JPS6272109A - Manufacture of compound semiconductor device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to a method for manufacturing a compound semiconductor device. More specifically, the present invention relates to a method of manufacturing a compound semiconductor device in which a -V group compound semiconductor is laminated on a Si substrate, and is utilized as a key technology for manufacturing a compound semiconductor device.

(b) Conventional technology Compound semiconductors such as QaΔS are utilized in optical semiconductor devices and high-speed devices by taking advantage of their distorted Rlfi. For example, excellent efficiency can be expected by forming a P N )B combination on a compound semiconductor to construct a solar cell, so the light-receiving surface side is constructed using three layers of GaA, and a substrate supporting this Qa As E is used. A solar cell using a relatively light 81 substrate is being researched as a space solar cell that requires a reduction in weight. Also, in terms of price,
Since compound semiconductors such as GaAs are disadvantageous compared to 81 substrates, there is a tendency to develop compound semiconductor devices in which GaASIH is formed on a Si substrate. Conventionally, the following three methods have been used to form and cover a Ga AS layer on a 3i substrate.

■ This method uses a one-piece system with a lattice constant between $1 and Ga AS, and as shown in Figure 3, there is a layer between the 81 substrate (1) and the compound semiconductor layer (5). A lattice matching layer (6) is formed. This lattice matching layer (6) is a crystal layer of, for example, Qe si , Ga ASP, etc. whose warm crystal composition is changed in stages. A conventional compound semiconductor layer (5) is formed on this lattice matching 1 by epitaxial growth.

■ This method uses 81 substrates (1) as shown in Figure 4.
This is a method of forming a Ge single crystal layer (2) between a compound semiconductor layer (5) and a compound semiconductor layer (5), and the formation of this Gei# crystal layer (2) can be performed using, for example, electron beam evaporation W (EB) method, ion cluster beam evaporation (ICB) method, molecular beam epitaxy (
The compound semiconductor layer (5) is formed using the molecular beam epitaxy (MBE) method and the vapor phase deposition ff<(CVD) method W.
It is formed using a metal organic chemical vapor deposition (MOCVD) method or a metal organic chemical vapor deposition (MOCVD) method.

■ This method uses a Si substrate (1) as shown in Figure 5.
Using molecular beam epitaxy (MBE) or metal organic chemical vapor deposition (MOCVD), for example,
This is a method of directly forming a compound semiconductor layer (5) such as.

(C) Problems to be Solved by the Invention However, in the method (3) above, it is necessary to minimize the rate of change in the lattice constant of the lattice matching layer (6);
Growth control becomes complicated. Further, in order to suppress the influence of internal stress in the lattice matching layer (6) on the crystallinity of the compound semiconductor layer (5), it is necessary to increase the thickness of the lattice matching layer M(6). For example, in the case of 3i and GaAS,
The thickness of this lattice matching layer (6) is required to be on the order of several tens of thousands of tons, so it does not meet the requirements for lower costs and lighter weight.

In method (2) above, both the 81 substrate and the single-crystal Ge layer are heated to a high temperature (for example, about 600 to 700°C) by heating the substrate, so the Si substrate (1) and the compound semiconductor layer (
Due to the difference in the coefficient of thermal expansion between the layers (5), a large lattice strain occurs during the cooling process from the growth temperature, and this lattice strain remains in the compound semiconductor layer (5).

In particular, when Qa AS is formed as the compound semiconductor layer (5) at 3A or more, this lattice strain causes GaAS
@There is a problem that cracks occur in the long layers.

In the above method (2), it is difficult to obtain a good quality compound semiconductor layer (5) due to residual lattice distortion due to the difference in thermal expansion coefficients, similar to the above method (2).

This invention has been made to solve the above-mentioned problems, especially the above-mentioned problem (2). The purpose is to provide a method.

(d) Means and operation for solving the problems Thus, according to the present invention, after forming a germanium single crystal layer on a silicon base plate, I[
In forming the I-VM compound semiconductor layer, the above-mentioned ■-
Forming an m-v1tk compound semiconductor layer while irradiating the surface of the germanium single crystal layer with electromagnetic waves that are not absorbed by the V group compound semiconductor layer but can heat the germanium single crystal by being absorbed by the germanium single crystal. A method for manufacturing a compound semiconductor device with features is provided.

The Ge single crystal layer in this invention is formed by a commonly used method.
For example, it is formed on a predetermined 81 substrate using an electron beam evaporation (EB) method, an ion cluster beam evaporation (ICB) method, a single molecular beam epitaxy (MBE) method, a vapor phase epitaxy (CVD) method, or the like.

Note that, before forming the Ge single crystal layer on the 3i substrate, it is preferable to perform an operation of cleaning the substrate surface by a commonly used method, such as a 1-IF9a process.

(2) As for the electromagnetic waves that are not absorbed by the V group compound semiconductor layer but are absorbed by the Ge1t1 crystal layer, it is preferable to use a laser for each electromagnetic wave in the near-infrared or infrared region, such as a YAG laser (wavelength: 1.06 cm). is preferably used. This laser is used to irradiate the surface of the Ge single crystal, and
Even if the single crystal surface is set at the optimal temperature for forming a ■-V group compound semiconductor layer (for example, approximately 600 to 700°C when forming GaAs), within the time required to form a semiconductor layer, The temperature near the interface between the Ge single crystal layer and the 81 substrate does not rise to the set surface temperature of the Ge single crystal layer (for example, even if the surface temperature of the Ge single crystal layer is raised to 600 to 700 °C, the temperature at 50 °C during growth
(The temperature rises only to around 0℃). Therefore, the 3i board and ■-
The strain generated between the V-group compound semiconductor layer and the V-group compound semiconductor layer is significantly reduced compared to conventional substrate heating methods.

(2) For example, GaAs is used for the -v group compound semiconductor layer.

GsAρAs, GaP, InP, GaAsP
.

Examples include single crystal layers made of InGaP, InGaAsP, etc., and can be formed using commonly used methods such as molecular beam epitaxy (MBE) and metal organic vapor deposition (MOCV).
D) The film can be formed at an optimal temperature for forming a specific IL film, for example, at a temperature equal to epitaxy, using a method such as method D). Therefore, the electromagnetic wave irradiation conditions may be determined and irradiated so that the surface temperature of the Ge single crystal layer is set to the optimum temperature according to the type and growth method of the single crystal layer.

(e) Examples The present invention will be explained below using examples. However, the present invention is not limited thereby.

FIGS. 1 and 2 are structural explanatory diagrams illustrating a method for manufacturing a compound semiconductor device of the present invention.

First, convert the 3i board (1) to HF! 2! ! 1) G of jIT was removed using the electron beam evaporation (EB) method at a substrate temperature of 450°C in a vacuum of 1xlO'pa or less to remove the oxide film.
e A single crystal layer (2) was formed. Next, a Ge single crystal layer (2
)Nd:YAG laser (wavelength: 1.06)a on the surface
) to irradiate the surface of the Ge single crystal layer (2) with laser light (4) to a temperature of about 600 to 700°C.
Ga and AS are supplied from individual BN crucibles while setting the strength, and Qa is produced by molecular beam epitaxy (MBE) method.
As shown in Figure 2, the As single crystal layer (3) is grown epitaxially to form a compound semiconductor device. I built J.

In order to examine the effects of the compound semiconductor device of the present invention (hereinafter referred to as sample A) manufactured as described above, other conditions were the same, but instead of the method using laser light irradiation, the conventional method ( A sample in which a Ga As single crystal layer was formed by heating a Ge single crystal layer using a substrate heating method (
A sample (hereinafter referred to as sample B) was prepared.

In order to compare the crystallinity of samples A and B,
As a result of measuring the half-width of the diffraction peak by the X-ray two-crystal method, the half-width of sample A was smaller than that of sample B.
It was confirmed that this had better crystallinity. Therefore, it was found that the production method of the present invention suppresses the occurrence of lattice distortion.

(f) Effects of the Invention As described above, according to the present invention, the Ge single crystal layer and the
By suppressing the temperature rise near the interface with the 3i substrate and reducing the temperature difference with the compound semiconductor layer, it is possible to form a compound semiconductor layer with less lattice strain on the 3i substrate. Cracks in layers and variations in quality can be prevented, making it possible to manufacture high-quality, low-cost, and lightweight compound semiconductor devices. Therefore, this is a manufacturing method that can be effectively applied to space solar cells and the like.

[Brief explanation of drawings]

Figures 1 and 2 provide a detailed explanation of the invention (old=-
3i substrate, (2)...Ge single crystal layer, (3
)...GeAS single crystal layer, (4)...
・Ray+f light, (5)...Compound semiconductor layer,
(6)... Lattice matching layer. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. After forming a germanium single crystal layer on a silicon substrate, in forming a III-V group compound semiconductor layer on the germanium single crystal layer, the III-V group compound semiconductor layer is A compound semiconductor characterized in that a III-V compound semiconductor layer is formed while irradiating the surface of the germanium single crystal layer with electromagnetic waves that can heat the germanium single crystal by being absorbed by the germanium single crystal without being absorbed by the germanium single crystal. Method of manufacturing the device. 2. The manufacturing method according to claim 1, wherein the electromagnetic wave is a laser. 3. III-V compound semiconductor layer is GaAs, GaAlA
s, GaP, InP, GaAsP, InGaP or I
2. The method according to claim 1, wherein the layer is a single crystal layer of nGaAsP.