Here is the abstract you requested from the IMAPS_2010 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.
|A Novel Metal Core Substrate with Simplified Manufacturing Process and High Adhesion Conformal Dielectric and Circuitry Metal for High Density Chip-Scale Packaging Applications|
|Keywords: metal core, substrate, RF packaging|
|Substrates play a critical role in the quality and reliability of electronic packages and systems. Metal core substrates provide opportunities with respect to strength, heat dissipation, and speed over common organic substrates. The metal core provides an opportunity for in grounding enhancements in RF circuits. This paper presents the results of the development of a metal core substrate design which has advantages over conventional competitive designs. The manufacturing flow developed in this work has fewer process steps, uses fewer materials and shows above required interfacial adhesion strength. The work outlines material evaluations to enhance the interfacial adhesion and corrosion resistance. The results of the evaluation of mechanical, chemical, and other methods to enhance interfacial adhesion are presented and compared. The enhanced interface shows 80% adhesion increase for the circuitry metal over and beyond IPC requirement. This work successfully reduced the amount of processing steps necessary and the number of materials used in the construction and manufacture of the substrate. Thus, the improved processing and stack-up provides not only quality and reliability advantages but also reduces cost and increases throughput. An adhesion layer has been identified over the core for Al and Invar metal cores which provides dielectric adhesion to the core much above the value required by the industry. The adhesion layer also shows corrosion resistance advantages. Corrosion susceptibility of the core was evaluated optically after highly accelerated stress testing (HAST). The samples were optically evaluated after 96 hours at 121°C temperature and 0.1 MPa pressure. An adhesion layer between the dielectric and circuitry metal has been identified which provides an adhesion value between the circuitry copper metal and the dielectric much above required by industry requirements. Successful etching of the circuitry layer has been demonstrated using RIE process for circuitry development over the dielectric.|
|Syed Sajid Ahmad, Manager of Engineering Services
North Dakota State University; Center for Nanoscale Science and Engineering; Center for Nanoscale Science and Engineering