JPH02141489A - Method and apparatus for producing compound semiconductor by boat growth method - Google Patents

Abstract

PURPOSE:To prevent the sticking of a reactor and a boat and to prevent the deformation of the boat so as to allow the repetitive use of the boat and to reduce its cost by interposing boat rests consisting of an inert material which is stable at a high temp. between the reactor and the boat. CONSTITUTION:The boat rests 105 formed of the inert material, for example, boron nitride, more preferably thermally decomposed boron nitride, aluminum nitride, silicon nitride, etc., are interposed between the quartz reactor 101 and the boat 103 and a compd. semiconductor single crystal is grown. The deformation of the boat is prevented in spite of the repetitive use of the boat 103 if the boat rests 105 are made into the shape complying with the outside shape of the side face of the boat 103. The growth of the crystal in the state in which cristobalite layers are formed by the repetitive use is possible and the lower cost of the production and the higher quality of the crystal are attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and apparatus for manufacturing a ■-■ group compound semiconductor such as GaAs using a port growth method.

[Conventional technology]

In general, a -V group compound semiconductor ingot such as GaAs is often manufactured by inserting a quartz port containing a seed crystal into a reactor made of a quartz tube, and growing a single crystal within the port.

In such a port growth method, the operating temperature range of the port is 1,200 to 1,300° C., which is above the softening point of quartz, so the port is deformed after use, so it is usually disposable.

[Problem to be solved by the invention]

By the way, in the port growth method, polycrystalization occurs when wetting occurs between the GaAs melt and the port, but it is known that polycrystalization can be avoided by forming a cristobalite layer on the port surface. . This cristobalite layer is formed by repeatedly using the port at high temperatures, but there is a problem in that the port deforms when used repeatedly.

Therefore, in order to enable repeated use of the port, the wall thickness was increased to several mm, and the port shape was configured so that the ingot could be removed immediately after the ingot was manufactured to allow crystal growth. A problem arose in that it adhered and could not be removed. In this case, it is quite difficult to remove by dissolving it with hydrofluoric acid, and the cristobalite layer formed on the inner surface of the port will also be dissolved by the hydrofluoric acid, which will affect the subsequent crystallinity.

In addition, since the operating temperature is near the softening point of quartz, deformation will inevitably occur even if the wall thickness is increased, and this deformation is greatest during the first use, and although the degree of deformation will decrease as it is used. Deformation cannot be prevented, and even if the operating temperature is lowered as much as possible, deformation cannot be completely prevented. When deformation occurs, the reactor that has been used up until now becomes unusable, or a reactor with a larger diameter must be used.

The present invention is intended to solve the above-mentioned problems, and it prevents adhesion between the reactor and the port, eliminates deformation of the photo, enables repeated use, and reduces manufacturing costs.
It is an object of the present invention to provide a compound semiconductor manufacturing method and manufacturing apparatus using a port growth method, which enables higher quality crystal growth.

[Means to solve the problem]

To this end, the present invention is characterized in that a port receiver made of an inert material is interposed between the port and the reactor in a port growth method in which a port is placed in a reactor and a single crystal is grown within the port. In addition, in compound semiconductor manufacturing equipment in which a port is inserted into a reactor to grow a single crystal, at least one port receiver made of an inert material is interposed between the reactor and the port, and the port receiver is shaped to the external shape of the port side. It is characterized by the combination.

[Effect]

In the present invention, a photoreceptor made of an inert material such as boron nitride, preferably pyrolytic boron nitride, aluminum nitride, silicon nitride, etc. is interposed between the reactor and the port, thereby preventing the port and the reactor from adhering to each other. In addition, by matching the shape of the port receiver to the side profile of the port, deformation of the port can be prevented even if the port is used repeatedly.
Repeated use enables crystal growth with a cristobalite layer formed, making it possible to reduce manufacturing costs and improve crystal quality.

〔Example〕

Examples will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the present invention, in which 101 is a reactor, 103 is a port, and 105 is a port receiver.

In the figure, a reactor 101 is made of ordinary quartz, and contains pyrolytic boron nitride (Pyrolitic Bor nitride).
Insert the port receiver 105 consisting of N1tride; pBN). pBN is stable up to about 2000°C, has high strength, and does not react with quartz. 'Then, there is a port 1 with a wall thickness of about 5+++m inside the reactor.
03 and support it with the port receiver 105.

A seed crystal (not shown) is placed in the port 103, and 1
Crystal growth is performed at 200-1300°C.

When crystal growth was performed using this method, the port and the reactor did not stick together and the port could be easily taken out.

In the above embodiment, the port is made of pBN, but other materials such as aluminum nitride, silicon nitride, etc. may also be used.

By the way, in the embodiment shown in Fig. 1, the port receiver 105 only functions as a spacer between the reactor and the port, and even if the wall thickness of the port is increased to about 4 to 9 mm, which is normally used, it will not work several times. Deformation inevitably occurs during use.

The port typically has a shape as shown in FIG. FIG. 2(a) is a plan view, FIG. 2(b) is a cross-sectional view, and FIG. 2(c) is a longitudinal sectional view.

FIG. 3 is a diagram showing an embodiment using a port receiver that prevents deformation of the port and enables repeated use. Figure 3 (
a> is a plan view, Fig. 3(b) is a cross-sectional view, Fig. 3(c)
is a vertical sectional view.

In this example, the port receiver is shaped to match the side profile of the port shown in Figure 2, and by placing the port inside and growing crystals, the port is prevented from deforming and can be used multiple times. This makes it possible to significantly reduce costs. Moreover, by repeated use, a cristobalite layer is formed on the inner surface of the port, which prevents contamination of pure substances from the port and allows high-quality crystal growth to occur.

Note that the port receiver shown in the embodiment of FIG. 3 has a structure in which the side surfaces of the longitudinal ends of the ports are not supported.
It is also possible to have a structure in which the longitudinal end side faces are also supported, and by making the bottom of the port receiver match the inner shape of the reactor, it is possible to make it strong against vibrations.

〔Effect of the invention〕

As described above, according to the present invention, by interposing the port receiver made of an inert material that is stable at high temperatures between the reactor and the port, it is possible to prevent adhesion between the port and the reactor, and to prevent the port receiver from colliding with the reactor. By matching the shape to the outer shape of the port side surface, the port can be prevented from deformation and can be used repeatedly, which significantly reduces the cost of the port growth method, and enables high-quality crystal growth by forming a cristobalite layer.

[Brief explanation of the drawing]

FIG. 1 is a side view showing one embodiment of the present invention, and FIG. 2 is a side view showing one embodiment of the present invention.
3 shows the port shown in FIG. 1, FIG. 3 shows the port in FIG. 1, FIG. (a) is a plan view, (b) is a cross-sectional view, and (c) is a longitudinal cross-sectional view. 101...Reactor, 103...Port, 105...
...Port receiver. Applicant: Mitsubishi Monsanto Chemicals Co., Ltd. (1 other person)

Claims (6)

[Claims] (1) A port growth method in which a port is placed in a reactor and a single crystal is grown within the port, which is characterized in that a port receiver made of an inert material is interposed between the port and the reactor. Compound semiconductor manufacturing method. (2) A compound semiconductor manufacturing method using a port growth method according to claim 1, wherein the port is used repeatedly. (3) The method of manufacturing a compound semiconductor by a port growth method according to claim 1, wherein the inert material is boron nitride, aluminum nitride, or silicon nitride. (4) In a compound semiconductor manufacturing apparatus in which a port is inserted into a reactor to grow a single crystal, a port growth method characterized in that at least one port receiver made of an inert material is interposed between the reactor and the port. Compound semiconductor manufacturing equipment by (5) In a compound semiconductor manufacturing device that grows a single crystal by inserting a port into a reactor, a port receiver made of an inert material and shaped to match the external shape of the side surface of the port is interposed between the reactor and the port. Compound semiconductor manufacturing equipment using the characteristic port growth method. (6) The compound semiconductor manufacturing device using the port growth method according to claim 3 or 4, wherein the inert material is pyrolytic boron nitride, aluminum nitride, or silicon nitride.