Grant
In terms of reliability I wouldn't bother too much. Cracks in the
solderings of ceramic chip-components grow along the pad and along the
cap in the meniscus. Both have different sources.
- Cracks along the pad grow due to thermal mechanical stress caused by
the CTE- difference of PCB and component
- Cracks along the cap in the meniscus grow due to the CTE-difference
of component and solder.
The advantage of a meniscus is the longer distance a crack along the
pad has to grow until an open occurs. However this is only theoretical
since the perpendicular crack along the cap meets the one along the pad
sooner than the latter will come to the end of the meniscus. Therefore
I would dare to say that the lack of a meniscus is not a big risk. And
anyway if the reliability of your product relies on the few cycles one
could win by having a meniscus I wouldn't sleep well in your place.
Best regards
Guenter
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