Here is the abstract you requested from the IMAPS_2007 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Dimensional Changes in LCP SMT DIMM Connectors and the Effect on Circuit Card Flatness|
|Keywords: Reliability, PCB Assembly, Interconnect|
|Circuit cards assembled with SMT DIMM connectors molded from various commercially-available LCP resins were found to exhibit inordinate warp and distortion following solder reflow. Card warp resulted in excessive strain on the solder connections thereby decreasing joint reliability. No connector warp through thermal cycling was observed in loose piece connectors. Raw card warp through thermal cycling was observed and noted to be opposite the direction of warp of the completed card assembly thus indicating a significant shape-change effect of the card/connector interface. Assembled card warp was driven both by a mismatch in the CTE between the card and the connectors as well as significant dimensional changes in the connector housings as the card was passed through a conventional reflow process. Connectors molded from LCP were found to exhibit elongation along the major axis following a thermal anneal process.|
|Amanda Mikhail, Advisory Engineer, Interconnect Development