摘要

A ceramic hotplate with the structure of suspending bridge was designed to improve the thermal stability of silicon micro hotplates. The heat transfer process of the hotplate was analyzed and the characteristics of steady-state thermal response and the electrode structure of a heater were simulated by using the finite element method. Combined the conventional microelectronic technology and laser micro processing technology, the microstructures with thickness of 100 μm and bridge width of 2 mm were produced actually and the property of power assumption verses the temperature was measured. The results show that the hotplate has good stability at high temperature, and the average temperature on the ceramic hot-plate can reach 630°C when a 1.5 W heating power is applied. By taking the ceramic hotplate as heating platform and nano-scale SnO2 materials with Pd doping concentration of 0.2% and 10% (atom number percentage) as sensitive membrane materials, respectively, the array with two sensors was designed and fabricated. Experiments show that when the sensor array works in the constant voltage heating mode, it can be used as a single sensor with good response to CO or CH4 gases. When the sensor array works at pulse voltage heating mode with alternating high or low working temperatures, it can realize quantitative detection for mixed gases of CO and CH4.

  • 出版日期2012

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