JPH0568539B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a method for manufacturing a shroud used in an apparatus for manufacturing a film-like semiconductor containing Ga.

In this specification, the term "aluminum" includes not only pure aluminum but also aluminum alloys.

Conventional technology and its problems For example, MBE of semiconductor films containing Ga such as GaAs
When manufacturing with semiconductor manufacturing equipment such as equipment, film formation in an ultra-high vacuum is an essential condition in order to obtain higher performance. Therefore,
A shroud is used in the deposition chamber of the MBE equipment. A conventional shroud has a cylindrical shape made of a stainless steel plate, and a stainless steel tube is spirally wound around the outer peripheral surface of the shroud, and a cooling fluid such as liquid nitrogen flows through the tube. When forming the semiconductor film, first, the shroud is heated to 200 to 250°C to perform a baking treatment to remove moisture adsorbed on the surface of the shroud, and then a cooling fluid is poured into the stainless steel tube. The shroud is cooled by this cooling fluid, and the remaining gas in the evacuated film forming chamber is adsorbed on its surface to obtain an ultra-high vacuum.
However, in conventional shrouds, the cylinder body and tube are made of stainless steel, so they are heavy and
Moreover, there was a problem that the thermal conductivity was not sufficient. If the thermal conductivity is insufficient, it will take time for the entire shroud to be evenly heated during the above-mentioned baking process, and it will also take time for the surface of the shroud to cool down to a predetermined temperature when cooling fluid is flowed. There was a problem.

Therefore, it has been considered to make a shroud using aluminum, which is lighter in weight than stainless steel, has excellent thermal conductivity, and has a small surface gas release coefficient. The reality is that shrouds made of aluminum have not yet been realized because if they adhere, they will corrode and create through holes.

An object of the present invention is to provide a method for manufacturing a shroud for semiconductor manufacturing equipment that solves the above problems.

Means for Solving the Problems According to the method of manufacturing a shroud for semiconductor manufacturing equipment according to the present invention, after producing an aluminum shroud cylinder having a cooling fluid circulation portion on the peripheral wall, at least the inner surface of the inner and outer surfaces of the aluminum shroud body is fabricated. , is characterized by forming a film having corrosion resistance against gallium by an ion plating method.

In the above, the shroud cylindrical body may be one in which an aluminum cooling fluid distribution pipe is spirally wound and bonded to the outer peripheral surface of an aluminum cylinder, or a cooling fluid distribution tubular body such as a roll bond panel. There is one in which an aluminum plate-like body with a bulging part is formed into a cylindrical shape and the abutted parts are joined.

In addition, in the above, films having corrosion resistance against gallium include TiN, TiC, AlN,
Examples include AlC, Al ₂ O ₃ and the like. A film made of TiN and AlN is formed by ion plating using N ₂ gas as a reactive gas and Ti or Al as an evaporator. Films consisting of TiC and AlC are produced using acetylene as the reactive gas and Ti as the evaporated metal.
Alternatively, it is formed by performing ion plating using Al. A film made of Al ₂ O ₃ is formed by ion plating using an oxygen-containing gas as a reactive gas and Al as an evaporated metal. The thickness of such a film is preferably within the range of 1 to 20 μm. The reason is that when the film thickness is less than 1 μm,
The corrosion resistance of the film against Ga is not sufficient, and 20μ
If it exceeds m, the processing time required for ion plating may become longer, which may lead to higher costs, and the thermal cyclability may decrease, causing cracks in the film when heating and cooling are repeated.
This is because there is a risk that the film may peel off.
The film thickness is controlled by controlling the ion plating processing time, the flow rate and velocity of the reactive gas, the deposition rate, and the like.

Ion plating on at least the inner surface of the inner and outer surfaces of the shroud cylinder is performed by placing the cylinder in a processing tank and using it as a cathode.

Examples Examples of the present invention will be shown below along with comparative examples.

Example 1 First, a cylindrical body for a shroud having a cooling fluid circulation portion on the peripheral wall was made from an aluminum material. Next, after spatter cleaning this shroud cylinder, ion plating was performed using N ₂ gas as a reactive gas and Ti as an evaporative metal to form a film with a thickness of 5 μm on both the inside and outside of the main body and lid. A TiN film was formed. In the above, the pressure of N ₂ gas during ion plating was 1 torr, and the temperature of the main body and lid was 200°C. Then, Ga was applied to the inner surface of the shroud cylinder.
After depositing 1 g of Ga, a thermal cycle test of heating at 200°C for 24 hours and then cooling with liquid nitrogen for 30 minutes was repeated for 6 cycles to examine the corrosive properties of Ga. As a result of observing both the inner and outer surfaces of the cylinder, no corrosion by Ga was observed.

Example 2 As vaporized metal during ion plating
Except for using Al, an AlN film with a thickness of 10 μm was formed on both the inner and outer surfaces of the shroud cylinder in the same manner as in Example 1 above, and corrosion by Ga was also examined in the same manner as in Example 1 above. As a result, no corrosion by Ga was observed on both the inner and outer surfaces of the shroud cylinder.

Example 3 A film with a thickness of 10 μm was applied to both the inner and outer surfaces of the shroud cylinder in the same manner as in Example 1, except that acetylene was used as the reactive gas during ion plating.
A TiC film was formed, and in the same manner as in Example 1 above.
We investigated erosion caused by Ga. As a result, no corrosion by Ga was observed on both the inner and outer surfaces of the shroud cylinder.

Example 4 As vaporized metal during ion plating
Except for using Al, an AlC film with a thickness of 8 μm was formed on both the inner and outer surfaces of the shroud cylinder in the same manner as in Example 3 above, and its corrosion resistance was examined in the same manner as in Example 1 above. As a result, no corrosion by Ga was observed on both the inner and outer surfaces of the shroud cylinder.

Example 5 As an evaporated metal during ion blasting
An Al ₂ O ₃ film with a thickness of 10 μm was formed on both the inner and outer surfaces of the shroud cylinder in the same manner as in Example 1 above, except that Al was used as the reactive gas and O ₂ was used as the reactive gas. We investigated the erosion caused by Ga. As a result, no corrosion by Ga was observed on both the inner and outer surfaces of the shroud cylinder.

Comparative Example First, a cylindrical body for a shroud having a cooling fluid circulation portion on the peripheral wall was made from an aluminum material. After attaching 1g of Ga to both the inner and outer surfaces of the shroud cylinder, heat it at 200℃ for 24 hours → with liquid nitrogen.
A thermal cycle test of 30 minutes of cooling was repeated for 6 cycles to examine the corrosivity caused by Ga. As a result of observing both the inner and outer surfaces of the cylinder, corrosion by Ga was observed.

Effects of the Invention In the method for manufacturing a shroud for semiconductor manufacturing equipment according to the present invention, after an aluminum shroud cylinder having a cooling fluid circulation portion on the peripheral wall is fabricated, at least the inner surface of the inner and outer surfaces thereof is subjected to an ion plating method. Therefore, it is characterized by forming a film that is resistant to corrosion against gallium, so it is lighter than conventional stainless steel products, has good thermal conductivity, and is resistant to corrosion against gallium. However, it is possible to easily manufacture shrouds equivalent to those made of stainless steel. especially,
Because it has excellent thermal conductivity, it is possible to shorten the baking time during semiconductor film formation compared to conventional products, and it also improves cooling efficiency when cooling fluid is flowed through the cooling fluid circulation section. is improved, and the residual gas adsorption rate during semiconductor film formation is improved.

Furthermore, since the shroud cylinder is made from aluminum, it is easier to process than when it is made from stainless steel.

In addition, since the film is formed using the ion plating method, no moisture is adsorbed in this tank during film formation, so when shrouds manufactured by this method are used in MBE equipment, etc. For this purpose, it is sufficient to simply perform the conventional baking process during the formation of semiconductor films.

In addition, since the film is formed using the ion plating method, this film has excellent thermal cycling properties, and it can be heated to about 250℃ for degassing purposes and liquid nitrogen during semiconductor film formation. Even after repeated cooling, the film does not peel or crack.

Furthermore, since aluminum has a lower gas release coefficient than stainless steel, there is less risk of lowering the degree of vacuum in the semiconductor film deposition chamber in the MBE apparatus.

Claims (1)

[Claims] 1. After making an aluminum shroud cylinder having a cooling fluid circulation part on the peripheral wall, a film having corrosion resistance against gallium is formed on at least the inner surface of both the inner and outer surfaces thereof by an ion plating method. A method for manufacturing a shroud for semiconductor manufacturing equipment, characterized by: