| 摘要 |
PURPOSE:To provide a photoconductive device in which a long wave length light scattering in Pbo films is reduced and photoconductive films with high resolutions are provided without deteriorating other characteristics by providing a long wavelength light absorbing region near a light incident side surface. CONSTITUTION:The 1st layers 3-5 of Pbo are formed by evaporation of Pbo. Then S1 doping is carried out with hydride gas such as H2S or H2Se. At that time, high concentration S is contained in the backside surface 5 of the 1st layers by the S1 doping and the optical firbidden band width of that part is narrower than the optical forbidden band width of the conventional film formed by evaporation without the S1 doping. This region 5 performs as a long wavelength light absorbing region. After the S1 doping is carried out, the 2nd layers 6-8 of Pbo are formed. Then doping is carried out with hydride gas such as H2S or H2Se in the same way as the S1 doping. This process is called S2 doping. The region 7 which is doped by the S2 doping maintains the balance of the electric field distribution in the film and, moreover, plays the role of absorbing the long wavelength light component which is not absorbed by the S1 doping region 5. However, the resolution can be sufficiently improved by the S1 doping only.
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