Analysis of a 4H-SiC Lateral PMOSFET Temperature Sensor Between 14 K–482 K

Abstract

A temperature sensor based on a diode-connected 4H-Silicon Carbide p-type metal oxide semiconductor field effect transistor is characterized in the temperature range between 14 K and 482 K and its performance has been analyzed. The study shows that the sensor characteristics are mainly affected by the threshold voltage, but an unusual reduction of the device current is shown for temperatures lower than 76 K, which limits the linearity of the sensor response. Indeed, two operating temperature ranges could be defined. The first one is in the range $ \text{76 K}\leq T \leq \text{175 K}$, showing a linearity of 0.991 in terms of coefficient of determination and a sensitivity of $ \text{6.24 mV/K}$ at a device current of 3.34 nA, instead the second range is for temperatures higher than 175 K with a linearity of 0.986 and a sensitivity of $ \text{66.37 mV/K}$ for a current of 263 nA. Moreover, the device is fully compatible with 4H-SiC CMOS technology making possible its use in integrated circuits.