Design of circular plated curvature spring MEMS varactor with High Q Factor and low stress

Abstract

The communication circuits such as tuning circuit voltage controlled oscillator and other electronic circuits those required variable capacitor or varactor uses the semiconductor component such as P type Intrinsic N type PIN diode and Field Effect Transistor FET and Complementary Metal Oxide Semiconductor CMOS At lower frequency operation these semiconductor devices are good in performance But at the higher frequency of operation its performance is degraded The relation between voltage and capacitance is non linear Generally these semiconductor devices are operated by reverse bias voltage The increased reverse bias voltage increase the series resistance of the semiconductor devices The increase in the series resistance causes the high power loss it results in low quality factor High quality factor varactor is required for high performance The Micro Electro Mechanical System MEMS varactor consists of metal electrode on the other hand the semiconductor varactor is made up of semiconductor material The semiconductor varactor such as PIN diode CMOS devices have very high power losses because of its resistance At higher frequency operation these semiconductor devices not perform well due to its losses Various MEMS varactor design is available with various spring configurations The MEMS varactor generally consists of two metal plate one is fixed plate another one is movable plate The movement of the moveable plate is achieved by the spring arrangement Various spring configurations such as L spring T spring etc are available These MEMS varactor has low losses high quality factor and good capacitance ratio for higher Radio Frequency RF application newline