an apparatus and method of etching . the apparatus including a support substrate having a top surface ; a stack of a multiplicity of layers formed on the top surface of the support substrate from a lowermost layer on the top surface of the support substrate to a topmost layer that is furthest from the support substrate ; and wherein an entirety of the top surface of the topmost layer is not planar and at least one of the multiplicity of layers that is not the topmost layer is an electrically conductive layer .