Method to assay sacrificial light absorbing materials and spin on glass materials for chemical origin of defectivity

A method, comprising:

• analyzing a sacrificial light absorbing material with high performance liquid chromatography;
• forming a conductive layer on a substrate;
• forming a dielectric layer on the conductive layer;
• patterning a layer of photoresist, after forming the dielectric layer, to define a region to be etched;
• forming a first etched region by removing a first portion of the dielectric layer;
• filling the first etched region with the sacrificial light absorbing material;
• and
• forming a second etched region by removing the sacrificial light absorbing material and a second portion of the dielectric layer.