Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7150187 | Solid-State Electronics | 2018 | 5 Pages |
Abstract
We demonstrated an Au-free ohmic contact for un-doped AlGaN/GaN HEMTs with Ti/Al/Ti/TiW metal structure. The Au-free ohmic contact was fabricated by pre-ohmic recess etching and low annealing temperature. The contact characteristics of the Ti/Al/Ti/TiW Au-free ohmic contacts including current-voltage, contact resistivity, and microstructure are systematically investigated. The contact resistivity of Ti/Al/Ti/TiW ohmic contact with 22-nm recessed depth and 600â¯Â°C annealing temperature is 5.44â¯Ãâ¯10â5â¯Î©â
cm2, which is comparable with conventional Ti/Al/Ni/Au ohmic contact. In addition, the Ti/Al/Ti/TiW ohmic contact shows smooth surface morphology with an excellent surface roughness of 3.69â¯nm. Besides, AlGaN/GaN MISHEMTs based on Ti/Al/Ti/TiW Au-free low temperature ohmic contacts were fabricated and exhibited good DC characteristics. The reported Au-free AlGaN/GaN HEMT fabrication process can be used in standard Si fabs without the risk of contamination.
Keywords
Related Topics
Physical Sciences and Engineering
Engineering
Electrical and Electronic Engineering
Authors
Qixin Li, Quanbin Zhou, Sheng Gao, Xiaoyi Liu, Hong Wang,