Integrated resistive bias network for tunable devices on ferroelectric ceramics

A simple and low cost method is presented for integrating resistive bias network for tunable microwave devices, especially on ferroelectric films. The high resistive bias network is made of the existing adhesive layer that is usually necessary for the metalization process on ferroelectric films. Due to that, an additional material deposition process for this network is saved. A tunable phase shifter based on a coupled microstrip line filter topology demonstrates the capability and benefits of the high resistive biasing. A screen printed Barium-Strontium-Titanate (BST) thick films is used as the tunable material.