Carbon-metal vibrating nanomembranes for high frequency microresonators

International audienceA new process to reproducibly manufacture high frequency microresonators based on few nanometer thick Ni/a-C/Pt nanomembranes is presented. An MM in tapping mode is then used to characterize the devices under electrostatic actuation, which allows the detection of the resonance frequencies and a spatial mapping of the resonant modes. Depending on their width, the 0.8 to 2.3 mu m wide resonators show resonance frequencies ranging from 20 to 110 MHz for a quality factor ranging from 14 to 291. The dependence of the resonance frequency on the resonator width are discussed considering a continuum mechanic model. A membrane-like behavior appears to mainly rule the mechanical behavior of the resonators. Together with the particular device geometry, these mechanical properties lead to remarkable effects when the resonators are driven under a large electrostatic power. In particular, a mean vibration amplitude up to 150 nm was observed and 2D vibrational modes were activated, which paves the way to the development of new applications in various fields such as medical imaging and chemical sensing