As a step in performing a process on a structure, a hole pattern is provided in a thin layer of organic resin masking material formed over the structure to provide a process mask. A processing step is then performed through the openings in the mask, and after a processing step is completed the mask is adjusted by a re-flow process in which the structure is placed into an atmosphere of solvent vapor of a solvent of the mask material. By way of the reflow process, the mask material softens and re-flows to reduce the size of the openings in the mask causing edges of the surface areas on which the processing step was performed to be covered by the mask for subsequent processing steps.