PURPOSE: To form an always satisfactory thin film on a cylindrical substrate by providing the substrate and counter electrode in a vacuum reaction vessel, depositing the thin film on the substrate by glow discharge and renewing the counter electrode when the thin film sticking to the counter electrode attains a specific thickness.
CONSTITUTION: The cylindrical substrate 1 for an electrophotographic sensitive body is placed on a supporting jig in the vacuum reaction vessel 5 and is heated to the prescribed temp. by a heater 3. The inside of the vessel 5 is evacuted through a discharge port 7 and a geseous raw material contg. silicon is introduced through an introducing port 6 into the vessel and is adjusted to about 10-2W10 Torr pressure. A DC voltage is impressed in this state between the counter electrode 2 and the substrate 1 by a power source 4 to execute glow discharge so that the thin film is deposited on the substrate 1. The electrode 2 is renewed when the thickness of the thin film sticking to the electrode 2 attains ≥2μ in this operation. The condition of the plasma is thus uniformly maintained and the uniform film thickness distribution is obtd.
HORIUCHI HIROSHI
SATO YOSHIHARU
