Low Cost High Performance Phased Array Antennas with Beam Steering Capabilities

摘要

In this report, we focused on fabricating the tunable ferroelectric phase shifter and verifying the simulation results with the fabricated device. To achieve low loss and high tunable characteristics of BSTO, the RF vacuum sputtering technique has been used and we investigated effects of sputtering parameters such as substrate temperature, sputtering pressure, and gas mixture ration on properties of BSTO. Optimal sputtering conditions for BSTO deposition were determined based on epitaxial qualities characterized by the RBS- channeling spectrometry, which will be discussed in later part of the report. Using the optimized sputtering parameters, various sets of BSTO films have been deposited on different substrates and various size of CPW phase shifters have been fabricated on the BSTO layer using lift-off process. RF performances of the fabricated ferroelectric CPW phase shifters were characterized by using on- wafer probe station connected to a vector network analyzer. The fabrication procedures of ferroelectric phase shifters are described and the experimental measurement data are compared with simulated results for verification.