| 摘要 |
PURPOSE:To provide photosensitivity to an amorphous silicon receptor at both positive and negative polarities and increase the dark volume resistivity by adding oxygen, hydrogen and an impurity selected from the IIIb group of the periodic table to the receptor. CONSTITUTION:Amorphous silicon formed by a glow discharge decomposition method and contg. about 5 10<-2>-10<-5>atomic% oxygen, about 10-40atomic% hydrogen and an about 200-20,000ppm impurity selected from the IIIb group of the periodic table, especially boron is used as a photoconductor layer. When hydrogen is added as a carrier gas for SiH4, it combines with a dangling bond to enable to control the electrical conductivity, yet the dark resistivity is low. By further adding oxygen, the dark resistivity is enhanced remarkably. Since a higher oxygen content deteriorates the photoconductivity, oxygen is added in said range. In the figure, A, B and C show the characteristics of amorphous silicon contg. no oxygen, 10<-5>atomic% oxygen and 10<-2>atomic% oxygen, respectively. |
