US Patent 7767386 Method of patterning an organic planarization layer

A method of patterning a thin film is described. The method comprises forming a thin film to be patterned on a substrate, forming a developable organic planarization layer (OPL) on the thin film, forming a developable anti-reflective coating (ARC) layer on the developable OPL, and forming a mask layer on the developable ARC layer. Thereafter, the mask layer, the developable ARC layer and the developable OPL are patterned to form a pattern therein using an imaging and developing process. The imaging and developing process may either partially extend or fully extend into the OPL. Once the mask layer is removed, the pattern is transferred to the underlying thin film using an etching process.