| 摘要 |
PURPOSE:To obtain the exposure device which is difficult to receive the influence of defects, dust, dirt, etc. by using computer holograms and optical systems such as lasers, beam expanders and making use of the redundancy of holography. CONSTITUTION:The light out from a laser 27 is expanded of its luminous flux by a beam expander 28 and radiates a computer hologram 29. The real image 31 of patterns is reconstructed on a wafer 30 and the patterns are formed on the wafer 30. Since the hologram 29 has redundancy, the influence of the defects, dust, dirt, etc. on the hologram does not appear on the reconstructed image 31. With the computer hologram, the information of the patterns is input by coondinates into a computer 32, then high-speed Fourier transformation takes place and the interference patterns on the hologram are calculated and these are drawn by a plotter 33 and the original picture 34 thus made is subjected to photographic reduction, whereby it is completed. |
