device inside a processing chamber.

The purpose is to more reliably prevent the contamination of sea urchins as described above.

[Summary of the invention]

In the present invention, the surface of the ceramic sintered body as described above is entirely coated with a film of high purity 5I3N or SiC to suppress the release of impurities from the ceramic sintered body.

〔Example〕

An embodiment of the present invention will be described below with reference to the first factor and FIG. Figure 1 shows a vertical vapor phase growth apparatus, which is one type of semiconductor manufacturing equipment, where 1 indicates pace.

2 is a bell jar, which forms the entire sealed 't''Lfc processing chamber (hereinafter referred to as reaction chamber) 3. 4 is a pace 1
It is a hollow rotating shaft that extends into the reaction chamber 3 through the shaft, and is rotated by a motor (not shown) provided below. A susceptor support 5, which will be described later, is attached to the upper end of the rotating shaft 4, and a susceptor 6 is attached to this susceptor support 5.

The various gases required for the phase growth process are designed to emit gold.

It is a 9 fl RF coil and is supported by a coil support 11 via a bolt l Of. The RF coil 9 and coil support 11 are placed on the pace 1 and covered by a t-coil cover 12.

The susceptor support 5, as shown enlarged in FIG.
The entire surface of the base material portion 5a is coated with a film 5bt. This base material portion 5atl.

Single unit of Si, N, , SiC, AJN fc tr
y S i3N, and l, O.

The main component is powdered ceramics consisting of a composite of Y, 0. , CeO2, A7I, O, and sintering aids such as nM y O are added and machined by polishing, and the entire surface is coated with high-purity Si, N,
Or coated with SiC film 5bis.

The film 5b can be formed by the CVD method with extremely high purity, and a coating that is dense and has high adhesion strength to the base material portion 5a and does not peel off.

Next, the operation of this device will be explained. The susceptor 6 is heated by the RF coil 9, and the susceptor wafer 1 is placed on it.
3 is heated and a reactive gas is ejected from the gas nozzle 7) hole 8 to cause vapor phase growth on the surface of the wafer 13. At this time, the susceptor support 5 is also heated, and if the film 5b'l is not coated, the sintering aid and impurities in the susceptor support 5 will fly out and be liberated into the reaction chamber 3, mixing with the reaction gas. However, the film 5b as described above is doped with the vapor-phase grown layer and changes the characteristics such as resistivity of the vapor-phase grown layer.
By coating the susceptor support 5VC, the release of impurities as described above can be reliably suppressed, and problems caused by the use of the ceramic sintered body as described above can be prevented.

The above-mentioned embodiment shows an example in which the present invention is applied to the metal segment support 5, but the coil cover 12 is merely placed on the pace 1, and the inside thereof is completely isolated from the reaction chamber 3. If this is not the case and the coil support 11 is formed of a ceramic sintered body as described above, it is preferable that this coil support 11 is also entirely coated with a film similar to the film 5b. In addition, the susceptor support 5 and the coil support 11
When using itself as an electrical insulator, 5ick
It cannot be used because it has no insulating properties, and if this is necessary, another insulating material must be used.

It goes without saying that the present invention is not limited to vapor phase growth equipment, but can also be applied to various semiconductor manufacturing equipment that processes sea urchins in high-temperature processing chambers such as diffusion equipment and heat treatment equipment. .

〔Effect of the invention〕

As described above, according to the present invention, the dish-shaped 4
By using a ceramic sintered body, it is possible to increase the rigidity and mechanical precision of the device, making it easier to handle and manufacturing higher quality semiconductor devices.

〔experiment〕

The base material portion 5a of the susceptor support 5 shown in FIG. 2 is made of a ceramic sintered body having the composition shown in Table 1.

A film 5b of Si, N, α3m is formed on the surface by CVD method.
It was coated to a thickness of m.

Table 1 On the other hand, commonly used quartz support supports,
The film 5 is formed of a ceramic sintered body having the composition shown in Table 1.
When the resistivity values of the three materials were measured under the same conditions using a susegrator support without a bi layer and the resistivity values of the three materials were measured, it was found that the first Fi+, gΩ-0 by vapor phase growth, 2 for the second time
6Ω-cm.

The third time, the value increased as the number of cycles increased to 34Ω, but it was significantly lower than 2500-(2) in the case of quartz, indicating that doping with impurities had occurred, whereas the film 5b If you code it, you will get a value of 230Ω-cm, which is almost the same value as quartz.

In addition, when the film 5b is not provided, the specific resistance value increases as the cycles are repeated, and the reason is that the release of impurities from the ceramic sintered body is intense at first. This is thought to be because it decreases as it is stacked, and it is thought that it will stabilize at a certain value if heat treated in advance.

[Brief explanation of the drawing]

FIG. 1 is a schematic sectional view of a vertical vapor phase growth apparatus to which the present invention is applied, and FIG. 2 is an enlarged sectional view of a susegrator support. 1... Base, 2... Bell jar, 3... Reaction chamber,
4...Rotating shaft, 5...Susegator support, 5a...Base material portion, 5b...Membrane, 6...Susceptor, 7...Gas nozzle. 9...RF coil, +1...Coil support, 12...
・Coil cover, +3... wafer.

Claims (1)

[Scope of Claims] 1. In a semiconductor manufacturing apparatus having device components formed of a ceramic sintered body in a processing chamber, the surface of the ceramic sintered body is coated with a film of high purity Si_3N_4 or SiC. A semiconductor manufacturing device characterized by: 2. The semiconductor manufacturing apparatus according to claim 1, wherein the coating is formed by a CVD method.