<title>Thin metal film thermal microsensors</title>

Abstract

Design, fabrication, and testing of thermal micro-sensors suitable for miniature and microscopic systems, for application on thin films (free standing or on substrates) as temperature sensors are presented in this paper. The sensors utilize the electrical resistivity temperature dependence of a metal. Using micro-lithography methods, several sets of gold resistors were fabricated in the form of flat 30 to 250 nm thick wires, 7 - 10 micrometers wide, and several cm long in a serpentine shape covering approximately 1.0 mm². These sensors have demonstrated better than 0.001 degree(s) C sensitivity. The electrical resistivity and its thermal coefficient of a thin gold metal film were compared with those of bulk material. Temperature measurements on Si wafers were performed in situations corresponding to x-ray lithography exposure conditions suitable for micromachining. The temperature rise and relaxation time of a silicon wafer during x-ray exposure were measured in vacuum and different He gas pressures.