High-performance epoxy/binary spherical alumina composite as underfill material for electronic packaging. (March 2019)

• Record Type: Journal Article
• Authors: Chen, Chao; Xue, Yang; Li, Xiongwei; Wen, Yingfeng; Liu, Jinwei; Xue, Zhigang; Shi, Dean; Zhou, Xingping; Xie, Xiaolin; Mai, Yiu-Wing
• Is Part Of: Composites. Volume 118(2019)
• Page Start: 67
• Page End: 74
• Publication Date: 2019-03
• Subjects: A. Polymer-matrix composites -- B. Thermal properties -- B. Mechanical properties -- D. Rheology; Composite materials -- Periodicals; Manufacturing processes -- Periodicals; Composite materials; Manufacturing processes; Periodicals; 620.11805
• DOI: 10.1016/j.compositesa.2018.12.019
• Languages: English
• ISSNs: 1359-835X

Abstract

Abstract: In this study, epoxy (EP)/binary spherical alumina (S-Al2 O3 ) composites with a high loading of 50 vol% were fabricated by incorporating different sizes of S-Al2 O3 into EP to increase the thermal conductivity and yet retain the flowability of the composites. Notably, a distinctly reduced viscosity (21.8 Pa·s) and a highly increased thermal conductivity (1.364 W/m·K) were achieved by a binary S-Al2 O3 mixture with 80% 30 μm and 20% 5 μm alumina that would have a theoretical maximum packing volume, thus permitting larger available free volume for the motion of particles and hence reducing the friction between them. Also, these EP/S-Al2 O3 binary composites possessed superior electrical insulation, high thermal stability, significantly reduced thermal expansion coefficient and good mechanical properties. These combined desirable properties indicate that binary S-Al2 O3 mixtures with an optimized size distribution and maximum packing volume are best candidates to develop high-performance epoxy-based underfill materials which would improve the flip-chip reliability.