Inspection method of photomask reticle for semiconductor device

Abstract

A method of inspecting a photomask reticle for the fabrication of a semiconductor device such as a die having a first pattern which has its own individual shape and a plurality of second patterns each having the same shape and size among themselves, combining the methods of the database inspection and of the pattern comparing inspection. The method of database inspection is applied to the first pattern and to one of the second patterns selected randomly. The database inspection can be performed by comparison with inspection data derived from design data used for the fabrication of the photomask reticle, such as by an improved reticle tester which can exclude all of the second patterns except the selected one of the second patterns. The second patterns other than the selected pattern are then inspected by the method of the pattern comparing inspection, that is, by comparison with the selected second pattern which has already been inspected by the database inspection. The volume of the storage for the inspection data and the time required to inspect the photomask reticle can be reduced to less than one fourth of those in the prior art inspection method, while maintaining high accuracy in the inspection of photomask reticles.