基于声表面波技术探测微量气体的理论分析

Theoretical analysis of detecting micro-gas based on surface acoustic wave

声表面波延迟线振荡器的频率对沉积在延迟线表面上的薄膜很敏感,在延迟线路径上覆盖一层具有选择性的吸附薄膜,这层薄膜吸附对其敏感的气体物质后,其质量密度、弹性参数、介电常数、电导率都将发生变化。给出了传感器的理论分析,根据检测需要,设计最优化的气体传感器。

The frequency of the delay line oscillator of surface acoustic wave is very sensitive to the film deposited on surface of the delay line. The mass density, elastic constant, dielectric constant, conductivity of these films will change after absorbing these sensitive gases. The theoretical analysiss of the sensor is presented. The optimization of gas sensors is designed based on the need of detection.