Selenium, Silicon and SiC power diodes as temperature sensors, operated in different voltage regimes and under extreme conditions

Commercial semiconductor temperature sensors are nowadays mostly based on silicon diodes and transistors, operated under constant forward current conditions. We compared the temperature sensing capabilities of a series of different power diodes from different materials not only in the forward, but also in the reverse bias and in one example also in the breakdown voltage regime. All investigated devices, including the historical Se rectifiers, showed stable temperature sensing capabilities in the forward bias regime under moderate temperature changes. Some of them have been tested under extreme conditions like extreme temperatures and particle irradiation. In particular it is shown in the case of SiC Schottky diodes, that the excellent temperature sensing properties are also maintained after irradiation with high doses of high energy ions. In the case of Silicon pn diodes the sensitivity as temperature sensor in the forward voltage and avalanche breakdown regime has been determined. In both regimes the sensors showed very good linear characteristics, when biased under constant current conditions. For Silicon diodes, also the temperature limit, where no irreversible device changes are observed has been determined and the defect creation for higher temperatures has been monitored.