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. 12, 1991
Filed:
Oct. 29, 1990
Stephen S Poon, Austin, TX (US);
Avgerinos V Gelatos, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
In a polish palnarization process using a polishing apparatus and an abrasive slurry, a boron nitride (BN) polish stop layer (18) is provided to increase the polish selectivity. The BN layer deposited in accordance with the invention has a hexagonal-close-pack crystal orientation and is characterized by chemical inertness and high hardness. The BN layer has a negligible polish removal rate yielding extremely high polish selectivity when used as a polish stop for polishing a number of materials commonly used in the fabrication of semiconductor devices. In accordance with the invention, a substrate (12) is provided having an uneven topography including elevated regions and recessed regions. A BN polish stop layer (18) is desposited to overlie the substrate (12) and a fill material (20, 36) which can be dielectric material or a conductive material, is deposited to overlie the BN polish stop (18) and the recessed regions of the substrate. The fill material is then polished back until the BN polish stop is reached resulting in the formation of a planar surface (38).