Title :
AlGaN/GaN MODFETs with low ohmic contact resistances by source/drain n+ re-growth
Author :
Wu, Y.F. ; Kapolnek, D. ; Kozodoy, P. ; Thibeault, B. ; Keller, S. ; Keller, B.P. ; DenBaars, S.P. ; Mishra, U.K.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Santa Barbara, CA, USA
Abstract :
n+ regrown source-drain regions have been used for AlGaN/GaN MODFETs to obtain a low-resistance ohmic contact and clear-cut ohmic boundaries which will potentially facilitate fabrication of deep submicron-gate devices. The process consists: 1. Formation of the SiO 2 re-growth mask by E-beam evaporation and lift-off; 2. Removal of the AlGaN layer in the ohmic region by RIE; 3. n+ GaN re-growth in the MOCVD reactor; 4. Ohmic metal deposition and annealing. A transfer ohmic contact resistance of 0.44 Ω-mm was achieved. Much improved device performance was obtained with the new ohmic scheme over the conventional scheme with the same metalisation
Keywords :
III-V semiconductors; aluminium compounds; contact resistance; gallium compounds; high electron mobility transistors; ohmic contacts; semiconductor device metallisation; AlGaN-GaN; AlGaN/GaN MODFET; MOCVD; RIE; SiO2 mask; annealing; deep submicron gate device; e-beam evaporation; fabrication; lift-off; metallisation; ohmic boundary; ohmic contact resistance; ohmic metal deposition; source/drain n+ regrowth; Aluminum gallium nitride; Annealing; Contact resistance; Fabrication; Gallium nitride; HEMTs; Inductors; MOCVD; MODFETs; Ohmic contacts;
Conference_Titel :
Compound Semiconductors, 1997 IEEE International Symposium on
Conference_Location :
San Diego, CA
Print_ISBN :
0-7503-0556-8
DOI :
10.1109/ISCS.1998.711683
