Abstract: Heterogeneous Integration provides a powerful and cost-effective means for building complex Systems-in-Package (SiPs). Recently, sophisticated examples of heterogeneously integrated packages containing nearly 50 dies, many fabricated by different vendors on different technological nodes, have been demonstrated. In general, integration of large number of dies leads to a polynomial increase in material interfaces, which are potential locations for increased thermal resistance and mechanical fracture. Also, the larger sized multi-die packages result in complex chip-package interactions, while the smaller solder bump size results in joints that are largely made of brittle intermetallic compounds.
In this talk, I will describe selected reliability concerns in heterogeneously integrated packages and illustrate through examples the thermo-mechanical behavioral characterization necessary for their reliability assessment. Specifically, I will describe package-caused fracture in back-end-of-line (BEOL) structures and modeling and experimental characterization of phase growth under current and elevated temperature (electromigration) in microbumps. Underlying the examples are sophisticated multiphysics computational models for moving (crack or phase) boundaries as well as fabricated test devices.
Bio: Ganesh Subbarayan is the James G. Dwyer Professor of Mechanical Engineering at Purdue University and the Co-Director of the Purdue-Binghamton SRC Center for Heterogeneous Integration Research in Packaging (CHIRP). He also serves as the Director of the recently created Atalla Institute for Advanced System Integration and Packaging (ASIP) at Purdue University. He holds a B.Tech degree in Mechanical Engineering (1985) from the Indian Institute of Technology, Madras and a Direct Ph. D. (1991) in Mechanical Engineering from Cornell University.