Thermomechanical behavior of a bimaterial microchannel cantilever subjected to periodic IR radiation

Here we report the thermomechanical response of a bimaterial microchannel cantilever (BMC) subjected to periodic heating by IR radiation. A detailed theoretical and experimental study was performed considering the BMC as a thermal sensor. Experiments were conducted to find out the thermal sensitivity and power sensitivity of various BMC designs. The thermal sensitivity of the BMC was found by monitoring the response of the BMC to external heating while the power sensitivity was measured by observing its behavior to varying incident IR power. We report a minimum measurement of 60 μW of power, an energy resolution of ∼ 240 nJ and a temperature resolution of 4 mK using the BMC. The optimum BMC design was chosen to demonstrate a spectroscopy application to detect a minimum of 1.15 ng of ethanol in ethanol-water binary mixture. The purpose of this paper is to add molecular selectivity to the ultra-sensitive, novel design of microchannel cantilevers using photothermal spectroscopy techniques for biosensing applications.