Thin film resistance thermometer with simple package for cryogenic application

Abstract

In this paper, we proposed a novel simple package based on micro-machining for thin-film cryogenic temperature sensors. The substrate with temperature sensitive element fabricated by micro-machining process, directly used as the package substrate. Then, the silicon cover soldered on the substrate, providing vacuum encapsulation with high air tightness. Subsequently, we researched the reliability of the package by leak rate detection, shear force test and scanning electron microscope. Lastly, the temperature response curves, measurement fluctuation, thermal response time and short-term stability of the thermometers had been researched. Compared to the traditional package, the simple package simplified manufacturing process, reduced cost. Furthermore, the temperature sensitive element directly deposited on the package substrate, reduced sensor mass and improved thermal response speed.