Title :
Short channel AlGaN/GaN MODFET´s with 50-GHz fT and 1.7-W/mm output-power at 10 GHz
Author :
Wu, Y.-F. ; Keller, B.P. ; Keller, S. ; Nguyen, N.X. ; Le, M. ; Nguyen, C. ; Jenkins, T.J. ; Kehias, L.T. ; DenBaars, S.P. ; Mishra, U.K.
Author_Institution :
Dept. of Electr. & Comput. Eng., California Univ., Santa Barbara, CA, USA
Abstract :
A thin barrier-donor layer of 200 /spl Aring/ was used to increase the active input capacitance and improve the extrinsic current-gain cutoff frequency (fT) of short-gate-length AlGaN/GaN MODFETs. 0.2-μm gate-length devices fabricated on such an epi-structure with sheet carrier density of /spl sim/8×10/sup 12/ cm/sup -2/ and mobility of 1200 cm2/Vs showed a record fT of 50 GHz for GaN based FETs. High channel saturation current and transconductance of 800 mA/mm and 240 mS/mm respectively were also achieved along with breakdown voltages of 80 V per μm gate-drain spacing. These excellent characteristics translated into a CW output power density of 1.7 W/mm at 10 GHz, exceeding previous record for a solid-state HEMT.
Keywords :
III-V semiconductors; aluminium compounds; capacitance; carrier density; electric breakdown; gallium compounds; microwave field effect transistors; microwave power transistors; power HEMT; power field effect transistors; 0.2 micron; 10 GHz; 240 mS/mm; 50 GHz; AlGaN-GaN; CW output power density; HEMT; active input capacitance; breakdown voltages; channel saturation current; epi-structure; extrinsic current-gain cutoff frequency; short channel MODFET; thin barrier-donor layer; transconductance; Aluminum gallium nitride; Capacitance; Charge carrier density; Cutoff frequency; FETs; Gallium nitride; HEMTs; MODFETs; Power generation; Transconductance;
Journal_Title :
Electron Device Letters, IEEE
