THz-wave propagation characteristics of TSV-based transmission lines and interconnects

Transmission lines (T-lines) and interconnects are fundamental components for the millimeter-wave (mmW) and terahertz (THz) circuits. Based on the through-silicon via (TSV) technology, three T-lines, four different interconnects, and one substrate integrated waveguide (SIW) are developed and characterized over a frequency range up to 200 GHz. The results of T-lines show that coplanar waveguide (CPW) is almost with the lowest attenuation whereas microstrip line (MSL) suffers the highest insertion loss. As for the TSV-based interconnects, the 3-D transition from grounded CPW (GCPW) to CPW performs the lowest insertion loss up to 170 GHz. The electromagnetic shock wave is explored to analyze the results and physically explain the related phenomenon. SIW is inherently a good option for the TSV-based THz circuits. However, more research work should be carried out to reduce the high dielectric loss due to the low resistivity of silicon.