| 摘要 |
PURPOSE:To detect the shrunk part of a mask pattern by a method wherein a stage, having a plurality of vernier patterns graduated at different pitches, is shifted at a fixed speed and the shifting speed is detected by the pattern which looks as if it is at a standstill among the plurality of patterns. CONSTITUTION:The stage 2 of a guide section is shifted by a driving section 1. The mask 3, whereon the vernier patterns are graduated, is fixed on the stage 2. The vision of a lens systme 7 is projected on an image monitor 4, one of the vernier patterns on the image monitor is seen as if it is at a standstill while the driving section 1 and the vernier patterns are shifted at a fixed step and measurements. The patterns 11, 10 and 12 are looked as if they are at a standstill when the feed of the driving secion 1 is 50mum/pulse, 49mum/pulse and 51mum/pulse. Through these procedures, the shifting speed can be visually detected. The expansion and contraction of a substance can be detected when the shifting speed of the substance is unchanged . |
