A RADIO FREQUENCY MEMS UNIT CELL MINIATURE-SIZE SWITCHED CAPACITOR BASED PHASE SHIFTER DEVICE

摘要

A process for making a radio frequency MEMS unit cell miniature-size switched capacitor based phase shifter device (1) is disclosed. The process comprises of cleaning a silicon wafer (3), oxidizing it by thermal oxidation process to obtain a layer of silicon dioxide on the wafer surface and depositing a thin layer of aluminium by thermal evaporation. Thereafter, patterning is done to obtain a coplanar waveguide (CPW) pattern and a thin layer of silicon nitride (Si3N4) is deposited in the manner such as described such that a capacitive contact between a plurality of bridges (4a) and the central conductor of a CPW line (2) is achieved. Next, in a single step, fixed anchors (5) are formed as end supports for the bridges (4a) and a sacrificial layer Is patterned for supporting the bridges (4a) from the bottom. Thereafter, a thin layer of Cr-Au layer is deposited to generate a bridge pattern. This is followed by removing the sacrificial layer for releasing the bridges (4a) and finally soaking the device in a solvent and then drying it. The invention also discloses a device made by the process.