Here is the abstract you requested from the HiTEN_2013 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.
|Evaluation of Refractory Metals for Package Level Interconnection in a Harsh Environment|
|Keywords: intercoonection, metallization, High temperature and pressure|
|Operating in a high temperature and pressure environment is a serious challenge for microelectronics device packaging. This study evaluates the electrical and mechanical behavior of Al, Ag, Mo, Nb and W metallization on ceramic substrates aged under harsh conditions, with the latter three showing great potential as candidates for replacing Cu. In the experiments, metals of interest were deposited by physical vapor deposition on alumina substrates. A stainless steel shadow mask was utilized to create electrical test structures. Metal to substrate adhesion was evaluated by means of pull test, while four point electrical test measurements were performed for electrical characterization. Samples were aged at 400°C and in 100 MPa argon pressure to simulate the harsh environment condition. During initial aging, it was observed that there was varying degree of electrical resistance changes. It can be understood that metal grains may grow during the initial thermal aging, leading to reductions in electrical resistance of some metals. Such reductions were observed on Ag and W samples. In comparison, there were much smaller increase in the measured resistances of Al and Mo. Nb shows the most significant increase in resistance that practically renders it unsuitable as an interconnect. Nb has been known to be somewhat reactive with alumina, which may lead to a thickness reduction of its electrical path. While Ag shows considerably weak metal-to-substrate adhesion, the other four metals show satisfactory post aging metal-to-substrates adhesion. From these results, considering the physical and electrical properties of the metal, Al, Mo and W could be good candidates for high temperature and pressure applications.|
|I Made Riko, Research Fellow
School of Materials Science and Engineering - Nanyang Technological University