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. 16, 2004
Filed:
Sep. 07, 2001
John P. McCormick, Palo Alto, CA (US);
LSI Logic Corporation, Milpitas, CA (US);
Abstract
A method for providing under bump metallization on a substrate. Trenches are formed in the substrate, and a layer of first electrically conductive material is formed over the substrate. The layer of the first electrically conductive material substantially fills the trenches and substantially covers the substrate between the trenches in a contiguous sheet. The layer of the first electrically conductive material is thinned to an end point where the layer of the first electrically conductive material is substantially reduced in thickness, but still forms the contiguous sheet between the trenches. A layer of photoresist is applied over the layer of the first electrically conductive material to define openings. A second electrically conductive material is deposited into the openings. The photoresist layer is removed, and the layer of the first electrically conductive material in the contiguous sheet between the trenches is removed to isolate the first electrically conductive material in the trenches. Because the layer of the first electrically conductive material is not completely removed in the areas between the trenches, the first electrically conductive material may be used as an electrode for the electroplate deposition of the second electrically conductive material. Thus, the under bump metallization can be produced in a more economical manner. If the layer of the first electrically conductive material were to be thinned to the point where the first electrically conductive material was only left in the trenches, then it would not be feasible to used the layer of the first electrically conductive material as an electrode, and thus it would further not be feasible to electroplate the second electrically conductive material.