Influence of Pad Shape on Self-Alignment in Electronic Packaging
Authors: Ahn, Do H.; Lee, Jihye; Yoo, Choong D.; Kim, Yong-Seog
Source: Journal of Electronic Materials, Volume 35, Number 3, March 2006 , pp. 411-415(5)
Abstract:Anisotropic self-alignment of the noncircular pads is investigated to reduce the misalignment in electronic packaging, and the effects of the direction and length ratio of the noncircular pads are analyzed. The restoring forces of circular and noncircular pads are calculated numerically using the surface evolver and are compared with the experimental data. The restoring force in the minor-axis direction of the noncircular pad becomes largest followed by the circular pad and the major-axis direction of the noncircular pad. Directionality increases with the length ratio, which implies that more accurate alignment can be achieved in the specific direction.
Document Type: Regular Paper
Publication date: 2006-03-01