Method of reducing overlay error in via to grid patterning

A method of patterning a substrate, the method comprising:

• forming a first memorization layer on a target layer of a substrate;
• forming a second memorization layer on the first memorization layer;
• forming a multi-line layer above the second memorization layer, the multi-line layer including a region having a pattern of alternating lines of two or more differing materials, wherein each line has a horizontal thickness, a vertical height, and extends across the substrate, wherein each line of the pattern of alternating lines forms part of a top surface of the multi-line layer and vertically extends to a bottom surface of the multi-line layer, wherein at least two of the two or more differing materials differ chemically from each other by having different etch resistivities relative to each other;
• forming a first etch mask on the multi-line layer and executing a first etch process that etches into the first memorization layer using the first etch mask and one or more materials of the multi-line layer as a first combined etch mask;
• subsequent to executing the first etch process, removing a specific material from the multi-line layer and transferring a pattern defined by the multi-line layer into the first memorization layer;
• and
• subsequent to transferring the pattern defined by the multi-line later into the first memorization layer, forming a second etch mask on the multi-line layer and executing a second etch process that etches into the first memorization layer using the second etch mask and one or more materials of the multi-line layer as a second combined etch mask.