An integrated ‘smart’ device which combines the functions of a mass threshold value gas sensor and an electro-mechanical (MEMS) switch that actuates an alarm or defensive security
The novel active structure can be engineered into MEMS devices used to sense a variety of biologics, chemicals, explosives, allergens, drugs, pollutants, and, nano-engineered materials. The invention relies on electrostatic actuation of a parallel plate capacitor, Figure 1, in which one plate (or any other structure of arbitrary shape) is stationary and the other plate is movable and is actuated or biased by an electrostatic DC force. The device integrates the functionality of separate components (sensors, actuators, decision units, amplifiers, analog to digital converters) into one package. High reliability is built into the design of the device: the switch will operate only when the concentration of the hazardous gas or material exceeds an encoded threshold value. The device has the ability to deploy in the field and detect in real time without use of lab and is simple and inexpensive to batch-fabricate, calibrate and operate.
• Simple and inexpensive to batch-fabricate, calibrate and operate
• Low-power, low-weight, small foot-print design
• Built-in reliability – the switch operates only when the concentration of the hazardous gas or material exceeds an encoded threshold value
• Speed – ability to deploy in the field and detect in real time without use of lab