Effect of geometry on the sensing mechanism of GaN Schottky barrier diode temperature sensor

Abstract

To realize the in-situ temperature monitoring of power device, three kinds of Schottky barrier diodes (SBDs) are designed to reveal the effect of geometry on the temperature sensitivity. The current-voltage characteristics at different temperature demonstrate that all the circular-, finger-, and 8-finger- SBDs show good rectification. The forward voltage at a specific sub-threshold current level presents good linearity versus temperature. In addition, the deduced sensitivity presents no dependency on the geometry but is determined by the ideality factor and current density. The sensing mechanism of SBD sensor is explained by the thermionic emission model. Those results are beneficial to the design and fabrication of temperature sensor.