[10p-Z04-1~17] 13.7 Compound and power electron devices and process technology

[10p-Z04-15] Open spaces in TEOS-SiO₂ film deposited on GaN probed by means of positron annihilation

〇Akira Uedono¹, Wataru Ueno¹, Takuji Hosoi², Werner Egger³, Christoph Hugenschmidt³, Marcel Dickmann⁴, Heiji Watanabe² (1.Univ. of Tsukuba, 2.Osaka Univ., 3.UniBwM, 4.TUM)

Keywords:GaN, SiO2, defect

Open spaces in SiO₂ films deposited on GaN were probed by positron annihilation. The films were fabricated on GaN substrates by using plasma chemical vapor deposition. Vacancy-type defects were introduced into the GaN substrate after 1000°C annealing in O₂ atmosphere due to the diffusion of Ga from the substrate to the SiO₂ film. No out-diffusion of Ga into the SiO₂ film was observed for the annealing in N₂ atmosphere. Thus, the observed out-diffusion of Ga was attributed to the enhanced oxidation of GaN during the annealing in O₂ atmosphere.