Applications of Microsystems in precision measurements

Abstract

Summary form only given. Micro electro mechanical system (MEMS) is a new potential technology to fabricate DC and AC voltage references, AC/DC converters, and high frequency power sensors. In addition, MEMS is very suitable technology for stable reference oscillators. The stability of the components is based on single crystal silicon springs, stress free substrate material (SOI) and metallized surfaces on both capacitor surfaces defining the geometry. The system is either vacuum encapsulated or in protective atmosphere depending on the application. AC and DC voltage references are based on the pull-in voltage, which characterizes a moving plate capacitive MEMS component. An AC/DC converter and a high frequency power sensor utilizes a seesaw structure, which is kept in balance by force feedback. The force is directly proportional to the RMS value of the AC and DC signals. We have also studied the work functions of different metals on silicon to improve the sensor long-term stability. In this paper our new silicon on insulator (SOI) manufacturing process, specially developed for electrical references, will be described. In addition, our recent results will be discussed. The stability and resolution of these new references are compared to existing components such as Zener diodes, thermocouples and rf diodes