Method for manufacturing electrophotographic photosensitive member
A method for manufacturing an electrophotographic photosensitive member using plasma CVD includes steps of placing a cylindrical base member in a reactor which can be evacuated, the reactor having an electrode therein, so as to be spaced apart from the electrode, introducing a raw material gas for deposited film formation into the reactor, and applying an alternating voltage of a rectangular wave having a frequency in the range of 3 kHz to 300 kHz between the electrode and the cylindrical base member so that a potential at one of the electrode and the cylindrical base member with respect to a potential at the other becomes alternately positive and negative, to decompose the raw material gas, and forming a deposited film on the cylindrical base member. The magnitude of the potential difference between the electrode and the cylindrical base member is selectively controlled.
1. A method for manufacturing an electrophotographic photosensitive member using a plasma CVD method, comprising the steps of:
(i) placing a cylindrical base member in a reactor which can be evacuated, the reactor having an electrode therein, so as to be spaced apart from the electrode;
(ii) introducing a raw material gas for deposited film formation into the reactor; and
(iii) applying an alternating voltage of a rectangular wave having a frequency of 3 kHz or more and 300 kHz or less between the electrode and the cylindrical base member so that a potential at the cylindrical base member with respect to a potential at the electrode becomes alternately positive and negative during one period of the rectangular wave, to decompose the raw material gas, and forming a deposited film on the cylindrical base member,
wherein, when,
the potential difference between the electrode and the cylindrical base member whose potential with respect to the electrode is the positive, is defined as a first potential difference, and
the potential difference between the electrode and the cylindrical base member whose potential with respect to the electrode is the negative, is defined as a second potential difference,
one of the first potential difference and the second potential difference is a value (V 1 ) less than the absolute value of a discharge maintaining voltage, and the other is a value (V 2 ) greater than or equal to the absolute value of a discharge starting voltage, the discharge maintaining voltage being lower than the discharge starting voltage, and
wherein, when the one period of the rectangular wave is defined as T, a period during which the absolute value of the potential difference between the electrode and the cylindrical base member is the value (V 2 ) is defined as t 2 , and a value obtained by dividing t 2 by T (t 2 /T) is defined as duty ratio, the duty ratio is 20% or more and 80% or less.
2. The method for manufacturing an electrophotographic photosensitive member according to claim 1 , wherein the V 1 is a value that is 20% or more of the V 2 .
3. The method for manufacturing an electrophotographic photosensitive member according to claim 1 , wherein the V 1 is a value that is 95% or less of the absolute value of the discharge maintaining voltage.
4. The method for manufacturing an electrophotographic photosensitive member according to claim 1 , wherein in the step (iii), the potential at the electrode is constant.
5. The method for manufacturing an electrophotographic photosensitive member according to claim 4 , wherein in the step (iii), the potential at the electrode is a ground potential.
6. The method for manufacturing an electrophotographic photosensitive member according to claim 1 , wherein the rectangular wave is a rectangular wave having a frequency of 10 kHz or more and 100 kHz or less.
7. The method for manufacturing an electrophotographic photosensitive member according to claim 1 , wherein at least one species of the raw material gas is a hydrogenated silicon gas, and the deposited film is an amorphous film.
8. The method for manufacturing an electrophotographic photosensitive member according to claim 1 , wherein the electrode forms at least part of an inner wall of the reactor.