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:
May. 12, 1987
Filed:
Jun. 29, 1984
Chakrapani G Jambotkar, Hopewell Junction, NY (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
In a semiconductor substrate having a trench isolation pattern formed therein, a method is taught for improving the planarity of the substrate and for improving the silicon nitride passivation at the trench peripheries. The quality of the trench edge is improved by providing for an undercut silicon dioxide layer and a recessed silicon sidewall arrangement below the silicon nitride layers resulting in better protection of the underlying SiO.sub.2 and Si regions. In further processing, improved planarity between the polyimide-filled trench and the adjacent substrate is achieved by establishing a polyimide etch-back point via a previously deposited oxide layer. Subsequent removal of the oxide does not affect the polyimide; the top of said polyimide being substantially planar with the adjacent substrate.