Abstract: A multi-gap mask is provided which enables worked patterns each having a different height to be concurrently and collectively formed. In the multi-gap mask, first and second mask patterns are formed which are fixed on/over a surface of an object to be worked when sandblasting is performed on the surface of the object to be worked and each of which has a different gap from the surface of the object to be worked. The first mask pattern is made up of a plurality of metal wires and a second mask pattern is made up of a plurality of a rectangular-parallelepiped-shaped photosensitive emulsion. By using the multi-gap mask having a gap from the surface of the object to be worked and a velocity distribution of a viscous fluid in a gap region, a worked pattern having various depths can be concurrently and collectively fabricated without an increase in numbers of man-hours.