Photodetector for electrophotography and process for its fabrication

摘要

Photodetector for electrophotography comprising a photodetector layer on a conductive substrate. The photodetector layer is constructed in such a way that it has a substantial level width of a forbidden band which width expands gradually from the substrate side in the direction to the surface side. The photodetector layer preferably consists of amorphous silicon. A process for fabricating the photodetector for electrophotography consists in the atoms of at least one of the elements carbon or nitrogen being incorporated as impurities into the amorphous silicon photodetector layer in such a way that the amount of the addition of said atoms increases gradually from the substrate side of the photodetector layer towards the surface side. Thus a photodetector for electrophotography is obtained which can attain a high surface potential and whose photosensitivity does not decrease up to a range of long wavelengths.