In0.52Al0.48As/InxGa1-xAs (0.53<x<1.0) Pseudomorphic High Electron Mobility Transistors with High Breakdown Voltages: Design and Performances

The search for suitable ways to improve the high electron mobility transistors (HEMT's) device performances has stimulated the turbulent research work on pseudomorphic layer structures. Recent interest has been focused on pseudomorphic InAlAs/InGaAs HEMTs. In this paper we report on the design and fabrication of In 0.52 Al 0.48 As/In x Ga 1- x As (0.53<x<1.0) pseudomorphic HEMTs. The main subject of the simulation and experimental work is the design of the channel to allow a maximum InAs molefraction while maintaining excellent device performance. The general results of our investigation are that the current handling capability and the high speed performance improves with x , while the breakdown voltage continuously degrades with increasing x . From our investigation an indium molefraction of x =0.7 was found to be optimum for the high speed performance.