MULTI-LAYER STRUCTURE AND METHOD OF FABRICATION THEREOF

摘要

A multi-layer structure that includes a transparent dielectric substrate, a layer of a nickel-containing steel alloy, and a layer of copper and/or chromium. The structure is used as multi-density photomasks for example. The process for fabricating multi-layer structure, like a multi-density photomask comprises: a) providing a transparent dielectric substrate having a steel layer and a layer of a metal, like of copper, thereon with the layer of said steel is deposited on top of said layer of a metal or vice versa; b) providing a layer of photoresist material on top of the structure provided in step (a); c) exposing and developing said layer of photoresist material; d) selectively etching exposed portion of said metal or said steel; e) selectively etching exposed portion of said metal or said steel not etched in step (d); f) exposing and developing photoresist on the said layer of said metal or said steel etched in step (d); g) selectively etching exposed portion of said metal or said steel of step (f); and h) removing the photoresist. t