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. 18, 2003
Filed:
Nov. 15, 1999
Abram M. Castro, Fort Worth, TX (US);
Substrate Technologies Incorporated, Carrollton, TX (US);
Abstract
A package substrate suitable for use with a ball grid array according to the invention includes an electrically and thermally conductive heat sink having a top surface and a bottom surface, the heat sink having a slot formed therethrough which opens onto the top and bottom surfaces. A dielectric layer is formed on the bottom surface of the heat sink proximate the slot, preferably directly thereon without an intervening adhesive layer. A circuit is selectively formed in a circuit pattern on the dielectric layer. An electrically resistive soldermask is disposed on the dielectric layer and the circuit, which soldermask has openings therethrough which expose bond pads of the circuit. Such a substrate according to the invention permits the integrated circuit die to be mounted over the slot in the manner of a lead-on-chip package, but provides bond pads to which solder balls can be mounted in order to form a ball grid array.