As the basic building block of microwave and millimeter wave units and circuits, the microwave switch must fulfill several requirements including low insertion loss, high isolation and small dimensions. For conventional electrostatically actuated microwave MEMS switches, the isolation between DC and RF is achieved using an RF choke. In this invention, a miniature electrostatically actuated microwave switch with a cantilever and employing two resistive lines on a first substrate and act as the actuation electrodes is provided. The resistive lines as the actuation electrodes according to this invention allows one to minimize the switch dimensions, to facilitate the integration and minimize the interference of the propagating microwave or millimeter wave signals. Another feature of this invention is a miniature electrostatically actuated microwave switch with a cantilever and employing two resistive lines as actuation electrodes on a first substrate, and a third resistive line on a second substrate for the de-actuation of the cantilever.

A RF MEMS switch comprising a crossbeam of SiC, supported by at least one leg above a substrate and above a plurality of transmission lines forming a CPW. Bias is provided by at least one layer of metal disposed on a top surface of the SiC crossbeam, such as a layer of chromium followed by a layer of gold, and extending beyond the switch to a biasing pad on the substrate. The switch utilizes stress and conductivity-controlled non-metallic thin cantilevers or bridges, thereby improving the RF characteristics and operational reliability of the switch. The switch can be fabricated with conventional silicon integrated circuit (IC) processing techniques. The design of the switch is very versatile and can be implemented in many transmission line mediums.

The invention provides a liquid cell for an atomic force microscope. The liquid cell includes a liquid cell housing with an internal cavity to contain a fluid, a plurality of conductive feedthroughs traversing the liquid cell housing between the internal cavity and a dry side of the liquid cell, a cantilevered probe coupled to the liquid cell housing, and a piezoelectric drive element disposed on the cantilevered probe. The cantilevered probe is actuated when a drive voltage is applied to the piezoelectric drive element through at least one of the conductive feedthroughs. A method of imaging an object in a liquid medium and a method of sensing a target species with the liquid cell are also disclosed.

The invention provides a method of detecting a chemical species with an oscillating cantilevered probe. A cantilevered beam is driven into oscillation with a drive mechanism coupled to the cantilevered beam. A free end of the oscillating cantilevered beam is tapped against a mechanical stop coupled to a base end of the cantilevered beam. An amplitude of the oscillating cantilevered beam is measured with a sense mechanism coupled to the cantilevered beam. A treated portion of the cantilevered beam is exposed to the chemical species, wherein the cantilevered beam bends when exposed to the chemical species. A second amplitude of the oscillating cantilevered beam is measured, and the chemical species is determined based on the measured amplitudes.