Nanodiamond-coated silicon cantilever array for chemical sensing

Diamond offers attractive properties as a material for microelectromechanical chemical sensors but is difficult to process in comparison with silicon. Here a method for attaching detonation-derived nanodiamonds to prefabricated and mounted Si cantilever devices is described. It is shown that this hybrid device has a resonant frequency shifted down, compared to Si alone, by around 10% due to a higher spring constant. Exposure to 2,4-dinitrotoluene leads to an easily observed decrease in resonant frequency. The mechanisms behind these observations are discussed and the promise for this form of hybrid cantilever structure for chemical sensors applications highlighted.