PHEMT欧姆接触的双源共蒸技术

The Co-evaporation Technology of Ohmic Contact in GaAs PHEMT

近年来,砷化镓器件的发展极为迅速。其中,欧姆接触的制作是器件研制的关键工艺之一。为了提高GaAsPHEMT器件欧姆接触的性能和可靠性水平,文章比较了三种常见的GaAsPHEMT器件欧姆接触制备技术的差异,分别是:分层蒸发、溅射+蒸发、双源共蒸。通过传输线模型(TLM)法测试数据以及微细形貌分析,得出双源共蒸工艺制备的欧姆接触的电阻率和均匀性综合特性最佳,因此认为双源共蒸技术在大尺寸GaAsPHEMT圆片工艺中具有最优的综合特性。

GaAs PHEMT develps very fast. And one of the most important technology is the ohmic contact performace. In order to improve ohmic contact performance and reliability level of GaAs PHEMT, three different manners to obtain ohmic contacts in GaAs PHEMT are compared in this paper. These manners are layered evaporation, spatter ＆ evaporation and Co-evaporation. Deduced from TLM measurements and SEM observations, the co-evaporation is the better path to form ohmic contact in large size wafer manufactories comprehensively.