Fine Pitch Flip Chip Attach to a Flexible Carrier

An advanced assembly process has been developed to accommodate 150um pitch flip chip attach to a flexible carrier. The challenges involved in designing the flexible carrier to accommodate a fine pitch solder bumped die will be discussed. A new and innovative hot bar thermode attach process that can accommodate very large die has been developed. In this process, a very tight control of the standoff is maintained in order to effectively underfill the very large attach region. Data will be presented to show the ability of the process to yield complete fine pitch flip chip attach for the large die evaluated in this work. In addition, reliability data will be presented.