THE EFFECT OF THERMAL OXIDATION ON THE PHOTORESPONSE PROPERTIES OF PbSe PHOTODETECTORS

Abstract

In this study, thin PbSe films were deposited on the Si(100) by ion beam sputtering aiming at forming photoconductive infrared detectors. PbSe photodetectors are then gained through thermal oxidation over different temperatures for sensitization. The effect of oxygen sensitization on the morphology, composition and structure of PbSe photodetectors is studied. It was found that during the sensitization, the PbSe thin film grains gradually refine the melting junction due to oxidation and recrystallization. The proportion of the film surface O/(PbSe) atoms increased significantly, while the Se/Pb atoms greatly decreased due to the increased gasification of SeO2. The noise signal for sensitized PbSe films decreased and the detection rates were improved. The sensitization process designed in this paper helps to improve the photoresponse function of PbSe films.