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:
Jul. 23, 1991
Filed:
Apr. 27, 1990
Philip A Trask, Laguna Hills, CA (US);
Gabriel G Bakhit, Huntington Beach, CA (US);
Vincent A Pillai, Irvine, CA (US);
Kirk R Osborne, Los Angeles, CA (US);
Kathryn J Berg, Long Beach, CA (US);
Gary B Warren, Huntington Beach, CA (US);
Hughes Aircraft Company, Los Angeles, CA (US);
Abstract
A via (26) is formed through a dielectric layer (8) separating two conductive layers (16,28) by establishing a laterally erodible mask (18) over the dielectric (8), with a window (24) over the desired via location. The mask (18) and exposed dielectric material (8) are eroded simultaneously, preferably by reactive ion etching, producing a via (26) through the dielectric (8) which expands laterally as vertical erosion proceeds. The erosion conditions, the materials for the mask (18) and dielectric (8), and the initial window (24) taper are selected so that the final via (26) is tapered at an angle of less than about 45.degree. to the lower metal layer (6), and preferably about 30.degree.-45.degree., to enable a generally uniform width for the upper metallization (28) in the via (26). A non-erodible mask (10) is established over the dielectric layer (8) lateral to the via (26) during fabrication to prevent the propagation of pinhole defects from the erodible mask (18) into the dielectric (8), and is normally removed prior to completing the structure.