Two-Dimensional Electron Gas Transport Properties in AlGaN/GaN Heterostructure Field-Effect Transistors

Abstract

This chapter presents both electrical properties and device performance in AlGaN/GaN single- and double-heterostructure field effect transistors (FETs) with in order to understand specific features of the 2DEG transport properties in nitride HFETs. It examines the polarization effects in HFET and their influence on the electrical states in the channel, and provides the details of the channel potential profiles and 2DEG distributions. The chapter highlights the 2DEG transport properties in double-heterostructure FETs where the 2DEG confinement is enhanced due to the enhanced influence of the polarization effects. In the actual device operation, the 2DEG density in an HFET is controlled by the application of gate voltage. Hence, for exploiting and improving device performance, one must understand 2DEG transport properties under the gate voltage application. One advantage of AlGaN/GaN HFETs over GaAs-based and Si devices lies in high potentialities for high-temperature applications.