论文信息 - Characterization of oxide precipitates in epitaxial InN by transmission electron microscopy

Characterization of oxide precipitates in epitaxial InN by transmission electron microscopy

InN thin films have been grown epitaxially on GaN-buffered sapphire substrates by molecular-beam epitaxy at 500°C. A high level of oxygen contamination in the growth chamber led to formation of In2O3 precipitates in the films. These precipitates were characterized in detail by transmission electron microscopy (TEM). The concentration of In2O3 was estimated to be less than 0.07vol% in the present samples of oxygen content ∼0.5at.%. Cross-sectional TEM investigations revealed that the precipitates adopt a preferred crystallographic orientation within the InN matrix, and show a characteristic diameter of ∼5nm with average distance of ∼500nm. These observations suggest the effective solubility of O in InN could be below 1at.% at 500°C.

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