Coplanar waveguides on silicon substrate with thick oxidized porous silicon (OPS) layer

The problem of high dielectric loss of waveguide on silicon in the microwav e region can be solved by utilizing a thick silicon dioxide layer that is f ormed by silicon substrate anodization and oxidation processes. Coplanar wa veguides (CPW's) are fabricated on silicon substrate with a 20-mu m-thick o xidized porous silicon (OPS) layer and demonstrate very high performance of 0.1-dB/mm attenuation at 4 GHz, Thus, the OPS process is promising for gig aherz applications of silicon substrates.