JPH0376111A - Vapor deposition process and device therefor - Google Patents

Abstract

PURPOSE:To enable excellent vapor deposition process to be performed even if a hardly thermal-cracked material constituent such as phosphine or easily reactive material constituent at relatively low temperature are simultaneously used by a method wherein multiple material constituents are respectively fed to the surfaces of horizontally rotating substrates and mixed with each other on the substrate. CONSTITUTION:While a holding base 13 is being turned in the horizontal direction through the intermediary of an axial member 14, the heater of the holding base 13 is actuated to heat a substrate P at specific temperature so as to lead phosphine and trimethylgallium, while being accompanied by carrier gas, respectively through the first gas leading-in pipe 15 and the second gas leading-in pipe 16. Through these procedures, phosphine in preheated and partly thermal- cracked state is fed to the substrate surface while trimethylgallium is fed, as it is, to the substrate surface to be thermally cracked thereon and then mixed with the thermally cracked phosphine so that vapor deposited gas may be produced and reacts, on the surface of the substrate, to produced a reaction product which is deposited on the substrate surface to form a thin film thereon.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a method for producing a vapor-phase growth gas by mixing raw material components in Groups II and V of the Periodic Table, or raw material components in Groups R1M and Group II of the Periodic Table. This is supplied onto a substrate heated to a predetermined temperature in a vapor phase growth chamber, thermally decomposed on the substrate, and reaction products resulting from the thermal decomposition are deposited on the substrate surface to form a thin film. The present invention relates to a vapor phase growth method and an apparatus therefor, which are suitable for using a raw material component that is difficult to thermally decompose or a raw material component that reacts at a relatively low temperature.

[Conventional technology]

In the vapor phase growth method, raw material components are usually mixed in advance to form a vapor phase growth gas, which is then supplied onto a substrate in a vapor phase growth chamber.

However, in vapor growth gases that contain raw material components that are difficult to thermally decompose, such as phosphine (PH3, a raw material component of group V), the amount of phosphine used increases relative to other raw material components of group II, resulting in an increase in cost. At the same time, it places an excessive burden on the abatement equipment, and raw material components that easily react at relatively low temperatures, such as trimethyl zinc (TMZn11
Even when forming a Zn5e thin film using hydrogen selenide (H2Se, a raw material component in group I) and hydrogen selenide (H2Se, a raw material component in group This has the disadvantage that good vapor phase growth cannot be carried out due to the formation of .

Therefore, when these raw material components are used, they are individually supplied into a vapor phase growth chamber and mixed in the vapor phase growth chamber to form a vapor phase growth gas.

For example, in the conventional apparatus illustrated in FIG. The heater 1 of the introduction tube 2 heats the trimethyl gallium to 600 to 1000°C, and trimethyl gallium is directly introduced to the upstream side of the substrate P in the vapor growth chamber 4 through the gas introduction tube 3. The mixed gases are supplied onto the substrate P as a vapor growth gas.

According to the above apparatus, phosphine is partially decomposed by the heater 1 and a large amount of active species are generated, so that a desired thin film can be formed using a smaller amount of phosphine than when no heating is performed. Note that the heater 1 is not required when trimethyl zinc and hydrogen selenide are individually introduced into the vapor phase growth chamber.

[Problem to be solved by the invention]

However, even if the individual raw material components are mixed in the vapor phase growth chamber 4 as described above, for example, if phosphine and trimethyl gallium are simultaneously supplied into the vapor phase growth chamber 4,
Immediately after mixing, trimethyl gallium comes into contact with high-temperature phosphine and thermally decomposes, and some reaction products are generated before reaching the substrate P, resulting in the inconvenience that good vapor phase growth cannot be performed. Further, trimethyl zinc and hydrogen selenide also react with each other immediately after being mixed in the vapor growth chamber, resulting in a similar problem.

Therefore, in order to avoid this, for example, the open end of the gas introduction tube 2 for phosphine in the conventional apparatus shown in FIG. Although it has been proposed to prevent this, the mixing state on the substrate surface is insufficient, and a good vapor phase growth gas is not generated, so that good vapor phase growth cannot be performed.

It is an object of the present invention to provide a vapor phase growth method and an apparatus therefor that solve these problems.

[Means to solve the problem]

In view of the above-mentioned disadvantages, the present inventor conducted various studies and found that a good vapor phase growth gas can be produced by supplying a plurality of raw material components parallel to the substrate surface and mixing them on the substrate surface. The present invention was completed based on this.

The present invention has been made based on the above knowledge, and claims 1
In the invention described in , a plurality of raw material components are each supplied to the substrate surface of a horizontally rotated substrate at the same height as the substrate surface and parallel to the substrate surface, and mixed on the substrate surface. The method is characterized in that a vapor phase growth gas is generated, the vapor phase growth gas is thermally decomposed on the substrate surface, and a reaction product is deposited on the substrate surface to form a thin film.

In addition, the invention according to claim 2 has a substrate exchange chamber connected to the lower part of the vapor growth chamber, and the holding table on which the substrate is placed can be horizontally rotated and can be moved up and down between the vapor growth chamber and the substrate exchange chamber. In a vapor-phase growth apparatus installed in It is characterized in that it is arranged close to the table, and the lower surface of each flow channel is set at the same height as the surface of the substrate that is horizontally rotating in the vapor growth chamber.

[Function] According to the vapor phase growth gas and apparatus thereof according to the present invention, the individual raw material components are mixed for the first time on the substrate, and reaction products are generated immediately after, so that good vapor phase growth can be performed.

Although the raw material components individually supplied onto the substrate are not sufficiently mixed at the supply end, they are mixed with other raw material components during the course of flowing over the substrate, and a good vapor phase growth gas is formed. Since the substrate is horizontally rotated as described above, even if some insufficient mixing occurs at the supply end of the raw material components, it is averaged out and a uniform thin film is formed on the substrate.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a front cross-sectional view of an embodiment of an apparatus to which the method of the present invention is applied, and FIG. 2 is a cross-sectional view taken along the line ■-■ in FIG. At the bottom, a substrate exchange chamber 12 for exchanging film-formed substrates and unprocessed substrates is installed, and the substrate exchange chamber 12 has a holding table 13 at the upper end for holding and heating the substrate, so that both chambers can be exchanged. As well as going up and down between 11 and 12,
A shaft member 14 configured to be horizontally rotatable is provided.

In addition, the vapor growth chamber 11 has three gas introduction pipes 1 on the side.
5, 16, 17 and one gas outlet pipe 18 are provided, and these gas inlet pipes 15, 16, 17 are at the same height on the side of the vapor growth chamber 11, and at an angle of 60 degrees to each other. The flow channels 19, 20, and 21 each have a fan shape that expands toward the substrate P side.

The flow channel 19, 20, 21 has an upper surface part of the opening end on the substrate side connected to a circular top plate 22 forming the ceiling surface of the holding table 13, and a lower surface part of the opening end on the substrate side forming the ceiling surface of the holding table 13. The upper substrate surface (substrate P is thin, so it is practically the holding base 13
(almost the same as the top surface of the holding table 13), and
The holding base 1 is cut out in an arc shape according to the shape of the side surface of the holding base 1.
It is close to 3. In addition, in the example device shown in the figure, the first
In order to use the gas introduction pipe 15 for introducing phosphine, a heater 23 is provided at the outlet end of the gas introduction pipe 15.

Next, a case will be described in which three substrates P are placed on the holding table 13 and a GaP thin film is formed on the substrates P using this vapor phase growth apparatus 10.

First, in the substrate exchange chamber 12, an unprocessed substrate P is placed on the holding table 13, and the shaft member 14 is moved upward to set the holding table 13 at a predetermined position in the vapor growth chamber 11. The upper surface of P is at the same height as the lower surface of the flow channels 19, 20, and 21.

Next, the holding table 13 is rotated in the horizontal direction via the shaft member 14, and the heater (not shown) of the holding table 13 is activated to raise the temperature of the substrate P to a predetermined temperature, and the first gas introduction pipe is heated. Phosphine is introduced into 15, and trimethyl gallium is introduced into the second gas introduction pipe 16 together with a carrier gas.

As a result, phosphine is preheated by the heater 23 and is supplied to the substrate surface in a partially decomposed state, while trimethyl gallium is supplied as it is to the substrate surface and is thermally decomposed on the substrate surface to form the thermally decomposed phosphine. At the same time that the vapor phase growth gas is mixed and generated, the generated vapor phase growth gas reacts on the substrate surface to generate a reaction product, which is deposited on the substrate surface to form a thin film. .

In this way, the raw material components are either mixed in a thermally decomposed state on the substrate surface and immediately start the reaction, or because the reaction is on the substrate surface, the reaction products are deposited on the substrate surface and a good thin film is formed. It is formed.

Note that although the raw material components at the open end of each flow channel are not sufficiently mixed with other raw material components, they mix with other raw material components during the process of flowing over the substrate parallel to the substrate surface, resulting in good vapor phase growth. Since the gas is formed and the substrate is horizontally rotated as described above, the mixing state becomes uniform, and a uniform thin film is formed on the substrate.

Once a predetermined thin film is formed on the substrate and a film-forming substrate is obtained,
After stopping the introduction of the vapor growth gas and purging the inside of the vapor growth chamber 11, the shaft member 14 is moved down to transport the holding table 13 into the substrate exchange chamber 12, and a film is formed on the holding table 13. After the substrate and the untreated substrate are transferred, the shaft member 14 is moved upward and vapor phase growth is performed again.

In the above embodiment, the gas introduction pipes 15 and 16 were used, but the present invention is not limited to this, and any two gas introduction pipes may be used. In this case, the flow direction of the two raw material components is 180 degrees.
Preferably, the angle is less than 120 degrees, preferably less than 120 degrees.

In addition, in the apparatus 10 of the embodiment, three gas introduction pipes are provided, so that three types of raw material components can be simultaneously supplied to carry out vapor phase growth. Any number of gas introduction pipes may be provided as long as they can be supplied in parallel.

Furthermore, in the embodiment device 10, the top plate 22 forming the ceiling surface of the holding table 13 is connected to the flow channels 19, 20, 2.
This top plate 22
If it is detachably provided on the holding stand 13, it can be easily replaced with a cleaned top plate in the board exchange chamber 12.

In the above explanation, we have explained the case of forming a GaP thin film on the substrate, but it can be carried out in the same way when forming a Zn5e thin film. In this case, trimethyl zinc and hydrogen selenide are mixed on the substrate surface and gas Along with forming phase growth gas,
This vapor phase growth gas immediately reacts on the substrate surface, and a reaction product is deposited on the substrate to obtain a film-formed substrate. In addition, Zn5
The heater 23 is not necessary when forming an e-thin film.

〔Effect of the invention〕

As described above, according to the vapor phase growth method and its apparatus according to the present invention, a plurality of raw material components are respectively supplied to the substrate surface of the horizontally rotating substrate and mixed on the substrate surface. Even when using a raw material component that is difficult to thermally decompose, such as phosphine, or a raw material component that reacts at a relatively low temperature, good vapor phase growth can be performed.

[Brief explanation of drawings]

Figures 1 and 2 show an example device to which the method of the present invention is applied,
FIG. 1 is a sectional front view thereof, FIG. 2 is a sectional view taken along the line -■ in FIG. 1, and FIG. 3 is a sectional front view of the conventional device. 10... Vapor phase growth apparatus 11... Vapor phase growth chamber 12
... Board exchange room 13 ... Holding stand 15, 16
．． 17... Gas inlet pipe 18... Gas outlet pipe 19
．． 20.21...Flow channel 22...Top plate P...Substrate

Claims (1)

[Claims] 1. A plurality of raw material components are each supplied to the substrate surface of a horizontally rotated substrate at the same height and parallel to the substrate surface, and mixed on the substrate surface. vapor phase growth, characterized in that a vapor phase growth gas is produced, and the vapor phase growth gas is thermally decomposed on the substrate surface to deposit a reaction product on the substrate surface to form a thin film. Method. 2. A vapor phase growth apparatus in which a substrate exchange chamber is connected to the lower part of the vapor phase growth chamber, and a holding table on which the substrate is placed is horizontally rotatable and movable up and down between the vapor phase growth chamber and the substrate exchange chamber, Gas introduction pipes for supplying each of the plurality of raw material components are provided on the side surfaces of the vapor phase growth chamber, and the flow channels of each gas introduction pipe are arranged so as to be close to a holding table elevated within the vapor growth chamber, and A vapor phase growth apparatus characterized in that the lower surface of each flow channel is set at the same height as the surface of a substrate rotating horizontally within a vapor phase growth chamber.