Thermal annealing behaviour of Al/Ni/Au multilayer on n-GaN Schottky contacts

作     者：刘芳 王涛 沈波 黄森 林芳 马楠 许福军 王鹏 姚建铨 

作者机构：College of Precision Instrument and Opto-Electronics Engineering Institute of Laser and Optoelectronics Tianjin University Key Lab of Optoelectric Information Science and Technology of Ministry of Education Tianjin University State Key Laboratory of Artificial Microstructure and Mesoscopic Physics School of Physics Peking University 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2009年第18卷第4期

页      面：1618-1621页

核心收录：

学科分类：080903[工学-微电子学与固体电子学] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 080502[工学-材料学] 

主　　题：Schottky contact barrier height ideality factor thermal annealing 

摘      要：Recently GaN-based high electron mobility transistors （HEMTs） have revealed the superior properties of a high breakdown field and high electron saturation velocity. Reduction of the gate leakage current is one of the key issues to be solved for their further improvement. This paper reports that an Al layer as thin as 3 nm was inserted between the conventional Ni/Au Schottky contact and n-GaN epilayers, and the Schottky behaviour of Al/Ni/Au contact was investigated under various annealing conditions by current-voltage （I-V） measurements. A non-linear fitting method was used to extract the contact parameters from the I-V characteristic curves. Experimental results indicate that reduction of the gate leakage current by as much as four orders of magnitude was successfully recorded by thermal annealing. And high quality Schottky contact with a barrier height of 0.875 eV and the lowest reverse-bias leakage current, respectively, can be obtained under 12 min annealing at 450 ℃ in N2 ambience.