Spin treatment apparatus

A spin treatment apparatus that performs a treatment while rotating a substrate, the apparatus comprising:

• at least three clamp pins configured to come into contact with an outer peripheral surface of the substrate and clamp the substrate;
• a plurality of rotatable pin rotators provided for the respective clamp pins and each configured to retain the corresponding clamp pin at a position offset from a rotation axis of the pin rotator which is parallel with a rotation axis of the substrate;
• a plurality of magnet gears provided for the respective pin rotators around outer peripheral surfaces thereof and each having a magnetic-pole part formed spirally about the rotation axis of the pin rotator;
• a plurality of rotation magnets provided for the respective magnet gears and positioned so as to attract and be attracted by the magnetic-pole part of the corresponding magnet gear;
• and
• a movement mechanism configured to move the plurality of rotation magnets in the direction of the rotation axes of the pin rotators.