Process development of thick Si interposer for 2.5D integration of RF MEMS devices

In this paper, a thick TSV interposer with integrated inductor, micro-strip and coplanar waveguides(CPW) transmission lines on high resistivity Si substrate is presented for 2.5 D integration of RF devices. The electrical interconnection through Si interposer is realized by two individual pieces of holly Cu TSVs of different diameters assembled at the axis. Metallization is realized with a redistribution layer of Cu on the each side. The process is developed to fabricate TSV interposer on thick high resistivity Si wafer. It's featuring in no need of Cu CMP process. Thick Si interposer sample integrated passives such as inductor, CPW transmission line and micro-strip transmission line is fabricated on high resistivity Si substrate.