Preferential regrowth of indium-tin oxide (ITO) films deposited on GaN (0001) by rf-magnetron sputter

Effects of thermal treatments on the electrical properties and microstructu res of indium-tin oxide (ITO)/GaN contacts have been investigated using a r f-magnetron sputter deposition followed by rapid thermal annealing. ITO fil ms annealed at 800 degreesC revealed Schottky contact characteristics with a barrier height corresponding to ITO's work function of 4.62 eV. The evolu tion of electrical properties of ITO/GaN contacts was attributed to the pre ferential regrowth of In2O3 (222)//GaN(0001) with an ideal metal-semiconduc tor Schottky contact. The feasible use of ITO/GaN as a transparent Schottky contact would be realized by the enhanced regrowth of In2O3 at high temper ature.