Direct observation of three-dimensional transient temperature distribution in SiC Schottky barrier diode under operation by optical-interference contactless thermometry imaging

Abstract

Abstract We have developed optical-interference contactless thermometry imaging technique to visualize three-dimensional transient temperature distribution in 4H-SiC Schottky barrier diode (SBD) under operation. When a 1 ms forward pulse bias was applied, clear variation of optical interference fringes induced by self-heating and cooling were observed. Thermal diffusion and optical analysis revealed three-dimensional temperature distribution with high spatial (≤10 μm) and temporal (≤100 μs) resolutions. A hot spot that signals breakdown of the SBD was successfully captured as an anomalous interference, which indicated a local heating to a temperature as high as 805 K at the time of failure.