and or areas are to be removed when the patterns 22 h which have the square of the smallest allowable width a as the area thereof and which are allowed to remain intact by the conventional method fail to satisfy the standard of the smallest allowable area s their areas are to be enlarged since this enlargement results in widening the range of the focal point of the beam of light for exposure in which the transferred patterns remain without fail the dummy patterns can be transferred infallibly on a given substrate even when a difference of level in the surface of the substrate defocuses the beam of light for exposure further the formation of dummy layers which have been thinned by the thinning of the transferred patterns can be precluded because the isolated dummy patterns 22 g which satisfy the standard of width and do not satisfy the standard of area are removed such electrical defects as short circuits which are causable by separated conductive substances therefore can be prevented the embodiment given above has portrayed a case of restoring the removed dummy patterns 22 i and using them as connecting dummy patterns optionally new patterns may be formed instead the method under discussion has been described as using latticelike patterns as the reticular patterns 23 otherwise a pattern removing.