Wireless surface acoustic wave and MEMS-based microsensors

Abstract

The integration of surface acoustic waves (SAW), microelectromechanical systems (MEMS), and required microelectronics and conformal antennas to realize programmable microsensors suitable for many engineering and biomedical applications will be reviewed in this talk. This unique combination of technologies results in novel conformal sensors that can be remotely sensed by a wireless communication system with the advantage of no power requirements at the sensor site (passive sensor). The required features in many of these applications are high precision, wide dynamic range, and wide frequency range. The MEMS-SAW-based devices presented possess typical advantages of MEMS sensors including the additional benefits of robustness, excellent sensitivity, surface conformability, and durability. After a brief overview of SAW sensors and MEMS, the paper is focused on the design and fabrication of MEMS devices for engineering and medical applications, for example: accelerometer and gyroscopes for automobile, inertial navigation; sensors for pressure, torque, temperature, and strain; health monitoring of structures; ‘‘smart tongue and electronic nose;’’ micropump for drug delivery; humidity, temperature, and ethlyne oxide sensor for hospital sterilization system; microsensors for monitoring bone healing; and pollution and chemical sensing.