高平整度GaN HEMT欧姆接触工艺  

A Novel Ohmic Contact Technology for GaN HEMTs

作　　者：陈韬[1] 蒋浩[1] 陈堂胜[1] 

机构地区：[1]南京电子器件研究所,南京210016

出　　处：《固体电子学研究与进展》2015年第4期388-391,共4页Research & Progress of SSE

基　　金：国家03重大专项资助项目(201403003007)

摘　　要：研究了不同金属体系对GaN HEMT欧姆接触表面形貌、击穿电压的影响。研究了不同合金温度以及不同金属体系对接触特性的影响,通过对金属体系结构的优化改善了欧姆接触特性及形貌。采用Ti/Al/Pd/Au(10/200/40/50nm)金属,在750℃合金温度时,得到较低的接触电阻,最小值达到0.18Ω·mm,欧姆接触电极表面粗糙度降低到0.4nm。良好的欧姆接触形貌使GaN HEMT击穿电压提高了10%。通过加速电迁移实验,证明Ti/Al/Pd/Au金属体系可靠性满足工程化需要。A novel GaN Ohmic contact technology was developed and used to improve surface roughness and breakdown voltage of GaN HEMT.It was found that contact resistance could be furtherly reduced by the optimization of the metal structure.With Ti/Al/Pd/Au（10/200/40/50nm）metal structure,a minimum Ohmic contact resistance of 0.18Ω·mm was obtained after750℃ annealing.Using this method,the surface roughness of Ohmic contact metal can be reduced to 0.4nm and the breakdown voltage of GaN HEMT buffer layer can be improved by 10%.The low temperature GaN Ohmic contact technology is promising in the fabrication of high power and high frequency GaN HEMT devices.

关 键 词：氮化镓高电子迁移率晶体管 低温合金 欧姆接触 

分 类 号：TN385[电子电信—物理电子学] TN303