表面横波生物传感器的灵敏度分析

分析了延迟线型表面横波(STW)生物传感器的灵敏度与栅阵材料、厚度的关系。给出了计算栅阵对表面横波束缚能力的方法,由STW的束缚能力可以直接得到传感器的灵敏度。从Auld微扰理论出发推导出表面横波传感器灵敏度的表达式。根据上述理论分析,以AT切割压电石英基片为例,分别计算金、银、铝三种栅阵材料在不同厚度时的传感器灵敏度,并给出对比分析结果。结果表明,在相同栅阵厚度时,采用金栅阵的传感器灵敏度最高,银次之,铝最小;传感器的灵敏度随着栅阵厚度的增加而增加。

Sensitivity Analysis of Surface Transverse Wave Biosensor

The mass sensitivity of the surface transverse wave(STW) biosensor effected by the material and thickness of the grating was analyzed.A method was given to analyze trapping strength of the grating to STW because trapping energy was relative to sensor sensitivity directly.Then, based on the Auld perturbation theory,the formulas were deduced to calculate the biosensor mass sensitivity.An example was present by this method when the substrate and electrode metal were adopted the AT-cut piezoelectric quartz and gold、silver or aluminum respectively.When the relative thickness of electrode is given,the gold grating achieves the highest sensitivity,while the silver grating takes the second place and aluminum grating is least.As for the same metal,the biosensor sensitivity increases as the grating height increases.