两步合金法制作p-GaN高反电极  

Ohmic contacts of high reflective poles on p-GaN using two-step anneal method

作　　者：郭德博[1] 梁萌[1] 范曼宁[1] 刘志强[1] 王良臣[1] 王国宏[1] 

机构地区：[1]中国科学院半导体研究所,北京100083

出　　处：《光电子．激光》2008年第7期902-904,共3页Journal of Optoelectronics·Laser

摘　　要：利用两步合金法获得了能与p-GaN形成良好欧姆接触的高反射电极。电极的构成采用透明电极+高反射金属方案,厚的Ag层或Al层覆盖在合金后的Ni/Au上以提高电极的反射率,以Pt和Au作为覆盖层,可有效地防止Ag的氧化和团聚,短时间的热处理有助于Ag基电极反射率的提高。可靠性测试表明Ag基电极的稳定性较好,对于Al基电极,热处理后反射镜上出现暗斑,导致其反射率的下降。最终获得了波长在460nm处反射率为74%的Ag基高反射电极。We report a thermally stable and highly reflective ohmic contact on p-GaN using high reflective metal overlayer on a thin oxidized Ni/Au bilayer.The conglomerate and oxidation of Ag film under high temperature are eliminated by introducing Pt/Au cladding layers.After annealing at 450 ℃ for 2 h in N2 ambient,Ag-based contacts show better thermal stability than Al-based one.The light reflectance of the Ni/Au/Ni/Ag/Pt/Au multilayer on p-GaN is measured to be about 74% at 460 nm.

关 键 词：P型GAN 欧姆接触 两步合金法 高反射电极 

分 类 号：TN312.8[电子电信—物理电子学]