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:
Sep. 17, 1991
Filed:
Jul. 25, 1990
Philip J Spletter, Cedar Park, TX (US);
Colin A Mackay, Austin, TX (US);
Claire T Galanakis, Austin, TX (US);
John C Parker, Round Rock, TX (US);
Microelectronics and Computer Technology Corporation, Austin, TX (US);
Digital Equipment Corporation, Maynard, MA (US);
Abstract
A method is disclosed for laser bonding two highly reflective electrical members. The first electrical member is coated with a coating alloy containing the metal of the second electrical member and a coupling material that is well absorbent of laser energy at the laser beam wavelength, has a lower melting point than either of the electrical members, and has a low solubility in a solid bond alloy of the electrical members. The laser characteristics are selected so that as bonding occurs a bond alloy of the electrical members solidifies and a solidification front drives the molten coupling material away from the bond interface toward the exterior periphery of the bond, so that substantially all of the solidified bond interface and bond interface strength results from the bond alloy. Coating a copper lead with a coating alloy containing gold and a coupling material, and then contacting the coated copper lead with a gold bonding pad provides for gold-to-gold TAB tape laser bonding.