M.I.C. Technology on Fused Silica Substrate: Ku Band Transponder Application

Circuits on alumina substrate suffer from electrical length reduction, this is a reason for choosing fused silica substrate with a lower dielectric constant. Organic dielectrics are generally not compatible with active device mounting in chip form as needed for mixers or amplifiers. An extensive study of different metallization process on fused silica substrates has been performed. Results are given for various thick films suppliers. Experimental characterization of microstrip lines was performed to obtain : ¿ eff, characteristic impedance and first order parasitic effects such as conduction losses and end capacitance. Different passive functions such as couplers and band pass filters have been analysed at X and Ku band. An application is a ground test transponder (14 - 11 GHz) which has been realized on silica substrate.