A new approach for system integrated packaging

As the number of applications for flexible assemblies is growing there is a lso a target variation of requirements for such packages. Therefore, differ ent technologies from CSP's to Smart Cards have been developed. This paper describes the results of the development of a new approach to wa fer-level redistribution as well as packaging concepts for. CSP's and embed ding of ultra-thin IC's into laminated substrates. The electrical interconn ection is made by fully-additive deposition of Cu lines. The technology is based on wet-chemical treatments which allow to avoid expensive vacuum proc esses and electroplating. A photo-sensitive epoxy material, commonly used i n printed circuit board manufacturing, was chosen as dielectric. Furthermor e the process implements electroless Ni deposition to protect the Al bondpa ds and to act as solder diffusion barrier on the Cu lines The technologies are presented together with the important parameters and the typical result s achieved. In order to evaluate the applicability of the processes develop ed, the reliability data of the obtained assemblies is presented and compar ed.