Title :
Power and linearity characteristics of field-plated recessed-gate AlGaN-GaN HEMTs
Author :
Chini, A. ; Buttari, D. ; Coffie, R. ; Shen, L. ; Heikman, S. ; Chakraborty, A. ; Keller, S. ; Mishra, U.K.
Author_Institution :
Electr. & Comput. Eng. Dept., Univ. of California, Santa Barbara, CA, USA
fDate :
5/1/2004 12:00:00 AM
Abstract :
Record power density and high-efficiency operation with AlGaN-GaN high-electron mobility transistor (HEMT) devices have been achieved by adopting a field-plated gate-recessed structure. Devices grown on SiC substrate yielded very high power density (18.8 W/mm with 43% power-added efficiency (PAE) as well as high efficiency (74% with 6 W/mm) under single-tone continuous-wave testing at 4 GHz. Devices also showed excellent linearity characteristics when measured under two-tone continuous-wave signals at 4 GHz. When biased in deep-class AB (33 mA/mm, 3% Imax) device maintained a carrier to third-order intermodulation ratio of 30 dBc up to a power level of 2.4 W/mm with 53% PAE; increasing bias current to 66 mA/mm (6% Imax) allowed high linear operation (45 dBc) up to a power level of 1.4 W/mm with 38% PAE.
Keywords :
III-V semiconductors; aluminium compounds; gallium compounds; microwave field effect transistors; power HEMT; 4 GHz; AlGaN-GaN; field-plated gate-recessed structure; high-efficiency mobility transistor; linearity characteristics; microwave power field-effect transistors; power density; power-added efficiency; single-tone continuous-wave testing; third-order intermodulation ratio; two-tone continuous-wave signals; Chemical vapor deposition; FETs; Gallium nitride; HEMTs; Linearity; MODFETs; Microwave devices; Silicon carbide; Substrates; Testing;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2004.826525
