The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 29, 1983
Filed:
Mar. 26, 1982
Peter L Young, North Wales, PA (US);
Barry F Stein, Dresher, PA (US);
John E Sheppard, Cornwells Heights, PA (US);
Sperry Corporation, New York, NY (US);
Abstract
The present invention teaches a method of planarizing built-up vacuum deposited surfaces or areas on Josephson junction and semiconductor devices so that successively deposited layers do not replicate the undulations of previous layers. After a surface layer is deposited in a vacuum system and part of the surface is etched, a raised surface is generated. A photoresist lift-off stencil is applied to the surface to be preserved and the material to be removed is removed by isotropically etching so as to leave an overhang or ledge of photoresist material over the area of the material retained. A new layer of material is now deposited by vacuum deposition so as to almost fill the area to be planarized. A small gap remains between the top of the new material being vacuum deposited and the botton of the photoresist stencil so that solvent can be introduced to the stencil. When the photoresist stencil is removed, the top of surface being preserved is substantially planar with the new layer of material.