Low specific on-resistance GaN-based vertical heterostructure field effect transistors with nonuniform doping superjunctions
Mao Wei1, Wang Hai-Yong1, Shi Peng-Hao1, Wang Xiao-Fei2, †, Du Ming1, Zheng Xue-Feng1, Wang Chong1, Ma Xiao-Hua1, Zhang Jin-Cheng1, Hao Yue1
       

(color online) A feasible process approach of the proposed non-SJ HFET, showing (a) (N1 doping and H1 thickness) p-type GaN layer growth, (b) trench-1 etching, (c) n-type GaN layer regrowth in trench-1, (d) (N2 doping and H2–H1 thickness) p-type GaN layer growth, (e) trench-2 etching, (f) n-type GaN layer regrowth in trench-2, (g) (N2 doping and H1 thickness) ptype GaN layer and CBL growth, (h) trench-3 etching, (i) n-type GaN layer regrowth in trench-3, and (j) completed device.