Populated printed wiring board and method of manufacture

Details Populated printed wiring board and method of manufacture Populated printed wiring board and method of manufacture

2007-01-23

2007-01-23

Cuneo, Kammie (Department: 2841)

Electricity: electrical systems and devices

Housing or mounting assemblies with diverse electrical...

For electronic systems and devices

C174S257000, C029S729000, C361S767000, C361S768000

Reexamination Certificate

active

10758822

ABSTRACT:
A populated printed wiring board (PWB) (100) and method of manufacturing the populated PWB are taught. The populated PWB is manufactured by fabricating a PWB (102, 402) with exposed copper pads (302), coating the copper pads with an organic solderability preservative (OSP) (404), depositing a solder paste that includes lead-free solder on the OSP covered copper pads (406), placing components (408) and heating the PWB above a liquidous temperature of the lead-free solder in an air atmosphere (410). The process allows very close spacing of components and component leads while forming reliable solder joints to components that are mechanically stressed and components that have non-negligible planarity or coplanarity tolerances.

REFERENCES:
patent: 5400221 (1995-03-01), Kawaguchi
patent: 5729896 (1998-03-01), Dalal et al.
patent: 6189203 (2001-02-01), Heinrich et al.
patent: 6457632 (2002-10-01), Teshima et al.
patent: 6479755 (2002-11-01), Kim et al.
patent: 6642485 (2003-11-01), Goenka et al.
patent: 6695200 (2004-02-01), Suzuki et al.
patent: 6698468 (2004-03-01), Thompson
patent: 6722028 (2004-04-01), Nakamura
patent: 6900383 (2005-05-01), Babb et al.
patent: 6902102 (2005-06-01), Tanabe et al.
patent: 2002/0067486 (2002-06-01), Forney et al.
patent: 2003/0081393 (2003-05-01), Yokoyama
patent: 2003/0175146 (2003-09-01), Yeh
patent: 2004/0020566 (2004-02-01), Cavallotti et al.
patent: 2004/0062015 (2004-04-01), Belopolsky
“Lead-Free Mandate Plumbs New Design Challenges”—Schweber, Bill; www.ednmag.com, Apr. 18, 2002.
“Fujitsu Develops Advanced Printing Bump Technology”—Fujitsu Laboratories; http://pr.fujitsu.com/en
ews/2001/12/12-1.html, Dec. 12, 2001.
“A Constitutive Model for Creep of Lead-Free Solders Undergoing Strain-Enhanced Microstructural Coarsening: A First Report”—Dutta, I; Journal of Electronic Materials, 2002.

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