Laminated solder column

Details Laminated solder column Laminated solder column

1995-08-07

1997-06-24

Crane, Sara W.

Active solid-state devices (e.g., transistors, solid-state diode

Combined with electrical contact or lead

Bump leads

257738, 257772, H01L 2348

Patent

active

056419902

ABSTRACT:
A method for forming solder balls and an apparatus and method for forming solder columns on the electrical contact pads of an electronic package in order to establish a more reliable electrical and mechanical connection between an electronic package and a printed circuit board. In one embodiment, solder balls are formed on the electrical contact pads of a package by placing solder cylinders over the electrical contact pads and then passing the package through a reflow furnace where the solder cylinders take the form of spheres and are wetted onto the pads. In a second embodiment, a laminated solder column is formed that is resistant to collapse during the manufacturing process. The laminated solder column comprises a solder cylinder being clad on its top and bottom surfaces with a solder material having a lower melting temperature than that of the center solder cylinder. When attaching the solder column to a package or a printed circuit board reflow temperatures are maintained above the melting temperature of the cladding material but below the melting temperature of the center solder cylinder such that the cladding is wetted onto the electrical contact pads of the package or printed circuit board while the center solder cylinder maintains its solid form.

REFERENCES:
patent: 3292240 (1966-12-01), McNutt et al.
patent: 3303393 (1967-02-01), Hymes et al.
patent: 3436818 (1969-04-01), Merrin et al.
patent: 3486223 (1969-12-01), Butera
patent: 3512051 (1970-05-01), Noll
patent: 3811186 (1974-05-01), Larnerd et al.
patent: 3839727 (1974-10-01), Herdzik et al.
patent: 3921285 (1975-11-01), Krall
patent: 4545610 (1985-10-01), Lakritz et al.
patent: 4673772 (1987-06-01), Satoh et al.
patent: 4693770 (1987-09-01), Hatada
patent: 4752027 (1988-06-01), Gschwend
patent: 4818728 (1989-04-01), Rai et al.
patent: 5075965 (1991-12-01), Carey et al.
patent: 5130779 (1992-07-01), Agarwala et al.
patent: 5186383 (1993-02-01), Melton et al.
patent: 5269453 (1993-12-01), Melton et al.
patent: 5317191 (1994-05-01), Abe
Caufield, T., et al., Ceramic Ball Grid Arrays--Ceramic Column Grid Arrays, IBM -- SEMICON Conference, San Francisco, CA., Jun. 1993, 28 pages.
V.D. Coombs, IBM Technical Disclosure Bulletin, vol. 16, No. 3, p. 767 (Aug. 1973).

Affiliated with

Also associated with

Rating

Laminated solder column does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Laminated solder column, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Laminated solder column will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-150636