气凝胶填充式微热板的设计及性能测试

Design and performance test of aerogel⁃filled micro hot⁃plate

为改善封闭膜式MEMS硅基微热板的热耗散问题,设计并制备了加热区域为200μm×200μm气凝胶填充式微热板结构,气凝胶填充采用刮涂工艺实现。背腔中填充的二氧化硅(SiO_(2))气凝胶可减小封闭膜微热板背腔引起的热损失,同时提升加热区域的温度分布均匀性。测试结果表明:刮涂工艺可以满足圆片级微热板进行气凝胶填充;微热板工作温度越高,气凝胶填充式结构对封闭膜微热板的热损失问题改善效果越明显;工作电压为4 V时,升温到590℃,功耗为50.04 mW,加热效率提高了12%,热响应稳定性更好。在烟尘传感器上进行性能测试,测试结果表明:可满足烟尘传感器吸附区对烟尘颗粒氧化解吸的需求。

In order to improve heat dissipation of the closed⁃membrane MEMS silicon⁃based micro hotplate,an aerogel⁃filled micro hotplate structure with heating area of 200μm×200μm is designed and fabricated,and aerogel filling is realized by scraping process.The SiO_(2)aerogel filled in the back cavity can re⁃duce the heat loss caused by the back cavity of the closed film micro hotplate,and at the same time improve the uniformity of temperature distribution in the heating area.The test results show that the scrape coating process can meet the aerogel filling of the wafer⁃level micro hotplate;the higher the operating temperature of the micro hotplate,the more obvious the improvement effect of the aerogel⁃filled structure on the heat loss problem of the closed⁃film micro hotplate.When the working voltage is 4 V,the temperature rises to 590℃,the power consumption is 50.04 mW,the heating ef⁃ficiency is increased by 12%,and the thermal response stability is better.The performance test is carried out on the soot sensor,and the test result shows that it can meet the demand for the oxidation and desorption of soot particles in the adsorption area of the soot sensor.