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:
Aug. 05, 1997
Filed:
Aug. 03, 1995
John Edward Cronin, Franklin County, VT (US);
Michael David Potter, Grand Isle County, VT (US);
Gorden Seth Starkey, Chittenden County, VT (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A method of etching vias without directional etching damage to the substrate. A pattern image is formed on an insulating layer of known thickness over a substrate. A conformal layer is formed on the pattern image. A vertical contact hole through the conformal layer and into the insulating layer is produced by directional etching. The directional etch also leaves conformal sidewall spacers of a defined width. The depth of the vertical contact hole is equal to the thickness of the insulating layer minus the width of the conformal spacer. The insulating layer is then removed by an isotropic wet etch to achieve a near vertical edge contact hole without directional etching damage to the substrate. The sidewall spacers may also be removed by etching prior to removal of the insulating layer.