Hi Ruby,
Yes, there are some concerns about PTVs partially filled with solder. The
transition from solder-filled to non-solder-filled produces a stress riser in
the Cu PTV barrel walls. This is of no practical concern for applications for
which the thermal cyclic environment is not severe; for severe environments,
e.g., automotive, military, some satellites, this stress riser can be
enoughto cause premature failure.

Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability Consulting
7 Jasmine Run
Ormond Beach, FL  32174  USA
Phone: 904-437-8747, Fax: 904-437-8737
E-mail: [log in to unmask], Website: www.engelmaier.com

In a message dated 6/28/00 11:19:14, [log in to unmask] writes:
>Hello all:
>We try to fully or partially fill the via holes (<0.025" diameter) with
>solder due to the process. I'm wondering that if there are some concerns
>(such as fatigue).
>Any information are very welcome. Thanks a lot!
>R.H.

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