Patent ID: 7935217

Claim:
A substrate processing apparatus which treats a substrate with predetermined processing by holding said substrate in a predetermined position and supplying a processing liquid to said substrate while rotating said substrate, comprising: a bevel unit which includes a first nozzle and a second nozzle, which supply said processing liquid to a rim portion of said substrate, said bevel unit being structured to rotate freely about a rotation axis which extends in a direction of a rotation axis of said substrate; a drive mechanism which moves said nozzle to an opposed position and to a far position by driving said bevel unit, the opposed position being a position which is opposed against the rim portion of said substrate, and the far position being a position which is away from said substrate; a first optical distance sensor and a second optical distance sensor disposed to perform non-contact detection of a distance between said nozzle and a circumferential edge surface of said substrate; and a controller which is configured to rotate said bevel unit about the rotation axis to adjust the distance between said first and second nozzles and the circumferential edge surface of said substrate by controlling said drive mechanism based on detection signals from said first and second optical distance sensors, wherein said bevel unit includes a back-surface-side main unit member which is opposed against a back surface of said substrate and a front-surface-side main unit member which is opposed against a front surface of said substrate and is provided with said nozzles; said second nozzle being disposed on an upstream side in a rotation direction of said substrate relative to said first nozzle, said first optical distance sensor being disposed in said bevel unit on a downstream side in the rotation direction of said substrate relative to said first nozzle, and said second optical distance sensor being disposed in said bevel unit on an upstream side in the rotation direction of said substrate relative to said second nozzle.