To realize the identification mask of a block mask which can be identified easily, without giving adverse effects to the aperture pattern of the block mask.

This aligner is provided with an electron gun, a block mask 21 with a plurality of kinds of aperture parts where an electron beam is selectively passed, a focussing means (projection lens) which focusses the electron beam passed through the selected patterns on a sample, a deflection means which deflects the electron beam passed through the selected aperture pattern on the sample, (an electromagnetic main deflector, and an electrostatic sub- deflector). The aligner is formed in such a manner that the pattern corresponding to the selected pattern are exposed all at a time. In this case, the block mask 21 is provided in a block mask region 51, and the identification means 71 is a fine pattern 72 provided on the base of the pitch approximating the wavelength of a light.