Method of etching insulating film and method of forming interconnection layer

Abstract

A method of rapid etching of an insulating film including an organic-based dielectric film without forming a damage layer or causing decline of the throughput, including the steps of forming an insulating film including an organic-based dielectric film such as a stacked film comprised of a polyarylether film or other organic-based dielectric film and a silicon oxide-based dielectric film or other insulating film, forming a mask layer by patterning above the insulating film, and when etching the organic-based dielectric film portion, using ions or radicals containing NH group generated by gaseous discharge in a mixed gas of hydrogen gas and nitrogen gas or a mixed gas of ammonia gas for etching using the mask layer as an etching mask, to etch the insulating layer and form openings etc. while generating reaction products containing CN group.