BaSrTiO 3 Interdigitated Capacitors for Distributed Phase Shifter Applications

Abstract-In this letter, BaSrTiO 3 (BST) interdigitated capacitors on sapphire substrates have been investigated. The tunability and quality factor of interdigital capacitors has been optimized for microwave and millimeter wave applications. A monolithic K-band phase shifter circuit that employs voltage tunable BaSrTiO 3 (BST) interdigitated capacitors is presented here. Index Terms-BaSrTiO 3 , distributed phase shifter, interdigital

Monolithic Ka-band phase shifter using voltage tunable BaSrTiO3 parallel plate capacitors. Microwave and Guided Wave Letters

Abstract-A monolithic Ka-band phase shifter circuit that employs voltage tunable BaSrTiO 3 (BST) parallel plate capacitors is presented here. The circuit is capable of continuous 0 -157 phase shift at 30 GHz with an insertion loss of only 5.8 dB and return loss better than 12 dB. In addition to promising loss performance (27.1 /dB) at 30 GHz, the circuit reported here has several advantages over previously reported BST phase shifters such as moderate control voltages (20 V), room temperature operation, and compatibility with monolithic fabrication techniques