SURFACE-TREATED ALUMINUM NITRIDE AND ITS PRODUCTION

PROBLEM TO BE SOLVED: To produce a surface-treated aluminum nitride and capable of preventing the oxidation damage and increasing the strength by forming a silica layer on the surface thereof and to provide a method for producing the aluminum nitride. SOLUTION: Oxygen or an oxygen compound gas is reacted with a silicon supply source to provide a silicon oxide gas, which is then deposited on the surface of an aluminum nitride 3 to form a silica layer. The internal temperature of a reactional furnace 1 where the surface treatment of the aluminum nitride 3 is carried out can be regulated with a heat source (not shown in the figure). H2O, O2, CO2, CO and other oxygen-containing gases can be used as a supply source for oxygen and H2, N2, Ar and other gases can be used as a gas for regulating the oxygen partial pressure. Although a mixed gas of H2O with H2 is especially used as an atmospheric gas 7 and fed into the interior of the reactional furnace 1 in the example, the content of the H2O gas is preferably regulated to >=0.05 vol.% by taking the oxygen partial pressure into consideration when the mixed gas of the H2O with H2 is used as the atmospheric gas 7.