To effectively utilize the photoelectric conversion surface of an electron beam exposure device by suppressing the out-of-focus of a pattern formed on a wafer and preventing the deterioration of the photoelectric conversion surface.

An electron beam exposure device 1 is provided with an ultraviolet-ray illuminating section 2 which projects a pattern by projecting ultraviolet rays 6 upon a reticle mask 14 on which the pattern is formed, a photoelectric conversion section 18 having a photoelectric conversion surface 21 which converts the ultraviolet rays 6 transmitted through the mask 14 into an electron beam 24, and an electron beam exposure section 3 which projects and aligns the pattern upon and on a wafer 30 by projecting the electron beam 24 upon the wafer 30. On the lower surface of the photoelectric conversion surface 21, a conductive member plate 22 having a circular arcuate opening 22a which is formed to transmit the electron beam 24 emitted from the photoelectric conversion surface 21 is provided.