Interface morphology, chemistry and dislocation structures of wafer-bonded compound semiconductors

Abstract

The interface morphology, chemistry and dislocation structures of a few typical wafer-bonded compound semiconductors were characterized. The relations between the interface dislocation structures and electrical performances were discussed. The interface chemistry of these semiconductors was analysed by using electron energy loss spectra. In general, different wafer annealing conditions could result in varied interface crystalline to amorphous real ratios. It has been found that the interface oxides start to segregate and form the scattered interface amorphous nanoinclusions upon wafer thermal annealing. A mismatched wafer-bonded heterointerface is accommodated by the elastic strain relief through the combination of Lomer edge dislocations and interface amorphous nanoinclusions. Different annealing temperatures may result in different morphologies and oxygen concentrations of the nanoinclusions. It is believed that the formation of these interface nanoinclusions with possibly highly concentrated oxygen is a result of the interface atomic diffusion and oxide relocation processes.