JPH0789799A - Production of in-containing iii-v compound semiconductor crystal - Google Patents

Abstract

PURPOSE:To produce an In-contg. III-V compd. semiconductor crystal almost free from crystal defects by an organometallic vapor growth method at >=600 deg.C growth temp. CONSTITUTION:Starting material for In and starting material for a group V element are alternately fed and vapor growth is carried out within the growth temp. range of 600-800 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an In-based III-V group compound semiconductor crystal such as InAs, InP, InSb, etc., using a metal organic chemical vapor deposition method.

[0002]

2. Description of the Related Art InAs compound semiconductors and Group III elements are I
The In-based III-V group compound semiconductor, which is n, has a characteristic different from that of GaAs and is widely used in various optoelectronic devices. These compound semiconductor crystals were produced by the metal organic chemical vapor deposition method. When InAs is grown, TMI (trimethylindium), TEI (triethylindium) or the like is used as a group III raw material, and AsH ₃ (arsine) or TBA (tertiary butylarsine) or the like is used as a group V raw material at 400 ° C. The raw material was thermally decomposed and grown on the substrate heated to a growth temperature of less than 600 ° C.

When the temperature is lower than 400 ° C. in the above growth temperature range, the thermal decomposition of the raw material does not occur completely, and the crystallinity deteriorates.
Further, at a high temperature of 600 ° C. or higher, a group III raw material (for example, T
The thermal decomposition reaction between the MI) and the group V raw material (for example, AsH ₃ ) occurs in the gas phase before the substrate surface, and the crystallinity also deteriorates.

[0004]

On the other hand, GaAs, Al
To grow a good crystal with few crystal defects in a compound semiconductor such as GaAs or GaP by the metal organic chemical vapor deposition method, 60
Although it has been known that a growth temperature of 0 ° C. or higher is required, the vapor growth of In-based III-V group compound semiconductor crystals could not be performed at a growth temperature of 600 ° C. or higher for the above reason. Therefore, the present invention is intended to provide a method for producing an In-based III-V group compound semiconductor crystal with few crystal defects at a growth temperature of 600 ° C. or higher by using the metal organic chemical vapor deposition method.

[0005]

The present invention is a method for producing an In-based III-V group compound semiconductor crystal, such as InAs, which uses metalorganic vapor phase epitaxy, in which In raw materials and V raw materials are alternately supplied, A method for producing an In-based III-V group compound semiconductor crystal, characterized in that vapor phase growth is performed at a growth temperature in the range of 600 to 800 ° C.

[0006]

FIG. 2 is a diagram showing the sequence of the raw material supply when growing InAs by the conventional metalorganic vapor phase epitaxy. II
Group I raw materials (TMI, TEI, etc.) and Group V raw materials (AsH ₃ ,
(TBA, etc.) is simultaneously flown onto the substrate for vapor phase growth. This method is different from Ga-based or Al-based organometallics, and in In-based raw materials, when the growth temperature is raised to 600 ° C. or higher, a thermal decomposition reaction occurs before the substrate, so that a good crystal is grown on the substrate. I couldn't do it.

FIG. 1 is a diagram showing a raw material supply sequence according to the present invention, in which a group III raw material and a group V raw material are alternately flowed, and a time during which only hydrogen is flown is provided to mix the raw materials upstream from the substrate. It was possible to prevent this, and it became possible to adopt a high growth temperature of 600 ° C. or higher. as a result,
Similar to GaAs and other crystals, good I with few crystal defects
It has become possible to produce nAs crystals. When the growth temperature exceeds 800 ° C, the grown epitaxial layer begins to decompose and re-evaporate, so the upper limit growth temperature was set to 800 ° C. Although the production of InAs crystals has been described above, it has become possible to obtain good crystals with few crystal defects in the same manner for other In-based III-V group compound semiconductor crystals.

[0008]

【Example】

(Example) An InAs crystal was grown on a GaAs substrate by the growth sequence of FIG. 1 by a metal organic chemical vapor deposition method. The growth temperature was maintained at 650 ° C. Then, the temperature of the bottle containing TMI is maintained at 20 ° C. and the supply flow rate is 100 s.
ccm, and the supply flow rate of AsH _{3 with} a concentration of 10% was adjusted to 50 sccm.
The supply time of I and AsH ₃ was both set to 4 seconds, during which hydrogen was flowed for 2 seconds to maintain the growth pressure at 10 Torr for vapor phase growth. The obtained InAs crystal had a film thickness of 1.5 μm, and the hole mobility at 77K was measured. As a result, the crystal characteristic was 30,000 cm ² / Vs, which was extremely good.

(Comparative Example) An InAs crystal was grown on a GaAs substrate by the growth sequence of FIG. 2 by a metal organic chemical vapor deposition method. Growth temperature is kept at 400 ℃, TMI and A
The vapor phase growth was performed in the same manner as in Example 1 with the supply flow rate of sH ₃ and the growth pressure. The obtained InAs crystal has a film thickness of 1.
When the hole mobility at 77 K was measured at 5 μm, it was 15000 cm ² / Vs.

[0010]

EFFECTS OF THE INVENTION The present invention, by adopting the above-mentioned constitution, enables growth of In-based III-V group compound semiconductor crystals such as InAs having excellent crystallinity by metal organic chemical vapor deposition. did.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a growth sequence of an InAs crystal of the present invention.

FIG. 2 is an explanatory diagram showing a growth sequence of a conventional InAs crystal.

Claims (2)

[Claims] 1. In-based III- using a metal organic chemical vapor deposition method
In the method for producing a Group V compound semiconductor crystal, In raw materials and Group V raw materials are alternately supplied, and the growth temperature is 600 to 800 ° C.
A method for producing an In-based III-V group compound semiconductor crystal, characterized in that vapor-phase growth is performed within the range. 2. The method for producing an In-based III-V compound semiconductor crystal according to claim 1, wherein the V-group element is As.