JPH04299525A - Manufacture of element - Google Patents

Abstract

PURPOSE:To obtain a large-area single crystal layer at a little growth amount by a method wherein a single crystal substance liquid phase growth layer is grown by a liquid phase growth method and when an element is manufactured, an impurity is added into a liquid phase. CONSTITUTION:A single crystal substance vapor growth layer 2 is grown on an Si substrate 1. Then, a mask layer 3 is deposited on the surface of the layer 2. After that, a window 4 is formed according to a pattern of a purposed element. A single crystal substance liquid phase growth layer 5 is grown through this window 4 by a liquid phase epitaxial growth method. At the time of this liquid phase growth, an impurity is added into a liquid phase, whereby the ratio of the growth rate of the layer 5 in the horizontal direction to the growth rate of the layer 5 in the vertical direction is further increased and the effect is heightened more remarkably. The impurity is a single substance to be dissolved in Sn, Ga or the like which is used as a solvent, such as Si.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a monolithic device formed of a single crystal material on a single crystal substrate.

0002

[Prior Art] In recent years, Si manufacturing technology, which has high reliability, has been used to fabricate semiconductors on insulators, or SOI (Semiconductor On Ins).
By combining various types of sensors and combining MOS and bipolar technologies, it is believed that by combining these with compound semiconductors, devices with complex information processing mechanisms can be obtained. .

Conventionally, in order to manufacture such monolithic elements, research has been conducted on deposition recrystallization methods, epitaxial deposition methods, and single crystal separation methods. For example, the technology to grow GaAs directly on a Si substrate is based on the characteristics of the Si substrate (capable of large area, mechanically robust, high thermal conductivity, light weight, low cost) and the electro-optic effect (high mobility, etc.) that Si does not have. Si and GaAs are attracting attention as a material that can be combined with the characteristics of GaAs, which has a direct transition bandgap).
Misfit dislocations originating from a lattice mismatch of about 4% in s affect the crystallinity of the deposited layer above it, narrowing the range of applications as devices.

In order to incorporate circuit elements into a deposited layer with good reproducibility, firstly it is necessary to form a deposited layer with good crystallinity, and secondly, it is necessary to form a deposited layer that has already been formed in the lower layer of the deposited layer. A low-temperature growth technique is needed to grow the deposited layer without damaging the device being used. In order to solve these problems, the present inventors have already published Japanese Patent Application Laid-Open No. 1-161822.
We are proposing a method. That is, a step of depositing a single crystal material on a single crystal substrate by a vapor phase growth method, a step of depositing a mask layer with a window on the surface of the single crystal material, and a step of depositing a single crystal material through the window of the mask layer by a liquid phase growth method. This is a device manufacturing method that consists of a process of growing a substance.

[0005]

[Problems to be Solved by the Invention] When the above-mentioned technique is applied to the epitaxial growth of GaAs on a Si substrate, for example, the liquid phase can be grown from the window of the mask layer onto the mask layer without being affected by misfit transitions due to lattice mismatch. The growth allows epitaxial growth of a single crystal layer. As shown in FIG. 1, this liquid phase growth progresses in the vertical direction V and the horizontal direction H, but when it is performed in the horizontal direction, its crystallinity is not affected by the underlying layer. This is due to the plane orientation of the single crystal substrate in which the single crystal liquid phase growth layer is faceted in the final liquid phase growth (for example, in the case of GaAs, {111
} or {100 }) induces a difference in growth rate in the vertical and lateral directions with respect to the substrate, and increases the growth rate in the horizontal direction.
This is due to the fact that relatively large growth can be achieved.

However, in reality, the horizontal growth edge becomes a low-index plane at a relatively early stage, making it difficult to obtain a sufficiently large growth layer and making it difficult to apply to various devices. A method of obtaining layers is needed. In view of this problem, the inventors of the present invention conducted intensive studies on a method for increasing the crystal growth rate in the horizontal direction during liquid phase growth, and as a result, completed the present invention. In other words, an object of the present invention is to increase the crystal growth rate in the horizontal direction during liquid phase growth, thereby creating a large-area device with good crystallinity that can be applied to various devices.

[0007]

[Means for Solving the Problems] That is, the gist of the present invention is as follows. A step of depositing a single crystal material on a single crystal substrate by a vapor phase growth method, a step of depositing a mask layer with a window on the surface of the single crystal material, and a step of depositing the single crystal material through the window of the mask layer by a liquid phase growth method. A method for manufacturing an element comprising a step of growing a single crystal substance, the method comprising adding an impurity to a solution when growing a single crystal substance by the liquid phase growth method.

The present invention will be explained in more detail below with reference to FIG. FIG. 1 is a perspective view of a device according to Example 1 of the present invention, and its front side shows a cross section. In the present invention, the single crystal material is Si
, Ge, etc., or GaAs, GaP,
InP, InAs, AlAs, AlSb, GaSb, G
aAlAs, GaAlP, GaAsP, InGaAs,
It is made of binary to multi-component materials such as GaAsSb and InGaAsP. As shown in FIG. 1, first, a single crystal material vapor phase growth layer 2, for example GaAs, is deposited on a single crystal substrate, for example, a Si substrate 1, by metal organic vapor phase epitaxy.
Grow single crystals. As the vapor phase growth method, a molecular beam epitaxial growth method or a similar method can be used in addition to the organometallic vapor phase growth method.

Next, a mask layer 3 is deposited on the surface of the monocrystalline material vapor-phase grown layer 2 . The material of the mask layer is SiO
A film with a thickness of about 200 nm is deposited using a method such as plasma CVD or sputtering. Thereafter, windows 4 are formed according to the intended pattern of the element using photolithography technology. On the thus obtained single crystal vapor phase growth layer, a single crystal material liquid phase growth layer 5 is grown by a liquid phase epitaxial growth method or the like through a window.

The growth of a single crystal material by this liquid phase growth proceeds in the vertical direction V and the horizontal direction H.
In the case of As, by increasing the horizontal growth rate by using {111 } or {100 }),
It becomes possible to grow a high-quality, large-area single-crystal material that is not affected by crystal defects or distortions of the single-crystal material deposited below the single-crystal material. By adding impurities to the solution during liquid phase growth, the ratio of the growth rate in the horizontal direction to the vertical direction is further increased, and the effect becomes even more remarkable. The impurities mentioned here include Si,
Ge, Sn, Zn, P, Cd, B, Se, S, Te, M
n, etc., is a simple substance that dissolves in Sn, Ga, etc. used as a solvent. Note that the single crystal materials used for the single crystal substrate, the single crystal vapor phase growth layer, and the single crystal liquid phase growth layer do not have to be the same material, and different materials can be combined depending on the structure of the target element. .

[0011]

EXAMPLES AND COMPARATIVE EXAMPLES Examples of the present invention will be described in detail with reference to the accompanying drawings.

(Embodiment 1) FIG. 1 is a perspective view of an element according to an embodiment of the present invention, and its front side shows a cross section. A 2-inch wafer consisting of a (100) plane of Si single crystal was organically cleaned, and the oxide film was removed using HF to obtain a single crystal substrate 1. A GaAs vapor phase growth single crystal layer 2 was grown on this by molecular beam epitaxial growth. .5 μm. The growth conditions were a substrate temperature of 600° C. and a growth rate of 1.4 μm/hour. Then, the thickness was reduced to 200 mm by plasma CVD.
depositing a mask layer 3 of SiO2 of nm;
The mask layer was scribed to a size of 9 mm x 14 mm, and a linear window 4 with a width of 5 μm was opened in the mask layer using photolithography. Next, using a slide boat type liquid phase epitaxial apparatus, liquid phase epitaxial growth was performed on the mask through the window of the vapor phase grown GaAs single crystal. This liquid phase epitaxial growth was performed by a two-phase supercooling method in a hydrogen atmosphere using Ga as a solvent. 3 g of Ga melt, 1 g of GaAs source, and 0.015 g of Si as an impurity were added. The growth conditions were a saturation temperature of 600°C, an initial supersaturation of 0.8°C, an average cooling rate of 0.3°C/min, and a growth time of 60 minutes. As a result, a liquid-phase grown single crystal layer with a horizontal growth width of 100 μm, a vertical growth width of 10 μm, and a mirror-surfaced upper surface was obtained.

(Example 2) The same method as in Example 1 was used except that the average cooling rate was 0.1° C./min and the growth rate was 60 minutes. As a result, the horizontal growth width was 120
A liquid phase grown single crystal layer with a mirror surface on the upper surface and a vertical growth width of 15 μm was obtained.

(Comparative Example 1) When growing a single crystal by the liquid phase growth method, the same method as in Example 1 was used except that no impurities were added. As a result, the horizontal growth width was 35
A liquid phase grown single crystal layer with a mirror surface on the upper surface and a vertical growth width of 30 μm was obtained.

(Comparative Example 2) A single crystal was grown using the liquid phase growth method in exactly the same manner as in Example 2, except that no impurities were added. As a result, the horizontal growth width was 40 μm.
A liquid phase grown single crystal layer with a vertical growth width of 25 μm and a mirror surface on the upper surface was obtained.

[0016]

[Effects of the Invention] As mentioned above, when manufacturing a device by growing a single crystal material by the liquid phase growth method via a single crystal material deposited on a single crystal substrate, impurities are added to the solution. Since the growth rate in the vertical direction is suppressed and the growth rate in the horizontal direction is promoted, it is possible to obtain a large area single crystal layer with a small amount of growth. In addition, since it is possible to grow a large amount in the vertical direction, when forming a liquid phase growth layer of a predetermined area, it is possible to reduce the number and area of windows in the mask layer. Therefore, it is not affected by a vapor-phase grown layer having misfit dislocations due to lattice mismatch. Therefore, according to the manufacturing method of the present invention, a heterostructure semiconductor layer made of a single crystal material can be deposited on a single crystal substrate over a large area with a low dislocation density, and a high quality device can be provided.

[Brief explanation of the drawing]

[Figure 1]

[Explanation of symbols]

FIG. 1 is a perspective view of a device according to Example 1 of the present invention, and its entire surface shows a cross section. 1; Single crystal substrate 2; Single crystal material vapor phase growth layer 3; Mask layer 4; Window 5; Single crystal material liquid phase growth layer V; Vertical direction H; Horizontal direction

Claims (1)

[Claims] 1. A step of depositing a single crystal material on a single crystal substrate by a vapor phase growth method, a step of depositing a mask layer with a window on the surface of the single crystal material, and a step of depositing a mask layer with a window on the surface of the single crystal material, and a step of depositing a window in the mask layer by a liquid phase growth method. A method for manufacturing an element comprising a step of growing a single crystal substance from a liquid, the method comprising adding an impurity to the solution when growing the single crystal substance by the liquid phase growth method.