CMOS biosensor using TSV interposer technology

This paper reports on the successful manufacture of metallized TSV interposer technology as a through molded via element in wafer level packaging of CMOS biosensors. The work has been executed by Silex Microsystems and Fraunhofer IZM, within the EU-consortium CAJAL4EU, where originally 29 partners were developing nanoelectronics-based biosensor technology platforms [1]. The finished metallized TSV interposers fabricated by Silex's 8" line were electrically characterized before molding and showed low resistance (mean resistance 10.3mΩ/Via, with Ï of 2.4) and a high yield of 99.6 %. The Chip in Polymer (CiP) reconfigured wafers were fabricated by IZM. The TSV interposers and CMOS biosensor chips die were interconnected using a PCB-based redistribution allowing lowcosi heterogeneous integrated packaging and separation between the active biosensor with wet I/Os and the dry electrical connections. The finished assembled package with the bio-sensor were optically inspected by X-ray CT, X-ray, cross sectioning and SEM. Preliminary results indicate that the complete molded module has an electrical contact, from top-bottom-top, with a resistance of 1-3O.