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:
Dec. 20, 1994
Filed:
Sep. 27, 1993
Nicholas G Koopman, Raleigh, NC (US);
Glenn A Rinne, Cary, NC (US);
Iwona Turlik, Raleigh, NC (US);
Edward K Yung, Carrboro, NC (US);
MCNC, Research Triangle Park, NC (US);
Abstract
An integrated circuit chip having solder bumps thereon may be tested using a temporary substrate having substrate pads corresponding to locations of the input/output pads on the chip and having a sacrificial conductor layer on the temporary substrate pads. The solder bumps are placed adjacent the corresponding sacrificial metal layer and heated to form an electrical and mechanical connection between the chip and the temporary substrate. The chip is then tested and/or burned-in on the temporary substrate. After testing/burn-in, the sacrificial metal layer is dissolved into the solder bumps by heating. The integrated circuit chip, including a solder bump having the dissolved sacrificial metal layer therein, may be easily removed from the temporary substrate. Solder bumps may also be formed on the temporary substrate and transferred to unbumped chips. Solder bumps with different characteristics may be formed by varying the current-time product to each individual pad of the temporary substrate during a plating operation.