METHOD OF CHALCOGENISING GaAs SURFACE Russian patent published in 2010 - IPC H01L21/268 

FIELD: chemistry.

SUBSTANCE: method involves chemical treatment and chalcogenisation of the surface of a GaAs plate in an aqueous, alcohol or some other chalcogen-containing solution or ammonium sulphide gas (NH₄)₂S, washing and drying, and vacuum drying the surface of the GaAs plate. After vacuum drying, the chalcogenised surface of the GaAs plate is treated with UV radiation with wavelength λ=172-400 nm and radiation power density W>0.01 W cm^-2 for time t=1-600 seconds in a vacuum at residual atmospheric pressure less than 10^-5 torr. Treatment with UV radiation is carried out at residual atmospheric pressure less than 54·10^-6 torr. A thin metal film or a dielectric film is deposited in the surface of the GaAs plate after treatment with UV radiation.

EFFECT: invention enables activation of desorption of physically adsorbed sulphur, low density of surface states of GaAs, improved electrical parametres of metal-semiconductor contacts and dielectric-semiconductor boundary surface, formed on the chalcogenised GaAs surface.

6 cl, 2 ex, 2 dwg