Here is the abstract you requested from the imaps_2018 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.
|Low Temperature Cure Polyamide Dielectric for RDL|
|Keywords: dielectric, RDL, polyamide|
|As FOWLP designs continue to evolve, higher pattern densities for Cu lines and interconnects continue to increase while thickness continues to decrease. Design targets such as these provide formidable challenges to dielectric redistribution layers (RDL) in the FOWLP design. As Cu densities increase the patterning resolution of the RDL dielectric needs to shrink to allow increased bump density, in turn this requires enhanced dielectric performance to minimize Cu migration issues. Minimizing mechanical stress continues to be a critical function of the RDL dielectric. Warpage leads to poor yields, distorting the planarity of the package and ultimately leading to stress induced failure from cracking and delamination. Reduction of the thermal budget is the primary means of reducing mechanical stress in FOWLP designs. The amount of Cu in the package continues to increase. Differences in thermal expansions of such and the dielectric increase with temperature. Further, conventional solder reflow processes and set points will continue to be used. Therefore, the RDL dielectric must continue to be thermally and mechanically stable, and capable of being cured at lower temperatures 180-200 �C to minimize overall mechanical stress from thermal expansion. We present a novel polyamide based RDL dielectric, KMRD, formulated to achieve current and future FOWLP design requirements. KMRD is a low temperature curable aqueous (2.38%TMAH) developable dielectric capable of meeting industry standards for mechanical and electrical requirements, with a high level of reliability while utilising a single stage cure at 185 �C. KMRD provides clear advantages over incumbent materials, with low temperature cure, improved pattern resolution, wide process latitudes, superior adhesion, chemical compatibility, and cost benefits using standard processing equipment and chemistry.|
|Daniel Nawrocki, Director of Development and Engineering