THERMAL ANNEALING EFFECTS ON P-TYPE MG-DOPED GAN FILMS

Low-resistivity p-type GaN films were obtained by N2-ambient thermal annealing at temperatures above 700-degrees-C or the first time. Before thermal annealing, the resistivity of Mg-doped GaN films was approximately 1 x 10(6) OMEGA.cm. After thermal annealing at temperatures above 700-degrees-C, the resistivity, hole carrier concentration and hole mobility became 2-OMEGA.cm, 3 x 10(17)/cm3 and 10 cm2/V.s, respectively. In photoluminescence measurements, the intensity of 750-nm deep-level emissions (DL emissions) sharply decreased upon thermal annealing at temperatures above 700-degrees-C, as did the change in resistivity, and 450-nm blue emissions showed maximum intensity at approximately 700-degrees-C of thermal annealing.