An exposure method according to the present invention includes a first step of forming on a substrate an alignment mark including a concave and convex pattern; a second step of forming a coat over said alignment mark and the other area on said substrate; a third step of flattening said coat; and a fourth step of applying a photosensitive material on said coat flattened by said third step and projecting a mask pattern thereto. The alignment mark is formed by said concave and convex pattern arranged with a pitch which is smaller than the predetermined value between adjacent convex portions having a width of not less than a predetermined value.