Interactions between nitrogen, hydrogen, and gallium vacancies in GaAs1ÀxNx alloys
نویسندگان
چکیده
The effects of H on the interaction between Ga vacancies VGa and N in GaAs12xNx dilute alloys are studied through first-principles total-energy calculations. We find that N binds to Ga vacancies and that in the presence of H this binding is enhanced. The formation energy of VGa bonded to N and H ~resulting in a N-H-VGa complex! can be more than 2 eV lower than that of the isolated Ga vacancy VGa in GaAs. Our finding that the concentration of VGa increases with N and even more in the presence of H allows us to interpret several recent experiments.
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