| 摘要 |
PURPOSE:To obtain the small-sized equipment by forming a structure in which several interference filters and several photo detectors are arranged two- dimensionally and the arrays of them are confronted to each other three- dimensionally. CONSTITUTION:When the shutter is opened in an aligner, the wafer is exposed and, at the same time, the penetrating light through the mirror 8 illuminates the photo detector, which generates the output voltage Vout being impressed on the integration circuit 41. The output voltage of the integration circuit 41 is delivered to the one input terminal 43 of the comparator 42, and the exposure set circuit 45 is connected to the other input terminal. Then the comparator 42 inverts its state when the output voltage of the integration circuit 41 exceeds the reference voltage Vref given by the exposure set circuit 45. Consequently, the adequate exposure can be obtained by adjusting the reference voltage Vref with a variable resister and applying the output voltage Vcmp of the comparator 42 to the shutter-closing signal. |
