In a method of measuring, in a lithographic manufacturing process using a
lithographic projection apparatus, overlay between a resist layer, in
which a mask pattern is to be imaged, and a substrate, use is made of an
alignment-measuring device forming part of the apparatus and of specific
overlay marks in the substrate and resist layer. These marks have
periodic structures with periods which cannot be resolved by the
alignment device, but generate an interference pattern having a period
corresponding to the period of a reference mark of the alignment device.