dc and microwave characteristics of a high current double interface GaAs/InGaAs/AlGaAs pseudomorphic modulation-doped field-effect transistor

Publisher Website
Google Scholar
Abstract
Extremely large current double interface GaAs/In0.15 Ga0.85 As/Al0.15 Ga0.85 As pseudomorphic modulation‐doped field‐effect transistors (MODFET’s) grown by molecular beam epitaxy were achieved. The 1‐μm gate devices studied have peak current levels (430 mA/mm at 300 K and 483 mA/mm at 77 K) roughly one and a half to two times that found in single interface pseudomorphic MODFET’s. These devices also retain high transconductances over a broad range of gate voltage, peaking at 312 mS/mm at 300 K and 362 mS/mm at 77 K. Further, excellent microwave performance is also obtained with a maximum frequency of oscillation ( fmax) of 37 GHz and a current gain cut‐off frequency of as high as 23 GHz at 300 K. An output power level of 14 dBm (1 dB gain compression) was obtained at 6 GHz for a 290‐μm gate width. This double interface single quantum well MODFET may be of great importance in millimeter wave power amplifiers.