Dually Electrically Tunable 3-D Compact RF Phase Shifter

Abstract

An electrically tunable radio frequency phase shifter with compact 3-D structure that integrates both ferromagnetic and ferroelectric materials, and utilizes 3-D structure to increase the tuning efficiency and achieve miniaturization.

What is claimed is: 
     
         1 . An electrically tunable phase shifter comprising:
 wherein the electrically tunable phase shifter has dual tunability;   wherein the electrically tunable phase shifter has continuous tunability;   wherein the tunable phase shifter further comprises both ferromagnetic and ferroelectric materials;   wherein the electrically tunable phase shifter is comprised of 3-D lumped elements; and   wherein the electrically tunable phase shifter further comprises at least one tunable solenoid inductor and at least one tunable capacitor.   
     
     
         2 . The electrically tunable phase shifter of  claim 1 , wherein when phase is tuned over a range impedance is kept constant. 
     
     
         3 . The electrically tunable phase shifter of  claim 1 , wherein the at least one tunable solenoid comprises Permalloy. 
     
     
         4 . The electrically tunable phase shifter of  claim 3 , wherein the Permalloy comprises a nickel-iron magnetic alloy. 
     
     
         5 . The electrically tunable phase shifter of  claim 1 , wherein the at least one tunable capacitor comprises lead zirconate titanate (PZT). 
     
     
         6 . The electrically tunable phase shifter of  claim 5 , wherein the at least one tunable capacitor comprises a structure of metal-insulator-metal. 
     
     
         7 . The electrically tunable phase shifter of  claim 1 , wherein the phase shifter is tuned fully electrically by DC current and DC voltage simultaneously or separately without introducing extra an biasing network. 
     
     
         8 . The electrically tunable phase shifter of  claim 1 , wherein length normalized phase tenability is up to at least 210 degree/cm. 
     
     
         9 . The electrically tunable phase shifter of  claim 1 , wherein equivalent characteristic impedance of the phase shifter is substantially constant via providing selectively DC biasing conditions. 
     
     
         10 . The electrically tunable phase shifter of  claim 1 , wherein the at least one tunable solenoid inductor comprises a thin film enabled tunable 3-D solenoid inductor. 
     
     
         11 . The electrically tunable phase shifter of  claim 1 , wherein the phase shifter includes both inductive and capacitive tenability. 
     
     
         12 . A method of forming an electrically tunable phase shifter comprising:
 fabricating at least one bottom electrode comprising a Pt/Ti bilayer;
 wherein Ti and Pt are deposited and patterned employing e-beam evaporation and lift-off; 
   fabricating at least one MIM capacitor comprising a PZT film;
 wherein a PZT precursor is prepared with a sol-gel method; 
 wherein the PZT precursor is spin-coated on a substrate; 
 wherein the resulting PZT film is crystallized; 
 wherein the PZT film is patterned via wet-etching; 
   fabricating at least one solenoid inductor;
 wherein a silicon substrate is patterned with at least a first Py layer and a first Au layer; 
   fabricating at least one top electrode of PZT enabled MIM; and   depositing Au and patterning with lift-off method to complete the at least one top electrode layer and the at least on MIM capacitor.   
     
     
         13 . The method of  claim 12 , wherein the at least one tunable solenoid comprises Permalloy. 
     
     
         14 . The method of  claim 13 , wherein the Permalloy comprises a nickel-iron magnetic alloy. 
     
     
         15 . The method of  claim 12 , wherein the phase shifter is tuned fully electrically by DC current and DC voltage simultaneously or separately without introducing extra an biasing network. 
     
     
         16 . The method of  claim 12 , wherein length normalized phase tunability is up to at least 210 degree/cm. 
     
     
         17 . The method of  claim 12 , wherein equivalent characteristic impedance of the phase shifter is substantially constant via providing selectively DC biasing conditions. 
     
     
         18 . The method of  claim 12 , wherein the at least one solenoid inductor comprises a thin film enabled tunable 3-D solenoid inductor. 
     
     
         19 . The method of  claim 12 , wherein the phase shifter includes both inductive and capacitive tunability.