Doping of AlxGa12xN
نویسندگان
چکیده
N-type AlxGa12xN exhibits a dramatic decrease in the free-carrier concentration for x>0.40. Based on first-principles calculations, we propose that two effects are responsible for this behavior: ~i! in the case of doping with oxygen ~the most common unintentional donor!, a DX transition occurs, which converts the shallow donor into a deep level; and ~ii! compensation by the cation vacancy (VGa or VAl), a triple acceptor, increases with alloy composition x . For p-type doping, the calculations indicate that the doping efficiency decreases due to compensation by the nitrogen vacancy. In addition, an increase in the acceptor ionization energy is found with increasing x . @S0003-6951~98!03504-9#
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