METHOD OF PRODUCING GALLIUM ARSENIDE (GAAS) MONOCRYSTALS Russian patent published in 2024 - IPC C30B29/42 C30B27/02 C30B15/00 

FIELD: chemical or physical processes; electronics.

SUBSTANCE: first, gallium and arsenic are placed in a crucible with excess arsenic from 0.05 to 0.09% of the weight of its stoichiometric amount, and boric anhydride containing 1.0–2.5 wt.% is placed on them. water. Then pressure of inert gas or nitrogen in growth chamber with crucible placed in it is set to 6.0 MPa. Crucible is heated to 850–950 °C at a rate of not less than 5 °C/min and not more than 10 °C/min, this temperature of the crucible is maintained for not less than 30 minutes and not more than 60 minutes, and gallium arsenide is obtained. After that, the crucible is heated to 1,225–1,350 °C at a rate of not less than 5 °C/min and not more than 10 °C/min and a molten gallium arsenide is obtained. Then nitrogen pressure is reduced to 0.2–0.3 MPa for 50–60 minutes. Seed is lowered into gallium arsenide melt and the gallium arsenide monocrystal is drawn by the Czochralski method with liquid sealing of the melt with boric anhydride, providing the crucible rotation speed of 1.5–2.5 rpm, and the seed rotation speed of 2.0–5.0 rpm. Seed displacement is increased from 3.0 mm/h to 8.0 mm/h at the end of monocrystal growth.

EFFECT: invention provides the technical result consisting in reduction of impurities in the obtained gallium arsenide monocrystal.

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