In this paper we present a technology developed for reliable electrical interconnection on film substrates and between vertically stacked film layers. Applying through-hole via technologies for 3D foil stacks enables multi-functionality and RF performance combined with open form-factor and very cost-efficient manufacturing of conformable electronic modules. The manufacture of fine line metal patterns (line /space geometries below 20μm) on film substrates is performed by cost-effective roll-to-roll technology. Furthermore procedures and technologies for handling and lamination of film based sub-modules have been developed. Also the manufacture and handling of ultra-thin and flexible integrated circuits has been combined with placement of SMD type passive and with integrated printed passive components in the same technology.