物理学报Issue(12)：1-8,8.DOI:10.7498/aps.63.127302
Ni/Ag/Ti/Au与p-GaN的欧姆接触性能及光反射率
The reflectivity and ohmic contact resistivity of Ni/Ag/Ti/Au in contact with p-GaN
摘要
Abstract
The ohmic reflectivity of Ni/Ag/Ti/Au in contact with p-GaN is studied. It is found that under different thickness values of Ni, different annealing temperatures and different annealing atmospheres, the performances of Ni/Ag/Ti/Au electrode are greatly changed. The contact resistivity is measured using the transmission line model. The reflectivity of the electrode is investigated by using a spectrophotometer. The results reveal that the thinner the Ni metal layer, the higher its reflectivity is, in addition, the thickness value of Ni metal has a little influence on contact resistivity. There appears an abrupt decrease in reflectivity of electrode after annealing at a temperature higher than 400 ◦C. It is noticed that the reflectivity decreases more sharply after annealing in oxygen atmosphere than in nitrogen atmosphere. However, annealing in oxygen atmosphere is more helpful to reduce the contact resistivity. The comprehensive evaluations of the contact resistivity and reflectivity indicate that the better performances of Ni (1 nm)/Ag/Ti/Au electrode after rapid annealing in oxygen atmosphere at 400 ◦C are achieved: its contact resistance reaches 5.5 × 10-3 Ω·cm2 and reflectivity rises up to 85%at 450 nm. Light emitting diode (LED) of vertical structure is fabricated with an optimal electrode. The LED under an injection current of 350 mA can achieve the following working parameters: the working voltage is 3.2 V, the optical output power is 270 mW, and the electro-optical conversion efficiency is 24%.关键词
p-GaN/欧姆接触/反射率/快速退火Key words
p-GaN/ohmic contact/reflectivity/rapidly thermal annealing引用本文复制引用
黄亚平,刘硕,云峰,丁文,王越,王宏,赵宇坤,张烨,郭茂峰,侯洵..Ni/Ag/Ti/Au与p-GaN的欧姆接触性能及光反射率[J].物理学报,2014,(12):1-8,8.基金项目
国家高技术研究发展计划(批准号:2012AA041004,2011AA03A111)资助的课题.* Project supported by the National High Technology Research and Development Program of China (Grant Nos.2012AA041004,2011AA03A111) （批准号:2012AA041004,2011AA03A111）
