DESIGN AND OPTIMIZATION OF PLATINIUM HEATERS FOR GAS SENSOR APPLICATIONS

A new bridge-type micro-hotplates (MHP) for semi-conducting metal oxide (SMO) gas sensor is investigated and its numerical study is simulated using Finite Element Method. the boundary conditions of the thermal properties have been calculated. The proposed MHP has been designed for low power consumption and uniform temperature distribution throughout the active area of 240 µm × 240 µm. To validate our simulation, we compared the results with the experimental data, reported by Iwata et al. The power consumption of the heater is approximately corresponded to 13.5 mW for heating to 300°C (heat transfer coefficients calculated), we noticed a reduction of power consumption by more than 8 mW compared to our first simulation (standard heat transfer coefficient parameters) which proves the impact of heat transfer coefficients on power consumption. Also, overheating problem in the heater center is analyzed, several modifications on the MHP center design have been established to keep the best temperature homogeneity, results show that temperature gap between extremities and the center of the active area is reduced by less than 15 °C.