Finite element thermal analysis of localized heating in AlGaN/GaN HEMT based sensors

Abstract

This paper reports the steady-state and transient temperature response of AlGaN/GaN high electron mobility transistor (HEMT) based structures. In this study, three localized heating schemes, namely, continuous self-heating, pulsed self-heating and heating with on-chip heaters are studied for sensor applications that require controlled heating profiles. Two scenarios were considered for the GaN sensor structure: 1) the silicon substrate under the AlGaN/GaN sensor is not removed, and 2) the silicon substrate is removed to form a suspended AlGaN/GaN diaphragm on which the sensor is located. The three heating schemes are analyzed by finite element thermal analysis, evaluated and compared. In addition, general guidelines for designing localized heating architectures for AlGaN/GaN HEMT based sensors are provided.