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Defects such as voids or seams are frequently found in TSV via filling process.To achieve defect-free copper via filling, organic additives such as suppressor, accelerator and leveler were necessary in a copper plating bath. However, by-products stemming from the breakdown of these organic additives reduce the lifetime of the devices and plating solutions. In this research, the effects of levelers on copper electrodeposition were investigated without suppressor and accelerator to lower the concentration of additives. Threelevelers(janus green B, methylene violet, diazine black) were investigated to study the effects of levelers on copper deposition. Electrochemical behaviors of these levelers were different in terms of deposition rate. Filling performances were analyzed by cross sectional images and its characteristics were different with variations of levelers.

Hydroforming and Deep Drawing represent leading technologies for forming sheet metal components. The Materials Branch of the University of Duisburg-Essen works since more than 10 years in the field of Hydroforming and showed that Hydroforming increases the strength and that the weldings of hydroformed tubes normally exhibit a same (fatigue) strength as the base material. For an improvement of the economics of hydroforming spliced tubes were considered and standard hollow nodes for tubes nodes structures were developed and a proposal was made to produce these tubes in variable tools with segments or lamellas.A significant increase in economics of Hydroforming and of Deep Drawing of components is achieved by an introduction of the principles of an integral (cooperative) development of products. At the University of Duisburg-Essen the following stages are run through: CAD (the Material Branch uses PRO/ENGINEER J ), forming simulation -for that PAM-STAMP J (ESI) and PATRAN MARC MENTAT J (MSC) are used -FEM strength calculation and EVICD for a consideration of variable service loading.Forming simulation needs as basic material data the yield curve, the parameters of anisotropy and the Forming Limit Curve (FLC). For a determination of the FLC in Deep Drawing Tests suitable Nakazima specimens were developed by applying the principles of cooperative product development. The specimens could then successfully be validated in Deep Drawing Tests, which were instrumented by the advanced 3D-forming-analysis-system AUTOGRID inProcess (VIALUX). Various other forming simulations were also performed and some general rules for the performance of forming simulations were formulated. Finally, reverse engineering is briefly discussed.

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