Hexagonal GaN films were grown onto AlAs nucleation layers by using radio-frequency plasma source-assisted molecular beam epitaxy and GaAs (001) substrates. Transmission electron microscopic results showed that the (00•1) planes of hexagonal GaN were parallel to the (001) planes of the GaAs substrate. Many defects, including stacking faults and dislocations, served to relax misfit strains between the GaN film and the AlAs layer. The stacking faults lay on (00•1) planes, with a Burgers vector of 1/3<1¯1•0>-type. The dislocations were of screw-type, with Burgers vectors of [00•1]-type. The defects had a higher density near to the interface, and a lower density away from the interface.

Transmission Electron Microscopy Study of Hexagonal GaN Film Grown on GaAs(001) Substrate by Using AlAs Nucleation Layer. L.Wan, X.F.Duan, H.Chen, H.Liu, Z.Li, Q.Huang, J.M.Zhou: Journal of Crystal Growth, 2000, 220[4], 379-83