| 摘要 |
PURPOSE:To enable high measurement accuracy by installing a semiconductor sensor behind an exposure shutter, and opening or closing this shutter during measurement and synchronizing it with the opening and closing of this shutter so as to obtain the output of a semiconductor sensor to calculate the illuminance of the exposing light. CONSTITUTION:When measuring the illuminance of X-rays, first a stage 107 is shifted to the outside of the opening of an aperture 107 so that a wafer 108 on the stage 107 may not be irradiated with X-rays. Next, when a shutter 101 is moved right and left at high speed, pulse currents are obtained from a sensor 103, and AC component can be obtained by synchronizing it with the driving period of the shutter 101 at a signal processing part 112, and the fluctuating component of the dark current is canceled and accurate X-rays intensity can be measured. Hereby, exposure illuminance can be measured in high accuracy. |
