抄録
The optical and electrical properties of evaporated CdS film were measured. The optical properties are similar to those of the single crystal, that is, the absorption edge lies at 2.4 eV; the photosensitivity peaks near the edge; with temperature decrease, the absorption edge and photosensitivity maximum shift towards shorter wave length; while the electrical properties show wide variation from sample to sample and by heat treatment. The photoresponse shows large dependence on the temperature and is closely related with the dark conductivity. By baking in the air, the conductivity at room temperature decreases by a great deal and the activation energy increases. By baking in the reduced atmosphere, the conductivity, the activation energy and photoresponse almost restore their initial values. In this process, the adsorption or desorption of oxygen on the surfaces of microcrystals plays an important role. The bimolecular recombination argument for the interpretation of spectral sensitivity curves seems inadequate.