中国物理B ›› 2010, Vol. 19 ›› Issue (12): 127304-127304.doi: 10.1088/1674-1056/19/12/127304
刘新宇1, 魏珂1, 黄俊1, 林芳2, 沈波2, 卢励吾2, 马楠2, 许福军2, 苗振林2, 宋杰2
Lin Fang(林芳)a), Shen Bo(沈波)a)†,Lu Li-Wu(卢励吾)a), Ma Nan(马楠)a), Xu Fu-Jun(许福军)a), Miao Zhen-Lin(苗振林)a), Song Jie(宋杰)a), Liu Xin-Yu(刘新宇)b), Wei Ke(魏珂)b), and Huang Jun(黄俊)b)
摘要: In contrast with Au/Ni/Al0.25Ga0.75N/GaN Schottky contacts, this paper systematically investigates the effect of thermal annealing of Au/Pt/Al0.25Ga0.75N/GaN structures on electrical properties of the two-dimensional electron gas in Al0.25Ga0.75N/GaN heterostructures by means of temperature-dependent Hall and temperature-dependent current–voltage measurements. The two-dimensional electron gas density of the samples with Pt cap layer increases after annealing in N2 ambience at 600 du while the annealing treatment has little effect on the two-dimensional electron gas mobility in comparison with the samples with Ni cap layer. The experimental results indicate that the Au/Pt/Al0.25Ga0.75N/GaN Schottky contacts reduce the reverse leakage current density at high annealing temperatures of 400–600 du. As a conclusion, the better thermal stability of the Au/Pt/Al0.25Ga0.75N/GaN Schottky contacts than the Au/Ni/Al0.25Ga0.75N/GaN Schottky contacts at high temperatures can be attributed to the inertness of the interface between Pt and AlxGa1-xN.
中图分类号: (Surface double layers, Schottky barriers, and work functions)