OPTICAL CHARACTERISTIC MEASURING METHOD AND DEVICE, SIGNAL SENSITIVITY SETTING METHOD, EXPOSURE UNIT AND DEVICE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To accurately measure the best focus position of a projection optical system regardless of the type of the measuring mark. SOLUTION: A specified measuring mark is irradiated with illumination light, and a space image of the measuring mark is formed on the image surface through the projection optical system. A pattern for measurement is relatively scanned with respect to the space image and a photoelectric transfer signal corresponding to the intensity of the illumination light through the pattern for measurement is obtained in every position in the direction of the optical axis of the pattern for measurement. Then the region which is surrounded by the photoelectric transfer signals obtained in the positions in the direction of the optical axis of the pattern for measurement, for example, the waveform of signals P1 and P2 and the scanning axis of the pattern for measurement is divided into a first region A (area A) indicating that it is near the best focus position of the projection optical system, and a second region B (area B) indicating that it is far from the best focus position. The best focus position is detected by regarding the area ratio between the first region and the second region A/B as an evaluation amount.