A method for fabricating a layer structure having a target topology profile in a step which has a side face and a lateral face, includes processes of: (a) depositing a dielectric layer on a preselected area of the substrate under first deposition conditions, wherein the dielectric layer has a portion whose resistance to fluorine and/or chlorine radicals under first dry-etching conditions is tuned; and (b) exposing the dielectric layer obtained in process (a) to the fluorine and/or chlorine radicals under the first dry-etching conditions, thereby removing at least a part of the portion of the dielectric layer, thereby forming a layer structure having the target topology profile on the substrate.