High-sensitivity and low-power inertial MEMS-on-CMOS sensors using low-temperature-deposited poly-SiGe film for the IoT era

In this paper, for the first time we demonstrate the material benefits of SiGe for MEMS applications based on the results of fabricated devices. To achieve SiGe inertial MEMS, we develop the deposition process for thick, low-temperature poly-SiGe film with which film stress is controlled precisely, and fabricate SiGe accelerometers having 20µm thickness. We clarify that the SiGe accelerometer shows higher sensor sensitivity and lower power consumption compared to Si one and is thus suitable for future ultra-low-power sensors.