Here is the abstract you requested from the IMAPS_2009 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.
|New Plateable Thick Film Silver Conductors for DuPont™ Green Tape™ Low Temperature Co-fired Ceramic (LTCC)|
|Keywords: Plating, Electroless Ni/Au, LTCC|
|LTCC (Low Temperature Co-fired Ceramic) provides a technology option for designers that combine the benefits of HTCC and thick film technologies and is the technology of choice for many complex automotive, consumer, and military applications. Circuit cost is always a primary consideration. The traditional method employed to address material cost has been the use of mixed metallurgies, rather than all gold. Silver based conductors for signal and ground are utilized internally, with precious metal based transition via fill compositions that interconnect to gold conductors used for wire bonding or brazing, or other solderable conductors, externally. Plating external silver based conductors with electroless Ni/Au offers a reliable and lower cost alternative to the mixed metals approach. Some advantages of plating include; elimination of precious metal containing via fill compositions and gold external conductors, the use of a single metallurgy throughout the circuit, all resulting in additional cost reduction, and a smooth gold plated surface ideal for wire bond acceptance, or pin brazing. This paper introduces three new silver based thick film conductor compositions that are plateable with electroless Ni/Au for use with DuPont 951 Green Tape™. Reliability and performance are discussed in detail and include; 25 micron Au wire bonding, pin grid array brazing, and soldering. Data include thermal cycle/thermal shock evaluations, environmental performance using 85%RH/85ºC, and thermal aging.|
|Michael A. Skurski, Sr. Technical Service Specialist
DuPont Microcircuit Materials
Research Triangle Park, NC