METHOD OF GROWING AlN MONOCRYSTAL AND APPARATUS FOR REALISING SAID METHOD Russian patent published in 2012 - IPC C30B23/00 C30B29/38 

FIELD: chemistry.

SUBSTANCE: in the method of growing an AlN monocrystal via gaseous-phase epitaxy from a mixture containing an Al and NH₃ source, involving placing an Al source and a substrate opposite each other in a growth chamber to form a growth zone, the growth surface of said substrate facing said Al source, generating in the growth zone a stream of NH₃, heating the Al source and the substrate to temperatures which facilitate growth of an AlN monocrystal on the substrate; the Al source used is free Al only; the substrate is pre-treated with Ga and/or In, after which the Al source is cooled to 800-900°C and the substrate is annealed by heating to 1300°C-1400°C and subsequently cooling to nitridation temperature of its growth surface; after cooling the substrate to nitridation temperature of its growth surface, NH₃ is fed into the growth zone for 8-15 minutes, and temperature of the Al source is then raised and together with NH₃, Al vapour is fed into the growth zone; at the initial growth phase before reaching thickness of 1-10 mcm, the AlN monocrystal is grown at a rate of not more than 10 mcm/h, and the growth rate is then increased to 100-200 mcm/h. The apparatus for realising this method includes a vacuum chamber, having a housing 1, a growth zone heater 2, a substrate 4 holder 3, crucible 5 for holding the Al source 6 and an Al source 6 heater 7; the crucible 5 for holding the Al source 6 is in form of a container with a toroidal shape which is open on the side of the growth zone, placed inside a shielding chamber 10 provided with a cover 17, said shielding chamber lying in the lower part of the housing 1 and linked to a NH₃ source, wherein there is an opening 13 in the cover of the shielding chamber 10 opposite the central opening of he crucible 5 and the Al source 6.

EFFECT: fewer defects in the grown AlN monocrystal.

4 cl, 3 dwg