Comparative Studies on Double -Doped Al0.3Ga0.7As/InxGa1−xAs/GaAs Symmetrically Graded Doped-Channel Field-Effect Transistors

This work provides comparative studies of a double -doped Al0.3Ga0.7As/InxGa1−xAs/GaAs symmetrically graded x = 0.15 → 0.2 → 0.15 doped-channel field-effect transistor DD-DCFET with respect to a conventional double -doped pseudomorphic high electron mobility transistor pHEMT and a conventional DCFET structure. All threes samples, grown by the low-pressure metallorganic chemical vapor deposition LP-MOCVD system, have identical layer structures except for their different doping schemes. Comprehensive investigations on the static, microwave, and temperature-dependent characteristics have been made. Possessing the advantages of DCFETs and pHEMTs, the proposed DD-DCFET has demonstrated comprehensively superior linearity, current drive, voltage gain, high-frequency characteristics, and thermal stability characteristics. It is promisingly suitable for millimeter-wave integrated circuit applications. © 2007 The Electrochemical Society. DOI: 10.1149/1.2711079 All rights reserved.