Title :
Trapping effects and microwave power performance in AlGaN/GaN HEMTs
Author :
Binari, Steven C. ; Ikossi, Kiki ; Roussos, Jason A. ; Kruppa, Walter ; Park, Doewon ; Dietrich, Harry B. ; Koleske, Daniel D. ; Wickenden, Alma E. ; Henry, Richard L.
Author_Institution :
Naval Res. Lab., Washington, DC, USA
fDate :
3/1/2001 12:00:00 AM
Abstract :
The dc small-signal, and microwave power output characteristics of AlGaN/GaN HEMTs are presented. A maximum drain current greater than 1 A/mm and a gate-drain breakdown voltage over 80 V have been attained. For a 0.4 μm gate length, an fT of 30 GHz and an fmax of 70 GHz have been demonstrated. Trapping effects, attributed to surface and buffer layers, and their relationship to microwave power performance are discussed. It is demonstrated that gate lag is related to surface trapping and drain current collapse is associated with the properties of the GaN buffer layer. Through a reduction of these trapping effects, a CW power density of 3.3 W/mm and a pulsed power density of 6.7 W/mm have been achieved at 3.8 GHz
Keywords :
III-V semiconductors; aluminium compounds; electron traps; gallium compounds; microwave field effect transistors; microwave power transistors; power HEMT; semiconductor device breakdown; 0.4 micron; 3.8 GHz; 30 GHz; 70 GHz; AlGaN-GaN; CW power density; HEMTs; III-V semiconductors; buffer layers; dc small-signal characteristics; drain current collapse; gate lag; gate length; gate-drain breakdown voltage; maximum drain current; microwave power performance; pulsed power density; surface layers; surface trapping; trapping effects; Aluminum gallium nitride; Buffer layers; Doping; Gallium nitride; HEMTs; Heterojunctions; MODFETs; Microwave devices; Microwave transistors; Sheet materials;
Journal_Title :
Electron Devices, IEEE Transactions on
