Frequency extension of the fully printed phase shifter by paste composite optimization

This paper aims to propose new approaches based on fully screen printing technology for realization of tunable components with frequency extension based on BST paste composite optimization. The tunable phase shifters are fabricated to demonstrate the capabilities of these simple, flexible and low-cost methods. The proposed phase shifters contain tunable ferroelectric varactors in metal-insulator-metal (MIM) configuration, which are fully printed on top of an alumina carrier substrate with metallic and dielectric pastes, subsequently dried and cofired. The printed phase shifters work in different frequency ranges by using different ferroelectric composites. The BST pastes are optimized for low sintering temperature performance. Using BST composite with MgBO, the frequency range is extended to 7.6GHz.