| 摘要 |
PURPOSE:To make correction due to difference in the characteristics of detectors unnecessary and to accurately perform the monitoring of development by detecting 0th-order diffracted light and 1st-order diffracted light obtained according to the progress of the development by one detector. CONSTITUTION:An optical master disk 1 is held on a chuck table 2, and spin development is applied on it by a spindle 3. A group is formed on the pattern plane of the master disk 1 according to the progress of the development, and the 0th-order diffracted light (b) and the 1st-order diffracted light (c) can be obtained by projecting a laser beam (a). The diffracted light (b) and (c) are made incident on the same detector 7 under the control of a detection control part 4 via shutters 5 and 6 which open and close alternately, and a diffracted light ratio (k) is operated at a diffracted light ratio monitoring part 9. By monitoring the diffracted light ratio (k), it is possible to monitor the progressive state of the development accurately without being affected by the sensitivity characteristic of the detector 7 or the change of the characteristic according to the offset of an amplifier 8, the difference and deterioration in gain characteristics. |
