Provided is a method of plasma etching on a substrate using an etchant gas mixture to meet integration objectives, the method comprising: disposing a substrate having a structure pattern layer, a neutral layer, and an underlying layer, the structure pattern layer comprising a first material and a second material and the underlying layer comprising a silicon anti-reflective (SiARC) layer, a spin-on carbon hardmask (CHM) layer, an oxide layer, and a target layer; performing an first etch process to selectively remove the second material and the neutral layer using a first etchant gas mixture to form a first pattern; performing an second etch process to selectively remove the SiARC layer to form a second pattern; performing an third etch process to selectively remove the CHM layer to form a third pattern; concurrently controlling selected two or more operating variables wherein the first etchant gas include oxygen and sulfur-containing gases.