Manufacturing of miniaturised microsystems for low power wireless body-area-networks (BAN) medical applications-technological challenges and achievements

This paper brings into light the first prototype miniaturized system-in-package (SiP) Microsystems built for wireless body-area-network medical devices which mandate low power consumption and extreme packaging miniaturization. Specifically, this paper focuses on the first scenario for a 2D-SiP module for implantable demonstrators, namely cochlear and cardiac implants, with a passive antenna integrated on the device PCB next to the 2D-SiP module. The presented paper describes in detail all manufacturing steps for the realization of the 2D-SiP and all technology developments achieved to reach this goal. Firstly, a 3-layer SiP substrate has been successfully produced with 35μm ultra fine line copper structuring in conjunction with 70μm blind vias using semiadditive technology. Subsequently, assembly technologies for heterogeneous BAN components were further developed in order to achieve the placement of the tiny IF and RF SAW filters on the substrate and to implement mixed assembly of soldered passives with fluxed chip packages. Finally, the paper highlights the embedding technology employed in the project for the manufacturing of 2D-SiP modules on 9”x12” large panels. The module size is 4.2mm × 4.3mm × 0.77 mm.