A theoretical study on the linearity of the Id-T curve of a SiC MESFET for sensor application

Abstract

This theoretical study includes the impact of ambient temperature fluctuations on the drain current of a SiC MESFET considering two field regions under the gate at a considerably high drain field. The variations of drain current of the device with ambient temperature are studied and the sensitivity of the device with temperature is calculated. An analytical expression of temperature sensitivity of the device is derived for a MESFET operating under the two region model. The variations of device sensitivity with temperature are presented for different gate length and applied biases. The results show that the linearity of drain current over ambient thermal variation improves for proper biasing conditions of gate and drain terminals and selection of appropriate gate length. Moreover, an effort has been made to compare our work with an experimentally observed data reported earlier.