Substrate processing apparatus

1. A substrate processing apparatus for processing a substrate, comprising:

a substrate holding part for holding a substrate;

a substrate rotation mechanism for rotating said substrate holding part about a central axis perpendicular to said substrate; and

a magnetic-material movement mechanism for mounting a first chucking magnetic material on said substrate holding part and removing said first chucking magnetic material from said substrate holding part,

wherein said substrate holding part includes:

a chuck support part; and

at least three chuck members supported on said chuck support part,

said at least three chuck members includes at least one movable chuck member whose position can be changed between a chuck position and an unchuck position, and

each movable chuck member included in said at least one movable chuck member includes a second chucking magnetic material that applies a force that holds an outer edge portion of said substrate on said each movable chuck member by magnetic action between said first chucking magnetic material and said second chucking magnetic material when said first chucking magnetic material is mounted on said substrate holding part.

2. The substrate processing apparatus according to claim 1 , further comprising:

a shield plate that faces an upper surface of said substrate,

wherein said shield plate includes said first chucking magnetic material, and

said magnetic-material movement mechanism is a shield-plate elevating mechanism for moving said shield plate up and down.

3. The substrate processing apparatus according to claim 1 , wherein

said substrate rotation mechanism includes:

a rotor that has an annular shape centered about said central axis and includes a permanent magnet; and

a stator that has an annular shape centered about said central axis and rotates said rotor that is in a floating state.

4. The substrate processing apparatus according to claim 1 , wherein

said substrate holding part includes an unchucking part for applying an unchucking force that holds said at least one movable chuck member at said unchuck position on said at least one movable chuck member when said first chucking magnetic material and said second chucking magnetic material are away from each other.

5. The substrate processing apparatus according to claim 4 , wherein

said unchucking part includes first and second unchucking magnetic materials, and

said unchucking force is magnetic action produced between said first and second unchucking magnetic materials.

6. The substrate processing apparatus according to claim 1 , wherein

each movable chuck member included in said at least one movable chuck member is turnable about a turning axis, and

a force that turns said each movable chuck member in a direction for holding said substrate is exerted on said each movable chuck member by a centrifugal force produced by rotation of said substrate holding part.

7. The substrate processing apparatus according to claim 1 , wherein

when the position of said at least one movable chuck member is changed from said chuck position to said unchuck position while said first chucking magnetic material is mounted on or in close proximity to said substrate holding part, said at least one movable chuck member comes in contact with said first chucking magnetic material before the hold on said substrate is released.

8. A substrate processing apparatus for processing a substrate, comprising:

a substrate holding part for holding a substrate;

a substrate rotation mechanism for rotating said substrate holding part about a central axis perpendicular to said substrate; and

an unchucking part for releasing the hold on said substrate by said substrate holding part,

wherein said substrate rotation mechanism includes:

a rotor that has an annular shape centered about said central axis and includes a permanent magnet; and

a stator that has an annular shape centered about said central axis and rotates said rotor that is in a floating state,

said substrate holding part includes:

a chuck support part; and

at least three chuck members that are supported on said chuck support part,

said at least three chuck members includes:

at least one fixed chuck member that is fixed to said chuck support part; and

at least one movable chuck member whose position can be changed between a chuck position and an unchuck position,

a force that holds an outer edge portion of said substrate acts on said at least one movable chuck member when said substrate is held by said substrate holding part, and

said unchucking part includes:

a contact part;

a contact-part movement mechanism for moving said contact part in a direction along said central axis such that said contact part contacts with and pushes said at least one movable chuck member to change the position of said at least one movable chuck member from said chuck position to said unchuck position; and

an anti-tilt part for preventing tilting of said chuck support part while said contact part is in contact with said at least one movable chuck member.

9. The substrate processing apparatus according to claim 8 , wherein

said unchucking part includes, as said anti-tilt part:

another contact part; and

a second contact-part movement mechanism for moving said another contact part in a direction along said central axis and pushing said another contact part into contact with said chuck support part or said at least one fixed chuck member to maintain a holding-part central axis in parallel with said central axis of said substrate rotation mechanism, said holding-part central axis being a central axis of said substrate holding part.

10. The substrate processing apparatus according to claim 9 , wherein

said another contact part pushes said at least one fixed chuck member or a portion of said chuck support part in the vicinity of said at least one fixed chuck member.

11. The substrate processing apparatus according to claim 8 , wherein

said unchucking part includes, as said anti-tilt part:

an anti-tilt member whose position relative to said stator is fixed or can be fixed and that prevents tilting of said chuck support part by coming in contact with said chuck support part or a portion whose position relative to said chuck support part is fixed, while said contact part is in contact with said at least one movable chuck member.

12. The substrate processing apparatus according to claim 11 , wherein

said unchucking part further includes a retracting mechanism for retracting said anti-tilt member from a rotating portion when said substrate is rotated along with said substrate holding part.

13. The substrate processing apparatus according to claim 11 , wherein

said unchucking part further includes another anti-tilt member that is disposed at a different position from said anti-tilt member in a circumferential direction, and

said anti-tilt member and said another anti-tilt member are in contact with said chuck support part or said portion whose position relative to said chuck support part is fixed.

14. The substrate processing apparatus according to 8 , further comprising:

a shield plate that faces an upper surface of said substrate; and

a shield-plate elevating mechanism for moving said shield plate up and down,

wherein said shield plate includes a first chucking magnetic material, and

each movable chuck member included in said at least one movable chuck member includes a second chucking magnetic material that applies said force that holds the outer edge portion of said substrate on said each movable chuck member by magnetic action between said first chucking magnetic material and said second chucking magnetic material when said shield plate is moved into close proximity to said upper surface of said substrate.

15. The substrate processing apparatus according to claim 8 , further comprising:

a magnetic-material movement mechanism for mounting a first chucking magnetic material on said substrate holding part and removing said first chucking magnetic material from said substrate holding part, or for moving a first chucking magnetic material into close proximity to said substrate holding part and moving said first chucking magnetic material away from said substrate holding part,

wherein each movable chuck member included in said at least one movable chuck member includes a second chucking magnetic material that applies said force that holds the outer edge portion of said substrate on said each movable chuck member by magnetic action between said first chucking magnetic material and said second chucking magnetic material when said first chucking magnetic material is mounted on said substrate holding part or moved into close proximity to said substrate holding part.

16. The substrate processing apparatus according to claim 8 , wherein

said substrate holding part further includes:

a first chucking magnetic material that is fixed to said chuck support part; and

a second chucking magnetic material that applies said force that holds the outer edge portion of said substrate on said at least one movable chuck member by magnetic action between said first chucking magnetic material and said second chucking magnetic material.

17. A substrate processing apparatus for processing a substrate, comprising:

a substrate holding part for holding a substrate;

a substrate rotation mechanism for rotating said substrate holding part about a central axis perpendicular to said substrate;

a magnetic-material movement mechanism for mounting a first chucking magnetic material on said substrate holding part and removing said first chucking magnetic material from said substrate holding part, or for moving a first chucking magnetic material into close proximity to said substrate holding part and moving said first chucking magnetic material away from said substrate holding part; and

a shield plate that faces an upper surface of said substrate,

wherein said substrate holding part includes:

a chuck support part; and

at least three chuck members supported on said chuck support part,

said at least three chuck members includes at least one movable chuck member whose position can be changed between a chuck position and an unchuck position,

each movable chuck member included in said at least one movable chuck member includes a second chucking magnetic material that applies a force that holds an outer edge portion of said substrate on said each movable chuck member by magnetic action between said first chucking magnetic material and said second chucking magnetic material when said first chucking magnetic material is mounted on said substrate holding part or moved into close proximity to said substrate holding part,

said shield plate includes said first chucking magnetic material, and

said magnetic-material movement mechanism is a shield-plate elevating mechanism for moving said shield plate up and down.

18. The substrate processing apparatus according to claim 17 , wherein

said substrate rotation mechanism includes:

a rotor that has an annular shape centered about said central axis and includes a permanent magnet; and

a stator that has an annular shape centered about said central axis and rotates said rotor that is in a floating state.

19. The substrate processing apparatus according to claim 17 , wherein

said substrate holding part includes an unchucking part for applying an unchucking force that holds said at least one movable chuck member at said unchuck position on said at least one movable chuck member when said first chucking magnetic material and said second chucking magnetic material are away from each other.

20. The substrate processing apparatus according to claim 17 , wherein

each movable chuck member included in said at least one movable chuck member is turnable about a turning axis, and

a force that turns said each movable chuck member in a direction for holding said substrate is exerted on said each movable chuck member by a centrifugal force produced by rotation of said substrate holding part.

21. The substrate processing apparatus according to claim 17 , wherein

when the position of said at least one movable chuck member is changed from said chuck position to said unchuck position while said first chucking magnetic material is mounted on or in close proximity to said substrate holding part, said at least one movable chuck member comes in contact with said first chucking magnetic material before the hold on said substrate is released.