Characteristics of 10–110GHz Transmission Lines on Fused Silica Substrate for Millimeter-wave Modules

With the development of millimeter-wave (mm-W) wireless communication, the pursuit for high electrical performance package material is crucial. Fused silica is a promising material for ultra-high frequency application due to the excellent electrical properties, higher integration and higher density interconnects. In this paper, the microstrip ring resonators (MRRs) with different radius are fabricated on 6 inch fused silica wafer with 200µm thickness to obtain the dielectric constant from 10GHz to 100GHz. In addition, conductor-backed coplanar waveguide (CBCPW) with a length of 10mm is also designed, fabricated and measured. The measured insertion loss is 0.05dB/mm at frequency of 40GHz and 0.23dB/mm at frequency of 110GHz, which means that fused silica is an ideal substrate for mm-W modules.