Patent ID: 8038838

Claim:
A spin head for holding and rotating a substrate during a process, the spin head comprising: a rotatable body; chucking/unchucking means disposed to be ring-shaped around the center of a top surface of the body and including a plurality of chucking pins provided to partially chuck and unchuck the edge of the substrate during a process; and a driving unit for rotating the chucking pins at a predetermined angle to selectively vary portions where the respective chucking pins are in contact with the substrate, wherein the driving unit comprises: a lifting member movable up and down, the lifting member including an elevating ring having a substantially ring shape and forming an upper end of an elevating rod configured to elevate the elevating ring or lower the elevating ring, the elevating ring and elevating rod thereby forming a single integral body, the elevating ring of the integral body further including a magnet formed into a top surface portion of the elevating ring; and a movement conversion member configured to convert up-down movement of the lifting member to rotation movement of the chucking pins, the movement conversion member including a rack-gear member having a gear body with a magnet affixed directly to its body lower end so as to be in facing relation with the magnet formed in the top surface portion of the elevating ring, the elevating ring directly below the gear body and movable up and down in a vertical plane to generate a repulsive force between the facing magnets, the repulsive force making the rack-gear member move up and down.