利用氧化鋅奈米柱提升表面聲波液體與流體感測器之靈敏度

本研究主要探討使用氧化鋅奈米柱應用於拉福波液體與流體感測器上。聲波感測器(Acoustic Wave Sensor)主要應用在氣體與液體感測器上，而本研究使用拉福波(Love Waves)，做為液體與流體的感測。此實驗先將石英表面聲波元件利用RF Sputter鍍厚度約為1μm、2μm與2.8μm的氧化鋅層，再以水熱法在石英元件上成長出氧化鋅奈米柱，以探討在不同成長時間，氧化鋅奈米柱表面形態對表面聲波感測器特性之影響。液體感測器之靈敏度測定是使用DI Water作為量測，拉福波感測器的靈敏度與導電率，在不同成長時間下的氧化鋅奈米柱，藉由網路分析儀(Network Analyzer)量測S21頻率響應下之相位(Phase)改變及插入損失(Insertion Loss)之增加，可以知道氧化鋅奈米柱成長在拉福波液體感測器上的靈敏度的變化。流體感測器則是將液體感測器做封裝，使用蠕動幫浦將DI Water以流體的方式注入到密封之元件，再由元件預留的另一個孔洞流出，再利用網路分析儀S11頻率響應下的回饋損耗(return loss)變化來量測DI Water不同流速的影響。

關鍵字

石英；拉福波；氧化鋅；奈米柱；液體感測器；流體感測器

並列摘要

The aim of this research is to study the application of ZnO nanorods in Love wave liquid sensor and flow sensor. The main application of surface acoustic wave sensor is to be a gas sensor and a liquid sensor. The theory of this research is to adopt love waves to detect fluid properties. Initially, the quartz surface acoustic waves devices are sputtered with a ZnO thin film that is 1μm、2μm and 2.8μm thickness respectively by RF Magnetron Sputtering system, and then the hydrothermal synthesis approach is employed to grow ZnO nanorods on quartz devices. The different reaction time can influence the growth of ZnO nanorods structure on surface acoustic wave sensor. In measurement, the sensitivity and conductivity of liquid sensor utilizes DI water. In addition, the properties in sensitivity and conductivity of love wave sensor can generate variation under different length of ZnO nanorods. By adopting the Network Analyzer to measure the phase change of S21 frequency response and the increase of insertion loss, the change in sensitivity of love wave sensor distributing ZnO nanorods can be known. In the flow sensor, it is the package of liquid sensor. The different length of ZnO nanorods can also influence the performance of flow sensor. In experiment, in order to probe into the influence of different flow rate of DI water on flow sensor, DI water is pumped into the package device by tubing pump. Ultimately, through the outflow of DI water, the return loss change of S11 frequency response can be measured by using the Network Analyzer.

並列關鍵字

quartz ； Love wave ； ZnO ； Nanorod ； Liquid sensor ； flow sensor

參考文獻

[1]. Z. Wang, J. D. N. Cheeke and C. K. Jen , “Sensitivity analysis for Love mode acoustic gravimetric sensors”, Appl. Phys. Lett. 64 (20), 2940-2942 (1994).

Google Scholar

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