Active solid-state devices (e.g. – transistors – solid-state diode – Lead frame
Reexamination Certificate
2006-04-04
2006-04-04
Parekh, Nitin (Department: 2811)
Active solid-state devices (e.g., transistors, solid-state diode
Lead frame
C257S787000, C257S784000, C257S730000
Reexamination Certificate
active
07023074
ABSTRACT:
Methods of fabricating leadless packages are described that provide good solder joint reliability. In most respects, the packages are fabricated in a manner similar to current lead frame based leadless packaging techniques. However, at some point in the process, the contacts are provided with undercut regions that are left exposed during solder plating so that the solder plating also covers the exposed side and undercut segments of the contacts. When the resultant devices are soldered to an appropriate substrate (after singulation), each resulting solder joint includes a fillet that adheres very well to the undercut portion of contact. This provides a high quality solder joint that can be visually inspected from the side of the package.
REFERENCES:
patent: 5998234 (1999-12-01), Murata et al.
patent: 6083776 (2000-07-01), Manteghi
patent: 6191494 (2001-02-01), Ooyama et al.
patent: 6229200 (2001-05-01), Mclellan et al.
patent: 6242281 (2001-06-01), Mclellan et al.
patent: 6278618 (2001-08-01), Lee et al.
patent: 6372539 (2002-04-01), Bayan et al.
patent: 6399415 (2002-06-01), Bayan et al.
patent: 6400004 (2002-06-01), Fan et al.
patent: 6410363 (2002-06-01), Tani et al.
patent: 6448107 (2002-09-01), Hong et al.
patent: 6511863 (2003-01-01), Farnworth et al.
patent: 6603194 (2003-08-01), Utsumi et al.
patent: 6617197 (2003-09-01), Bayan et al.
patent: 6723585 (2004-04-01), Tu et al.
patent: 6777800 (2004-08-01), Madrid et al.
patent: 6797540 (2004-09-01), Li et al.
patent: 6838757 (2005-01-01), Abbott et al.
patent: 2001/0030355 (2001-10-01), Mclellan et al.
patent: 2003/0230792 (2003-12-01), Wu et al.
patent: 2004/0207054 (2004-10-01), Brown et al.
patent: 2000-294719 (2000-10-01), None
U.S. Office Action mailed Aug. 27, 2004, from U.S. Appl. No. 10/316,788.
Bayan Jaime A.
Hu Ah Lek
Li Felix C.
Nadarajah Santhiran
Beyer Weaver & Thomas LLP
National Semiconductor Corporation
Parekh Nitin
LandOfFree
Enhanced solder joint strength and ease of inspection of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Enhanced solder joint strength and ease of inspection of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Enhanced solder joint strength and ease of inspection of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3607400