A novel wafer-level metal/BCB interconnection between both sides of wafer using TSV and its microwave performance

In this paper, a novel metal/BCB interconnection structure using through silicon via (TSV) to achieve integration on both sides of the Si wafer are proposed. It is composed of BCB/metal multilayers, high-resistivity silicon substrate with TSV. To reduce the transmission loss in microwave frequency, not only the high-resistivity silicon is used, but also a special TSV structure with the grounded shielding vias around the core via is adopted. Microstrip line (MSL) is used to transmit high-frequency signal on package plane together with the low-permittivity intermediate dielectric polymer, BCB. Descriptions on the interconnection structure and the process are included. The test vehicle, MSLs on both sides of the wafer connected by TSVs is measured up to 35GHz. The results of both the simulation and the measurement are presented. The results verify that the integration technology has a prospect in high-density wafer-level integration in microwave band.