110-150 GHz Permittivity Extraction of Silicon Substrate in 3D TSV-MEMS Process

This paper presents a broadband method for extracting the dielectric constant with grounded coplanar waveguide (GCPW). The extracting structures are designed and under fabrication in 3D TSV-MEMS process. Thru-reflect-line (TRL) technique is applied to obtain the scattering parameters of device under test (DUT). Based on characteristic analysis and related analytical formulas of GCPW, the relative dielectric constant of the silicon substrate is calculated from 110 GHz to 150 GHz. The proposed method, which derives results in good agreement with preset values, is a good candidate for permittivity extraction at millimeter-wave (mmW) and even terahertz (THz) frequencies.