We report experimental and theoretical results for self- aligned gate quantum-well p-channel pseudomorphic GaAs/InGaAs/AlGaAs heterostructure insulated-gate field-effect transistors (HIGFET's). High transconductances and transconductance parameters, 113 mS/mm and 305 mS/mm/V at room temperature for 0.8-µm gate length, are observed. We discuss the effects of built-in strain on the valence bands, and we analyze the device data in terms of a modified charge control model. We present data on the gate length dependence of the device parameters and discuss the subthreshold characteristics and the evidence for implant straggle. We also show the importance of the gate current for the device characteristics and propose to reduce the gate current and thus to increase the voltage swing by fabricating p-channel devices with p-doped InGaAs channels and n+ AlGaAs gates on the insulating AlGaAs layer.
Bibliographical noteFunding Information:
Manuscript received March 23, 1989. This work was supported in part by the Air Force Wright Aeronautical Laboratories, WPAFB, under Contract F33615-86-C-1130. M. Shur received partial support from Honey-well, Inc. and from the Microelectronics and Information Sciences Center at the University of Minnesota. The review of this paper was arranged by Associate Editor S.-S. Pei.