JPS63142812A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To control an impurity concentration, etc., laterally by forming an insulating film on a substrate, selectively etching the film and the substrate, and then introducing the molecular beam of an impurity for determining a conductivity type to the substrate obliquely with respect to the substrate to perform an MBE (molecular beam epitaxy) growth. CONSTITUTION:After a CVD film 2 of SiO2 is first formed on a whole GaAs substrate 1, the film 2 is selectively etched, the substrate 1 is subsequently selectively etched to form a recess. Then, the etched substrate 1 is mounted in an MBE device, and grown. In this case, when an Si molecular beam and a Be molecular beam are incident from a direction of 180 deg. in a wafer, since the molecular beam of dopant in both p- and n-types are irradiated in the vicinity of the center in the recess, an i-type semiconductor is obtained, but since the molecular beam is masked by the sidewall at the sidewall of the dopant incident direction, p- or n-type semiconductor is obtained. As described above, the substrate is selectively etched to form the recess, and the MBE growth is then executed to simultaneously form p-type, n-type and i-type single crystals laterally.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a method of manufacturing a semiconductor device.

Conventional technology In the manufacture of semiconductor devices, molecular beam epitaxy (MB
E) has good controllability of film thickness and impurity concentration, so MB
Much research and development has been conducted on semiconductor device manufacturing technology using the E method. (For example, Bimolecular Beam Epitaxy Technology, written by Kiyoshi High School, Industrial Research Association, 1984).Hereinafter, a method for manufacturing a semiconductor device using the conventional MBE method as described above will be described with reference to the drawings.

FIG. 2 is a schematic diagram for explaining a conventional method of manufacturing a semiconductor device using the MBE method. In Figure 2, 12
13, 14, 15, 16 are crucibles for Ga, As, Si, and Be, respectively; 17. is a GaAs substrate;
18 is a shutter for a crucible for Si and Be, 19 is a p-type growth layer, 20 is an n-type growth layer, and 21 is a vacuum chamber of the MBE apparatus.

In this manufacturing method, first, Ga with a flat surface is
The A s substrate is placed in the vacuum chamber 21 of the MBE apparatus. When performing Ga As growth, the shutter 1 of the crucible 16 for Be is used at the same time as the crucibles 13 and 14 for Ga and As.
8, p-type GaAs grows.

Next, when the Be shutter 18 is closed and the Si shutter 17 is opened, n-type GaAs grows. In this way, a structure such as a pn junction can be created in the vertical direction (growth direction).

Problems to be Solved by the Invention However, the above configuration has the disadvantage that impurity concentration etc. can only be controlled in the vertical direction (growth direction) and cannot be controlled in the lateral direction (plane direction). had.

In view of the above drawbacks, the present invention provides a method for manufacturing a semiconductor device that allows control of impurity concentration, etc., also in the lateral direction.

Means for Solving the Problems In order to solve the above problems, the method for manufacturing a semiconductor device of the present invention includes a method of manufacturing a semiconductor device using Sio2. After forming an insulating film such as Si3N4 and selectively etching the insulating film and the substrate, MBE growth is performed by making impurity molecular beams that determine the conductivity type obliquely incident on the substrate. has been done.

Effect: With this configuration, in MBE growth, since the molecular beam has a blind propagation property, in the part that becomes a depression due to etching, a region is created where the molecular beam of the impurity between one conductivity type determination is masked by the side wall. , a p-type, n-type, or i-type growth layer can be produced in the lateral direction by one growth.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIG.

FIGS. 1(a) and 1(b) are schematic diagrams for explaining a semiconductor manufacturing method according to an embodiment of the present invention. This example will be explained using GaAs as the semiconductor material. In FIG. 1(,) and FIG. 1(b) showing the same essential part 100, 1 is a GaAs substrate, 2 is a film formed by CVD method such as Sio2, 3 is a GaAs polycrystalline film, 4 to 7 is a crucible that generates molecular beams, and 4 is Ga
5 is for As, 6 is for Si, and 7 is for Be. 8 is a vacuum chamber of the MBE apparatus.

Further, 9, 10, and 11 are p-type, n-type, and i-type growth layers, respectively.

First, a CV of S x O2 is applied to the entire surface of the GaAs substrate 1.
After applying the D film 2, the CVD film 2 is selectively etched, and then the GaAs substrate 1 is selectively etched by several 1100 nanometers.
Etch and make a depression. Next, G a after performing the above processing
The As substrate 1 is placed in an MBE apparatus, and growth is performed.

At this time, when the St molecular beam and the Be molecular beam are incident from a direction of 180 degrees within the wafer plane, the area near the center of the depression is irradiated with both p and n dopant molecular beams, resulting in an i-type semiconductor. On the sidewall in the dopant incident direction, the molecular beam is masked by the sidewall, so it becomes a p- or n-type semiconductor.

As described above, according to this embodiment, by performing MBE growth after forming a depression by selectively etching the substrate,
P-type, n-type, and i-type nest crystals can be formed simultaneously in the lateral direction. By changing the depth and width of the recess, several types of pn junctions can be realized, and just by wiring, light emitting elements,
Light-receiving elements, solar cells, etc. can be created. In addition, by combining with other processes such as diffusion and ion implantation,
It can also be applied to semiconductor integrated circuits.

Further, during growth, an unnecessary GaAs polycrystalline film is deposited on the COD film, but the GaAtz polycrystalline film can be easily removed by HCA or the like.

In this example, both the substrate and the shrimp layer are G a A
s, but InP, AffiGaAs, S
i may be equal.

However, it is necessary to select the type of dopant appropriately depending on the material. Further, the material of the substrate and the epitaxial layer may be different from that of the substrate.

Effects of the Invention As described above, in the present invention, impurities can be controlled in the lateral direction by etching a substrate to form a depression and then performing MBE growth, which has a great practical effect.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram for explaining a method for manufacturing a semiconductor device according to an embodiment of the present invention, and FIG. 2 is a diagram for explaining a conventional method for manufacturing a semiconductor device. 1...G a A ts board, 2...S
i O2,3...G a As polycrystalline film,
9...p-type growth layer, 1o...n-type growth layer, 11...i-type growth layer. Name of agent: Patent attorney Toshio Nakao and one other person
4-(jQ quick) IX'5---As thickness G---3i part ri'y-4 Tomoe part I+ δ--- -Ichiraha Sbu unwritten f3-11 ne tsupo. n-list '1 122/-°-decay←7t<'-

Claims (1)

[Claims] forming a recess on the surface of the semiconductor substrate; making a molecular beam incident on the semiconductor substrate from an oblique direction; masking the molecular beam with the sidewall of the recess; and forming a recess with different properties within the recess; 1. A method for manufacturing a semiconductor device, comprising the step of forming a growth layer.