Diode temperature sensor with the output voltage proportional to the absolute temperature and its application to the thin film Pirani Vacuum Sensor

摘要

It is demonstrated that our proposed new type temperature sensor has a proportional output signal voltage ΔV to the absolute temperature T as our theoretically predicted equation ΔV=αT by choosing the proper constant dc current I{sub}0, where T is the absolute temperature and α a constant. In these experiments square waveform as an ac small signal current δI superimposed on the I{sub}0 is adopted and δI/I{sub}0 is kept constant against the source voltage fluctuation. As results the good proportional relationships between ΔV and T over the temperature range of 77-470K and 140-500K for the Si pn diode and the SiC Schottky diode, respectively, are achieved. This new temperature sensor is applied to the thin film Pirani vacuum sensor proposed by us to measure the temperature difference between temperatures by double pulse heating of a cantilever using a diode-heater driven by different constant forward voltages. This prototype vacuum sensor is sensitive in the very wide vacuum pressure range of 1×10{sup}(-2) - 10{sup}5 Pa at least.