We report the implementation of a passive temperature compensation technique in thermally actuated, silicon-based, resonant cantilever gas sensors vibrating in their fundamental in-plane resonant mode. The temperature compensation technique utilizes oxide-filled trenches along the edges of the cantilever structure and adds a single additional mask to the overall fabrication process. The trench width for effective temperature compensation was optimized using finite element simulation. The fabricated resonators exhibit a temperature coefficient of frequency (TCF) as low as 1.7 ppm/°C, which represents a 15x improvement compared to the same resonators without oxide trenches. Quality factors of devices with oxide compensation are similar to those measured in non-compensated counterparts. The temperature compensation technique addresses a key limitation of silicon-based, mass-sensitive chemical microsensors, namely their temperature instability due to inherent temperature-dependent material properties. Compared to our previous work, the improved frequency and baseline stability yields an almost order-of-magnitude improvement in the extrapolated limit of detection, approaching 100 ppb for toluene. [2020-0154]

中文翻译：

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使用嵌入式氧化物填充沟槽的热驱动平面谐振气体传感器的温度补偿

我们报告了被动温度补偿技术在热驱动、硅基谐振悬臂式气体传感器中的实现，该传感器以其基本的面内谐振模式振动。温度补偿技术利用沿悬臂结构边缘的氧化物填充沟槽，并在整个制造过程中增加了一个额外的掩模。使用有限元模拟优化了有效温度补偿的沟槽宽度。制造的谐振器的频率温度系数 (TCF) 低至 1.7 ppm/°C，与没有氧化物沟槽的相同谐振器相比，性能提高了 15 倍。具有氧化物补偿的器件的质量因子与未补偿器件的测量值相似。温度补偿技术解决了基于硅的质量敏感化学微传感器的一个关键限制，即由于固有的温度相关材料特性而导致的温度不稳定性。与我们之前的工作相比，改进的频率和基线稳定性使外推检测限提高了几乎一个数量级，甲苯接近 100 ppb。[2020-0154]