Self-powered triboelectric MEMS accelerometer

A self-powered triboelectric accelerometer miniaturized to the micro-scale is presented. This micro triboelectric accelerometer (MTEA) was fabricated using CMOS-compatible processes. The design followed the triboelectric nanogenerators made in meso-scale and operates in the contact-separation mode. The scaled-down, multilayer design enabled fabrication using microelectromechanical systems (MEMS) technology. The MTEA was made using an aluminum and polyimide triboelectric pair that generated charges on the contact. A square movable plate that is 2 mm × 2 mm was fabricated with 1 μm thickness. Then, the fabricated MTEA was excited by a mini-shaker at known frequencies (0.1–7 kHz) and accelerations (1–10 g), and the output was recorded. The output was 0.7 V at the resonance frequency (700 Hz). The generated voltage has a linear relationship with the acceleration with a maximum sensitivity of 70 mV/g at the 700 Hz excitation frequency.