Title :
High-Reliability RF-MEMS Switched Capacitors With Digital and Analog Tuning Characteristics
Author :
Grichener, Alex ; Rebeiz, Gabriel M.
Author_Institution :
Dept. of Electr. & Comput. Eng., Univ. of California at San Diego, La Jolla, CA, USA
Abstract :
This paper presents an RF microelectromechanical system switched-capacitor suitable for tunable filters and reconfigurable networks. The switched-capacitor results in a digital capacitance ratio of 5 and an analog capacitance ratio of 5-9. The analog tuning of the down-state capacitance is enhanced by a positive vertical stress gradient in the the beam, making it ideal for applications that require precision tuning. A thick electroplated beam (4-4.5 μm) results in Q greater than 100 at C-X-band frequencies, switching times of 30-50 μs, and power handling of 0.6-1.1 W. The design also minimizes charging in the dielectric, resulting in excellent reliability performance even under hot-switched and high-power (1 W) conditions.
Keywords :
capacitors; microswitches; RF microelectromechanical system switched-capacitor; analog capacitance ratio; analog tuning characteristics; digital capacitance ratio; digital tuning characteristics; down-state capacitance; high-reliability RF-MEMS switched capacitors; positive vertical stress gradient; power 0.6 W to 1.1 W; reconfigurable networks; thick electroplated beam; time 30 s to 50 s; tunable filters; Capacitance; Electrodes; Radio frequency; Springs; Stress; Structural beams; Switches; RF microelectromechanical systems (MEMS); Reconfigurable network; reliability; tunable capacitor; tunable filter;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2010.2065892
