A Precision Yaw Rate Sensor in Silicon Micromachining

A new generation of production-ready dual function sensor which combines a yaw rate sensor with a linear accelerometer, based on silicon micromachining, is presented. The sensor is designed for mass production and high performance applications such as vehicle control systems. A combination of surface and bulk micromachining leads to an advantage in design, signal evaluation and packaging. This paper discusses the design of the sensing elements: the yaw rate sensor consists of two bulk micromachined oscillating masses each of which supports a surface micromachined accelerometer for detection of the coriolis force. The sensing element for the linear acceleration is a separate surface micromachined accelerometer. The electrodynamic actuation and high Q-value of the oscillator allow packaging at atmospheric pressure. Characterization results of the device are presented.