AlGaN/GaN HEMTs-an overview of device operation and applications

Wide bandgap semiconductors are extremely attractive for the gamut of power electronics applications from power conditioning to microwave transmitters for communications and radar. Of the various materials and device technologies, the AlGaN/GaN high-electron mobility transistor seems the most promising. This paper attempts to present the status of the technology and the market with a view of highlighting both the progress and the remaining problems.

I. Introduction and Market Analysis

As the market for cellular, personal communications services, and broad-band access are expanding and thirdgeneration (3G) mobile systems coming closer to reality, radio frequency (RF) and microwave power amplifiers are beginning to be the focus of attention. A variety of poweramplifier technologies are vying for market share, such as Si lateral-diffused metal–oxide–semiconductors and bipolar transistors, GaAs metal–semiconductor field-effect transistors (MESFETs), GaAs (or GaAs/InGaP) heterojunction bipolar transistors, SiC MESFETs, and GaN high-electron mobility transistors (HEMTs).