Characteristics of a Membrane Temperature Sensor with Variations of Silicon Oxide Thickness

In this study, to improve the performance of a temperature sensor, a thin oxide film was deposited on the silicon substrate in addition to controlling the substrate thickness of the sensor. We investigated the effect of the oxide film on the sensitivity and reaction time of the sensor by preventing the heat conduction to the lower silicon substrate. The deposition characteristics of the oxide films were observed at 900 ◦ C, and either 1 Torr or 10 torr in the furnace using the dry oxidation method. The reaction time of the temperature sensor was calculated using the heat diffusion rule Fick's second law. The sensitivity was determined by measuring the temperature variation according to the applied power; the heat response time was about 5 times faster and the sensitivity was improved about 2 times compared with the bulk silicon substrate.