Nanofabrication, effects and sensors based on micro-electro-mechanical systems technology

In this paper, our investigation of nanofabrication, effects and sensors based on the traditional micro-electro-mechanical systems (MEMS) technology has been reviewed. Thanks to high selectivity in anisotropic etching and sacrificial layer processes, nanostructures such as nanobeams and nanowires have been fabricated in top-down batch process, in which beams with thickness of only 20 nm and nanowires whose width and thickness is only 20 nm were achieved. With the help of MEMS chip, the scale effect of Young's modulus in silicon has been studied and confirmed directly in a tensile experiment using electron microscopy. Because of their high surface-to-volume ratio and small size, silicon nanowire (SiNW)-based field-effect transistors (FETs) have been shown as one of the most promising electronic devices and ultrasensitive detectors in biological applications. We demonstrated that an SiNW-FET sensor can reveal ultrahigh sensitivity for rapid and reliable detection of 0.1 fM of target DNA with high specificity. All these indicate that the MEMS technology can pave the way to nanoapplications with its advantages of batch production, low cost and high performance.