Influence factors and temperature reliability of ohmic contact on AlGaN/GaN HEMTs

Autor: Liang Song, Kai Fu, Jie Zhao, Guohao Yu, Ronghui Hao, Xiaodong Zhang, Fu Chen, Yaming Fan, Yong Cai, Baoshun Zhang
Jazyk: angličtina
Rok vydání: 2018
Předmět:
Zdroj: AIP Advances, Vol 8, Iss 3, Pp 035213-035213-6 (2018)
Druh dokumentu: article
ISSN: 2158-3226
DOI: 10.1063/1.5024803
Popis: In this paper, we have studied the performance of Ti/Al/Ni/Au ohmic contact with different Al and Au thicknesses and pretreatments. The temperature dependence of contact resistances (Rc) was investigated and it shows that there are different optimal annealing temperatures with different metal thicknesses and pretreatments. The optimal annealing temperature is affected by Al and Au thickness and AlGaN thickness. The etched AlGaN barrier is useful to achieve good ohmic contact (0.24 Ω·mm) with a low annealing temperature. Only the contact resistances of the samples with 130 nm Al layer kept stable and the contact resistances of the samples with 100nm and 160 nm Al layers increased with the measurement temperatures. The contact resistances showed a similar increase and then keep stable trend for all the samples in the long-term 400 °C aging process. The ohmic metal of 20/130/50/50 nm Ti/Al/Ni/Au with ICP etching is the superior candidate considering the contact resistance and reliability.
Databáze: Directory of Open Access Journals