The paper reports about investigations on the chip on glass (COG) bonding process using anisotropic conductive films (ACF). Experimental methods as well as theoretical analyses, by both analytical and numerical means, are applied. The assumptions concerning the thermo-mechanical and rheological properties of the polymer materials involved in the bonding process are shortly characterized in dependence on temperature. The transient development of the temperature field during the bonding process is studied by finite element (FE) analysis in dependence on the upper and lower chuck temperatures. Analytical techniques of fluid mechanics are used to predict the flow of the conductive particles during bonding, treated as dimensionless points embedded in a viscous matrix. This analytical description allows to estimate the number of conducting particles on a bump of a chip after bonding. Furthermore, numerical calculations are applied to characterize the influence of viscosity gradients on the particle flow. Finally, nonlinear finite element simulations are used to investigate the stress development and stress relaxation process within the ACF joints.Index Terms-Analytical adhesive flow model, anisotropic conductive films, FE-modeling, flow analysis, thermo-mechanical analysis.

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The realization of light weight design of components with local, load adapted properties is a major goal in the development of new manufacturing and processing methods of metal composite materials. A main challenge in the manufacturing of compounds by forming consists in the realization of the necessary conditions for the initiation of the diffusion process and the generation of metallic bonding. A combination of high contact tensions with specific forming conditions such as temperature distribution and surface enlargement is required in order to initiate the diffusion of atoms during the forming process. The article presents FEM-simulation and investigation of contact and forming conditions of aluminum-magnesium composites with respect to an incremental forming method. The characteristics of the compound materials, surface enlargement and local forming conditions as well as temperature gradients are important factors for the diffusion processes. The investigation of co ntact conditions during compound formation is a prerequisite for the further design of forming methods and the base for new approaches of generating composites of two light metal alloys into products with favorable properties such as high specific strength and corrosion resistance

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