Graphene-based stand-alone nanomechanical membrane production and mass-acoustic hybrid-sensor application

Abstract

In this article, experimental studies were carried out for the preparation, characterization, and nanomechanical membrane application of Graphene-based nanomechanical mass and acoustic hybrid sensors. The purpose of this study was to prepare facile and low-cost nanomechanical membrane-based mass-acoustic hybrid sensors by set-ups developed on the exfoliation and membrane transfer methods, and to examine their morphological, spectroscopical, and nanomechanical-vibrational properties, as well as the membrane characteristics like mass and acoustic sensitivities and durability over time. For the experiments, equipment and items such as optical, digital, atomic force and scanning electron microscopes, Raman spectroscope, acoustic signal source and amplifier, data-logger, sound pressure level meter, and laser Doppler vibrometer were used. Graphene-based nanomechanical membrane sensor chips with varying acoustic pressure levels and mass-loadings were tested. It was observed that the acoustic sensitivity of the produced 706.5 µm2 nanomechanical membranes increased with increasing sound pressure levels and decreased with increasing mass-loads. With 67.8 ± 5 nm/Pa, the unloaded nanomechanical membrane was the most sensitive sample. Experimental challenges and sensor development solutions were discussed. Existing application examples were examined and discussions were made on the current challenges and the future prospects of the nanomechanical membrane sensors.