Method for fabricating thin film metallic meshes for use as Fabry-Perot interferometer elements, filters and other devices

US4818661A · kind A · utility

Assignee

• United States of America as represented by the Secretary of the Air Force · US

Inventors

• Charles Taylor · Claremont, US
• Julius Grossman · Randallstown, US
• Jacqueline Fischer · Silver Spring, US
• Howard A. Smith · Bethesda, US
• Martin C. Peckerar · Silver Spring, US
• Milton L. Rebbert · Elkridge, US

Key dates

• Filing date: Jul 21, 1987
• Grant date: Apr 4, 1989
• Expiry date: Jul 21, 2007

Classification

• Technology area (CPC G): Physics
• CPC primary: G03F7/12
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A method of fabricating a free-standing wire mesh grid pattern having a sth, flat surface is disclosed. A thermal oxide is selectively applied to front and back sides of a silicon substrate. A central portion of the oxide on the back side is removed. A resist layer is applied onto the oxide on the front side of the substrate. A resist mesh pattern with a border encompassing that resist mesh pattern is lithographically developed on the resist layer. Chrome and gold layers are sequentially deposited onto the border and into the resist mesh pattern to create a wire mesh pattern within the resist mesh pattern. The resist layer, including the developed resist mesh pattern, is removed to expose the wire mesh pattern from the front side of the substrate. A nickel layer is deposited over the gold layer to develop a wider wire mesh pattern. A second gold layer is then deposited over the nickel layer to form a wire mesh grid pattern composed of chrome, gold, nickel and gold layers. Central portions of the substrate and the oxide on the front side of the substrate are removed to expose the wire mesh grid pattern from the back side of the substrate. Finally, the chrome layer is removed to prod…