Comparison of hot spot temperature between Si and SiC power MOSFET using electro-thermal analysis

Abstract

Recently, thermal problem of electronics is becoming more serious, because electronic devices have been downsizing. Especially, since very high electrical field generates in power devices, it is possible that nano-micro scale high temperature hot spots appear in the device. The hot spot temperature has an impact on performance of electronics, and the hot spot has potential of malfunctioning of the device. Therefore, for higher reliability of electronics, accurate thermal design considering nano-micro scale hot spot is important. In recent years, SiC power semiconductor devices are receiving attention as high-voltage semiconductor devices. For accurate thermal design of the SiC power semiconductor devices, accurate thermal properties of SiC power semiconductor devices should be obtained. However, details of thermal properties of SiC device are not clear. Since high electric field generates in power semiconductor devices, energy non-equilibrium state between electron and lattice should be considered to investigate the hot spot, and Electro-Thermal Analysis is attractive to deal with this non-equilibrium state. In this paper, thermal properties of SiC power semiconductor device are discussed using Electro-Thermal Analysis. We focus on heat generation and hot spot temperature of SiC power MOSFET. By comparing thermal properties of Si power MOSFET with that of SiC power MOSFET, difference of thermal properties between these two MOSFETs is discussed.