Patent ID: 10241129

Abstract:
A novel high resolution, low noise MEMS capacitive accelerometer is disclosed. The accelerometer utilizes a piston-tube electrode configuration that enables the use of a wide area for the electrodes. Therefore, a high capacitive sensitivity is achieved. The accelerometer consists of two structures: upper and lower. The lower structure contains a plurality of fixed electrodes that are attached to the base and have a piston-style shape (teeth). Those pistons form the sensing electrodes of the accelerometer. The upper structure contains a plurality of moving electrodes that have a tube-style shape (through holes), and they are attached to a substrate via restoring mechanical springs. The proof mass of the accelerometer is distributed around these tubes to reduce squeeze thin film damping in the system. The accelerometer is able to sense linear acceleration along the z-axis and/or the angular acceleration about the in-plane axes (x and y).