Plasma CVD device and method of manufacturing magnetic recording medium

1. A plasma CVD device comprising:

a chamber;

an anode which is arranged within said chamber and which has an electrode surface on a front surface;

a cathode which is arranged within said chamber;

a holding portion which is arranged within said chamber and which holds a substrate to be deposited which is arranged so as to face said electrode surface of said anode and said cathode;

a plasma wall which is arranged within said chamber and which is provided so as to cover a space between said substrate to be deposited held by said holding portion and each of said electrode surface of said anode and said cathode;

an anti-adhesion member which is arranged between a first gap between said anode and said plasma wall and a first inner surface of said chamber and which is in contact with said first inner surface of said chamber;

a pedestal which is arranged between said anti-adhesion member and a back surface of said anode and between the back surface of said anode and a second inner surface of said chamber and which is electrically connected to said anode;

a spacer which is arranged between said back surface of said anode and a third inner surface of said chamber and which is in contact with said third inner surface;

a first direct-current power source which is electrically connected to said pedestal;

an alternating-current power source which is electrically connected to said cathode;

a second direct-current power source which is electrically connected to said substrate to be deposited held by said holding portion;

a gas supply mechanism which supplies a raw material gas into said chamber; and

an exhaust mechanism which exhausts said chamber,

wherein each of a maximum diameter of said first gap, a maximum diameter of a second gap between said anode and said anti-adhesion member, a maximum diameter of a third gap between said back surface of said anode and said spacer, a maximum diameter of a fourth gap between said plasma wall and said anti-adhesion member, a maximum diameter of a fifth gap between said anti-adhesion member and said pedestal and a maximum diameter of a sixth gap between said pedestal and said spacer is equal to or less than 4 mm;

said first inner surface of said chamber faces said plasma wall and said pedestal;

said second inner surface of said chamber faces said pedestal; and

said third inner surface of said chamber faces said back surface of said anode.

2. The plasma CVD device according to claim 1 , wherein an insulator is formed on each of a surface facing each of said first gap and said second gap of said anode, a surface facing each of said third gap and said sixth gap of said spacer, a surface facing each of said second gap, said fourth gap and said fifth gap of said anti-adhesion member, a surface facing each of said fifth gap, said sixth gap and said second inner surface of said pedestal and a surface facing each of said first gap and said fourth gap of said plasma wall.

3. The plasma CVD device according to claim 2 , wherein an insulator is formed on each of a surface facing said first inner surface of said anti-adhesion member and a surface facing said third inner surface of said spacer.

4. The plasma CVD device according to claim 2 , wherein an insulator is formed on a surface facing said third gap of said back surface of said anode.

5. The plasma CVD device according to claim 2 , wherein an insulator is formed on a surface other than said electrode surface of said anode.

6. The plasma CVD device according to claim 2 , wherein said insulator is a substance which has a volume resistivity of 1 ×10 10 Ωcm or more at 20 ° C. and which has heat resistance to 100 ° C.

7. The plasma CVD device according to claim 2 , wherein said insulator is individually any of glass, quartz, resin, ceramics, a thermally sprayed insulator, an insulator subjected to alumite treatment and ceramic plating.

8. The plasma CVD device according to claim 2 , wherein a thermally sprayed conductive film is formed either on a surface on which said insulator of said anode is not formed or on said electrode surface of said anode.

9. The plasma CVD device according to claim 1 ,

wherein each of said spacer, said anti-adhesion member and said plasma wall is formed of an insulator, and

an insulator is formed on each of a surface facing each of said first gap and said second gap of said anode and a surface facing each of said fifth gap, said sixth gap and said second inner surface of said pedestal.

10. The plasma CVD device according to claim 1 , wherein a thermally sprayed conductive film is formed on a surface of said anode.

11. A method of manufacturing a magnetic recording medium using the plasma CVD device according to claim 1 ,

wherein a substrate to be deposited in which at least a magnetic layer is formed on a non-magnetic substrate is held by said holding portion, and

said raw material gas is brought into a plasma state by a discharge between said cathode and said electrode surface of said anode within said chamber, and the plasma is accelerated to collide with a surface of said substrate to be deposited held by said holding portion to thereby form a protective layer whose main component is carbon.

12. A method of manufacturing a magnetic recording medium including forming a protective layer whose main component is carbon, after at least a magnetic layer is formed on a non-magnetic substrate,

wherein said protective layer is formed using the plasma CVD device according to claim 1 .