Investigation of Mg doping in high-Al content p-type AlxGa1-xN (0.3< x <0.5) -: art. no. 082107

A study of Mg doping of AlxGa1-xN up to x similar to 50% using microstructural and electrical probes is reported. The viability of effective p-type doping is defined by a minimum concentration of Mg required to offset the background impurities and, more importantly, a maximum limit above which inversion domains and structural defects start to nucleate, accompanied by a rapid degradation of electrical transport. Resistivity of 10 Omega cm and free hole concentrations above 10(17) cm(-3) are achieved for AlxGa1-xN up to x similar to 50% within an optimum window of Mg incorporation. (c) 2005 American Institute of Physics.