JPS5717952A - Electrophotographic receptor - Google Patents

Abstract

PURPOSE:To render a photosensitive layer and a layer to be charged separately designable, and to form a photoreceptor having high sensitivity and high resolution, by sandwiching a photosensitive amorphous silicon layer between silicon type high resistance layers having optical band gaps larger than that of the photosensitive layer. CONSTITUTION:A high resistance layer 7 larger in optical band gap than a photosensitive amorphous silicon hydride layer 6 is formed on the layer 6 using amorphous silicon hydride carbide having 10<13>-10<14>OMEGA.cm resistivity in a nondoped state. A high resistance layer 8 made of the same silicon carbide is also formed under the layer 6 and on a metal electrode 9 to obtain an electrophotographic receptor. A time constant of dark decay can be set to a practicable level by virtue of the resistivity and thickness of the high resistance layers 7, 8 even when the resistivity of the layer 6 is as low as 10<9>-10<8>OMEGA.cm. The layer 7 is made thin to such a degree as not causing dielectric breakdown in a charging step in order to enhance resolution, sensitivity of the layer 6 to a wavelength can be raised by width of the layer 8, so a time constant of dark decay can be designed independent of the layer 6, thus permitting a photoreceptor to be designed and fabricated in accordance with the apparatus using this.