JPS61197498A - Production of single crystal of compound semiconductor - Google Patents

Abstract

PURPOSE:In producing single crystal of III-V group compound semiconductor by pulling it up from a melt solution of raw material by the use of B2O3 as a sealing agent, to produce the single crystal of compound semiconductor by a simple device, by heating the surface of B2O3 of the sealing agent at a specific temperature. CONSTITUTION:In producing single crystal of III-V group compound semiconductor such as GaAs, GaP, InP, etc., a polycrystal of the compound or raw material elements to give a given composition ratio are put in the rotatable crucible 3 in the high-pressure container 1. Then, B2O3 as a sealing agent is put in the crucible, the high-pressure container is filled with an inert gas such as Ar, etc., the crucible 3 is heated by the heater 2, to form the melt layer 7 of the compound and the B2O3 melt layer 8 of the sealing agent on it. The surface of the sealing agent of the B2O3 melt layer 8 is heated >=1,100 deg.C by the heater 9, scum in the melt raw material is vaporized, a given temperature distribution is restored, single crystal is grown on the seed crystal 6 at the tip of the rotary pulling shaft 5 and pulled up.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention uses a hut-V group compound semiconductor single crystal, for example GaAs.
, Gap, Engineering nP, etc.

[Conventional technology]

As a method for manufacturing group (1)-V compound semiconductors, a method of pulling a single crystal from a raw material melt covered with a liquid sealant, the so-called high-pressure sealing pulling method, is known. At this time, B2O3 is generally used as a sealant, but the low temperature of B2O3 prevents the solidification (scum) from vaporizing from the raw materials generated during melting of the raw materials and crystal growth. The crystals adhere to or come into contact with the crystal growth interface, causing twin lineage. As a conventional technique for solving this problem, for example, there is a method of using a double crucible as shown in Japanese Patent Application Laid-Open No. 172290/1983.

By using a double crucible consisting of a crucible and an inner crucible with pores at the bottom, the raw material melt is covered with a sealant (BzOs etc.).
The growth raw material melt and the supply raw material melt are doubled, and the deviation from the chemical equivalence ratio composition of the growth raw material melt and the deviation from the chemical equivalence ratio composition of the supply raw material melt are mutually This method has the advantage that scum generated from polycrystals does not mix into the growth raw material melt. [Problem to be solved by the invention] However, the conventional method of this type as mentioned above The method has the disadvantage that the equipment is quite complex. In addition, there are problems with crucibles with complicated shapes, especially when PBN is used as the crucible, and the cost is extremely high.

It is an object of the present invention to provide a method for easily producing a compound semiconductor single crystal with good reproducibility, without using complicated equipment, and without using any complicated equipment.

[Elaborate means to solve problems]

The present invention provides a method for producing a III-V group compound semiconductor crystal by pulling boron oxide from a raw material melt using boron oxide as a sealing agent, in which the surface temperature of the boron oxide is set to t-1100°C or higher under high pressure, and the AK 1) A method for producing a group V compound semiconductor single crystal, characterized in that crystal growth is performed after vaporizing the surface of the raw material melt and the solidified material in the boron oxide.

The present invention will be explained based on the accompanying drawings. FIG. 1 shows an example of a single crystal manufacturing apparatus by a pulling method, and 1 is a high-pressure vessel, and a crucible 5 is installed in this high-pressure vessel 1.
This crucible is rotatably supported by a support member 4, and heated to a predetermined temperature by a heater 2 provided around the crucible. A pulling shaft 5 having a seed crystal 6 at its tip is provided in the upper part of the crucible 3, and the pulling shaft 5 is configured to rotate and move up and down. A sub-heater 9 is provided on the upper part of the crucible 3. When producing, for example, a GaAs single crystal using the above-mentioned apparatus, gallium (Ga) and arsenic (A8) are placed in the crucible 3 at a ratio that will yield a single crystal with a desired composition ratio. Ru.

Then BzOst is used as a sealant. Once a predetermined amount of Ga, 1B, and Boo@f is injected into the crucible 3, the crucible 3 is placed in the high-pressure container 1, and an inert gas such as argon or nitrogen is injected to create a high pressure of 10 to 50 atm. QG
Heating is performed at a temperature higher than the GaO2 point (approximately 1260° C.).

Then, in the crucible 3, a GaAs melt layer 7 is formed at the bottom, a 320 m melt layer 8 is formed at the top, and this B,
o, the layer acts as a sealant and G! Prevent evaporation of LAII melt. After GaAe is melted, B is 0s in the sub-heater 9.
The surface temperature of the sealant is raised to t-1100° C. or higher to vaporize the scum, and then the temperature is returned to a predetermined temperature distribution and the single crystal is pulled out.

[Effect]

In the present invention, the material inside the melt is completely melted and the G
After forming the aAl3 molten layer 7 and the B 03 molten layer 8'gt, heating is performed using a sub-heater 9 so that the B2O3 surface temperature becomes 1100° C. or higher.

By heating B1Osk in this way, FhOs
The viscosity coefficient of B! decreases, and the temperature of the scum in IhOs also increases.The scum vaporizes, and B! 03
It rises within the layer and disappears by scattering into the inert gas. This can prevent the occurrence of twin lineage, etc.

〔Example〕

Next, examples of the present invention will be described and explained in detail. A 1000ft GaAe polycrystalline crucible made of Pyrolithic poron nitride (
PBN crucible), and the water content is 150 ppm.
After charging 180 liters of BsOs't', place it in a high-pressure container and make the inside of the container 71 x 10-8 torr true 9, then pressurize N and gas to 20 atm, and place it in a crucible "t126".
It was heated to 0° C. to melt the GaAe polycrystalline body and the B layer. When the material in the crucible is completely melted, use the sub-heater and B! 03, B=O, surface temperature t-1150
℃, and the scum on the surface of the melt and in B, O, and the like was removed.

After 1 hour, the heating with the sub-heater was stopped and the single crystal was pulled.9. The number of twin lineages has decreased dramatically, and all the five crystals pulled out are full-length single crystals. It should be noted that the effect of the method of the present invention is remarkable when compared with the conventional method in which twin lineage occurred in 50 to 60 inches of the pulled crystal.

〔Effect of the invention〕

As explained above, the method of the present invention can remove the scum in the surface B and O1 of the group molten liquid without using complicated equipment such as a double crucible.
- Group compound semiconductor single crystal gold can be easily obtained with good reproducibility. It is also effective when producing a long single crystal of 100 m or more.

[Brief explanation of the drawing]

FIG. 1 is a sectional view illustrating one embodiment of the present invention. In the figure, 1 is a high-pressure container, 2 is a heater, 3 is a crucible, 4 is a support, 5 is a pulling shaft, 6 is a seed crystal, 7 is a ■-■ group compound semiconductor raw material melt, and 8 is a B2O3 melt , 9 is a sub-heater.

Claims (1)

[Claims] A method for producing a III-V compound semiconductor single crystal by pulling boron oxide from a raw material melt using boron oxide as a sealing agent, wherein the surface temperature of the boron oxide under high pressure is set to 1100°C or higher; A method for producing a III-V group compound semiconductor single crystal, characterized in that crystal growth is performed after the surface of the raw material melt and the solidified material in the boron oxide are vaporized.