| 摘要 |
PROBLEM TO BE SOLVED: To make the states of pinching members which pinch a substrate surely detectable through a simple adjusting work. SOLUTION: A spin chuck 1 has a rotary shaft 25 and a plurality of pinching members F2 which pinch a wafer W, and, at the same time, can cancel the pinching state. A substrate holding device is provided with interlocked rings 34 and 44 which rotate together with the spin chuck 1 so as to surround the rotary shaft 25 and, in addition, move upward and downward in an interlocked state with the operations of the pinching members F2. The heights of the rings 34 and 44 are detected by means of a position sensor. The sensor outputs detect signals which continuously vary in accordance with the heights of the rings 34 and 44. The output of the position sensor is digitized and the state (opened state, pinching state, substrate slipping state, and no-wafer state) of the pinching members F2 is discriminated based on the digitized positional information. COPYRIGHT: (C)2005,JPO&NCIPI |
