Method for defining a separating structure within a semiconductor device

A method includes depositing a material layer over a semiconductor substrate and using a first mask in a first exposure/patterning process to pattern the material layer thereby forming a plurality of first and second features. The first features include patterns for the semiconductor device and the second features include printing assist features. The method includes using a second mask in a second exposure/patterning process to effectively remove the second features from the material layer and to define at least one separating structure between two first features.