High performance electrically tunable RF phase shifter with application of PZT and nano-patterned permalloy thin films

Many approaches have been investigated to achieve tunable phase shifters, such as MEMS technique, varactors and PIN diode. However, MEMS technique significantly increases the fabrication complexity and has difficulty in integrating. Tunable phase shifters with varactors and PIN diode require extra components which increases the size of the phase shifters. Ferroelectric and ferromagnetic material have been widely explored and utilized in the tunable phase shifters. In this paper, based on the step impedance coplanar waveguide (CPW) transmission line slow wave structure, both Lead Zirconium Titanate (PZT) and nano-patterned Permalloy thin film are integrated to achieve a fully electrically tunable phase shifter with both capacitive and inductive tunability with DC voltage and DC current respectively.