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:
Mar. 22, 1988
Filed:
Nov. 15, 1985
Roland A Levy, Berkeley Heights, NJ (US);
Kurt Nassau, Bernardsville, NJ (US);
American Telephone and Telegraph Company, AT&T Bell Laboratories, Murray Hill, NJ (US);
Abstract
A glass reflow step to round off sharp edges of contact vias is typically included in processes for making integrated-circuit devices. In the course of making such devices with closely spaced vias, it has been found that unacceptable overhangs occur on the sidewalls of the vias. Neither changes in the composition of the glass nor modifications in the processing parameters of reflow were effective to avoid the overhang phenomenon. In accordance with the invention, it has been discovered that the overhang problem can be consistently avoided if the ratio of glass thickness to via-to-via spacing is about .ltoreq.0.393.