PURPOSE: To stabilize performance, to enhance photosensitivity to a longer wavelength side, and to improve durability by forming a light receiving layer composed of the first photoconductive layer made of a-SiGe contg. O in a specified concn. distribution in the layer thickness direction, and the second layer made of a-SiN.
CONSTITUTION: A light receiving layer 104 formed on a substrate 101 consists of the first layer 102 made of a-SiGe and the second layer 103 made of a-SiN. The layer 102 has an layer region O contg. O element in an O concn. C(O), and it has a region X having a C(O) distribution in the layer thickness direction continuously increasing toward the upper surface of the layer 102, and the region O has a region Y below the region X having a C(O) distribution continuously increasing toward the substrate 101. The layer 102 may contain Ge uniformly or not in the layer thickness direction. The layer 102 contains H or halogen element and further, a conductivity governing material, such as an element of group III or V. The use of the light receiving layer made of such a-SiGe(H, X) always stabilizes electrical, optical, and photoconductive characteristics, and it can enhance photosensitive characteristics in the long wavelength region, and improve durability.
OONUKI YUKIHIKO
OONO SHIGERU
