Zero-Power Chemical Sensor Based on a Polymer/Metal Micromechanical Switch

This paper reports on the first proof-of-concept experimental demonstration of a zero-power chemical sensor. Differently than any other chemical sensors, the proposed device relies on a chemically actuated micromechanical switch to digitize the chemical concentration in the environment without consuming any electrical power. The switch is implemented with a polymer-metal bimaterial cantilever that deforms when exposed to targeted chemical vapor. It is only triggered when the concentration of targeted chemicals is above a predetermined threshold, otherwise the device remains dormant with zero power consumption. Such a unique feature is expected to enable large area deployment of low-cost, ultra-miniaturized sensors for chemical detection. The first prototype shown here is capable of detecting ethanol vapor with concentration of 2.46% (mixed with dry air).