Computational Physics Group
Microstructure Statistics--Property Relations of Silver Particle--Based Interconnects
A. Gillman1, M.J.G.H. Roelofs2, K.
Matous1, V.G. Kouznetsova2,
O. van der Sluis2,3, and M.P.F.H.L. van Maris2
1Department of Aerospace and Mechanical Engineering,
University of Notre Dame,
Notre Dame, IN, 46556, USA.
2Department of Mechanical Engineering,
Eindhoven University of Technology,
Eindhoven, The Netherlands.
3Philips Research Laboratories,
High Tech Campus 4, 5656 AE,
Eindhoven, The Netherlands.
This paper presents a novel approach for establishing microstructure statistics-property relations for a silver particle-based thermal interface material (TIM). Several sintered silver TIMs have been prepared under different processing conditions, generating samples with distinct microstructures. The 3D microstructure is revealed and visualized using the combination of Focused Ion Beam (FIB) milling and Scanning Electron Microscopy (SEM) imaging. Representative synthetic model microstructures have been generated based on Gaussian random field models, having well defined analytical description. The statistical characteristics of the samples and the synthetic models are shown to have a good correspondence, indicating that the linear effective properties of these complex materials can be predicted based on analytical estimates available for the synthetic models. This is verified by computing the effective elastic and thermal material properties using the computational homogenization approach based on the finite element models of the real samples. The computational homogenization, providing the reference solution, and the higher-order statistical estimates for the synthetic models are in very good agreement. These results can be used in the development of new silver particle-based materials, whereby the expensive and time consuming effective material property characterization can be replaced by efficient estimation based on the synthetic random field models.
In this paper, a methodology for establishing microstructure statistics-property relations has been presented and applied to a sintered silver particle-based interconnect material for high power electronic applications. The novel original feature of this approach is the combination of the statistical morphological measures of real and synthetic microstructures with the higher order statistical micromechanics and direct finite element computational homogenization. The main steps and conclusions of this contribution can be summarized as follows.
The authors are grateful to Dr.
Sebastian Fritzsche from Heraeus for providing the
materials for this study. This work was partially
supported by the NANOTHERM project co-funded by the
European Commission under the "Information and
Communication Technologies", Seven Framework Program,
Grant Agreement No 318117.
Download paper here.
© 2017 Notre Dame and Dr. Karel Matous