A Novel RFID-Based Thermal Convection Type Inclinometer with Nonfloating Structure and Xenon Gas

Abstract

This research proposes a novel wireless RFID-based thermal convection inclinometer. Six new ideas are presented. The first one is to make it on a flexible substrate to reduce the energy dissipation through the traditional silicon. The second one is to integrate both an inclinometer and a wireless RFID antenna on the same substrate, such that it becomes a wireless sensor and very convenient for usage. The third idea is to apply a hemi-cylindrical chamber instead of the previous rectangular one, so the gas distribution is more streamlined to increase the sensitivity. The fourth idea is to apply xenon gas instead of the traditional carbon dioxide; the latter may oxidize the heater and the thermal sensors. The fifth idea is to use a nonfloating structure instead of the floating one, thus it is more simple and low cost without making a cavity in the substrate. The sixth idea is to apply a stacking material for the temperature sensors, so that the sensitivities are better. Three kinds of stacking height were studied, such as 1, 1.5 and 2mm. Moreover, three types of material with different thermal conductivity are also tested, such as alumina nitride (AlN), copper and silicon. One can see the combination of AlN/2mm is better, and the sensitivity curve is approximate to a theoretical sinusoidal one.