Title :
High-power polarization-engineered GaN/AlGaN/GaN HEMTs without surface passivation
Author :
Shen, L. ; Coffie, R. ; Buttari, D. ; Heikman, S. ; Chakraborty, A. ; Chini, A. ; Keller, S. ; DenBaars, S.P. ; Mishra, U.K.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of California, Santa Barbara, CA, USA
Abstract :
In this paper, a high-power GaN/AlGaN/GaN high electron mobility transistor (HEMT) has been demonstrated. A thick cap layer has been used to screen surface states and reduce dispersion. A deep gate recess was used to achieve the desired transconductance. A thin SiO2 layer was deposited on the drain side of the gate recess in order to reduce gate leakage current and improve breakdown voltage. No surface passivation layer was used. A breakdown voltage of 90 V was achieved. A record output power density of 12 W/mm with an associated power-added efficiency (PAE) of 40.5% was measured at 10 GHz. These results demonstrate the potential of the technique as a controllable and repeatable solution to decrease dispersion and produce power from GaN-based HEMTs without surface passivation.
Keywords :
III-V semiconductors; aluminium compounds; gallium compounds; leakage currents; passivation; power HEMT; semiconductor device breakdown; SiO; breakdown voltage; deep gate recess; deposition; dispersion reduction; drain gate recess; gate leakage current reduction; high electron mobility transistor; high-power polarization-engineered HEMTs; output power density; power reduction; power-added efficiency; screen surface states; surface passivation; transconductance; Aluminum gallium nitride; Density measurement; Gallium nitride; HEMTs; Leakage current; MODFETs; Passivation; Polarization; Power generation; Transconductance;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2003.821673