METHOD FOR FORMING POLYCRYSTALLINE HIGHLY DOPED INAS NANOLAYER ON SAPPHIRE SUBSTRATE FOR RADIATION-RESISTANT MAGNETIC FIELD SENSORS Russian patent published in 2022 - IPC B82B3/00 G02F1/17 

FIELD: semiconductor nanoheterostructures.

SUBSTANCE: invention relates to semiconductor nanoheterostructures A_IIIB_V used for the manufacture of radiation-resistant magnetic field sensors. Creation of the lower nucleating InAlAs layer with a thickness of 1÷5 nm, located directly on the sapphire substrate, is necessary for wetting the sapphire surface and preventing surface amorphization during the epitaxial growth of the overlying layers. The annealing of the InAs layer in an arsenic flow for 1÷5 min, which follows the lower seed layer, makes it possible to smooth the surface of the nanolayer, reducing the surface roughness of the heterostructure. The thickness of the lower germ layer is determined, on the one hand, by the need to restore the surface of the sapphire substrate and prevent its amorphization after mandatory preliminary outgassing, and, on the other hand, by preventing mechanical relaxation before the formation of the upper germ layer. The formation of the upper nucleating InAs layer with a thickness of 1÷3 nm followed by annealing in an arsenic flow for 8÷12 minutes leads to the relaxation of mechanical stresses in the layer, as a result of which misfit dislocations appear in the underlying layers of the heterostructure and penetrate to a lesser extent into the highly doped InAs layer, which makes it possible to obtain InAs layers with low resistivity of higher crystalline quality. The presence of a transition layer with a thickness of 1÷3 nm is necessary to avoid conduction along the auxiliary layers under the action of neutron irradiation, including during transmutation doping processes, which can lead to a change in the sensitivity and resistivity of the magnetic field sensor.

EFFECT: obtaining polycrystalline highly doped InAs nanolayers of high crystalline quality on a sapphire substrate with low surface roughness and low resistivity, suitable for creating radiation-resistant magnetic field sensors.

1 cl, 3 dwg