Abstract
ABSTRACT Our research group has recently demonstrated the operation of ferroelectric varactor shunt switches. The device operation is based on the nonlinear dielectric tunability of a barium strontium titanate (BST 60/40) thin-film sandwiched between two metal layers in a parallel plate configuration. A 4:1 change in the varactor capacitance has been achieved with a bias voltage < 10 V, through optimization of the nanostructured BST thin-film fabrication process on high resistivity Si substrates. In this work, we investigated the varactor shunt switches for broadband phase control applications. Varactor shunt switches and cascaded shunt switches were used for phase control circuits, due to the large phase shifts possible as a result of the dc bias dependent tunability of the varactor. The differential phase shift can be defined as the difference between the phase of S21 at a dc bias voltage and zero-bias. The measured differential phase shift for a single varactor shunt switch was 30 ± 2 degrees between 8 and 26 GHz at 8 V dc bias. A cascaded varactor shunt switch resulted in a differential phase shift of 110 degrees ± 10 degrees over the bandwidth of 20 and 31 GHz.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
