Characterization of TSV-Induced Loss and Substrate Noise Coupling in Advanced Three-Dimensional CMOS SOI Technology

Abstract

Electrical loss and substrate noise coupling induced by through-silicon-vias (TSVs) in silicon-on-insulator (SOI) substrates is characterized in frequency and time domains. A three-dimensional (3-D) test site in 45-nm CMOS SOI including copper-filled TSVs and microbumps ( μC4's) is fabricated and measured to extract the interconnect loss. Good correlation to the electrical circuit models is demonstrated up to 40 GHz. In addition to a buried oxide layer, a highly doped N+ epilayer used for deep trench devices in 22-nm CMOS SOI is considered in full-wave electromagnetic simulations. Equivalent circuit models are extracted to assess the impact of noise coupling on active circuit performance. A noise mitigation technique of using CMOS process compatible buried interface contacts is proposed and studied. Simulation results demonstrate that a low-impedance ground return path can be readily created for effective substrate noise reduction in 3-D IC design.