Self-aligned structure, especially for semiconductor, micro-optical or micromechanical devices, is produced using an existing substrate structure as mask for back face resist layer exposure

摘要

Photolithographic self-aligned structure production on a structured substrate surface, by using the already existing structure as mask for back face resist layer exposure, is new. Self-aligned photolithographic production of a second structure on a substrate surface having a first structure comprises (a) forming the first structure as a first thin film and an overlying second thin film which is laterally under-etched by a preset distance; (b) removing the second thin film; (c) applying an opaque etch-stop layer which does not cover the etch edges of the first thin film; (d) laterally under-etching the etch-stop layer for complete removal of the first thin film; (e) applying and back face exposing a resist layer using the etch-stop layer as an optical mask; (f) developing the resist layer to expose the substrate surface for producing the second structures; and (g) removing the resist layer and the etch-stop layer.