A FIBER OPTICAL VOLTAGE SENSOR PREPARED BY MICROMACHINING AND WAFER BONDING

A fiber optical sensor in silicon is demonstrated with an optical cavi ty prepared by a micromachining and silicon wafer-bonding technique fo r measuring voltages superimposed on high electric potentials. It cons ists of an n-type and a p-type silicon wafer bonded together, surround ing a cavity with controlled depth. One of the wafers is etched to for m a thin membrane which can be bent by an applied voltage, thus changi ng the depth of the cavity and the interference properties of light pe netrating the structure.