隨著通訊產業的蓬勃發展，表面聲波元件在通訊產業應用最為顯著，因表面聲波濾波器具有體積小、重量輕、低成本、製程與IC技術相容性高及高性能濾波功能等優點，並且可以針對各項需求選用不同的壓電材料，製成適用不同波段的濾波器，是目前無線通訊系統和手機的關鍵零組件。除了在訊號處理方面表現突出之外，近十年來，表面聲波元件以其高質量靈敏度的優異特性，更進一步應用於生物感測領域，表面聲波元件可感測質量、密度、濕度、濃度、氣體辨識或黏滯度等。基本上表面聲波元件運用於訊號處理和生化感測方面的設計是不同的，但所有元件皆運用相同的物理特性及原理。
本論文即以AZ 6112及稀釋後的SU-8作為波導層，利用其低成本和低密度的優點製作出拉福波生物感測器，改善二氧化矽在製程上繁雜，多一道微影與蝕刻程序，而且耗時及費用昂貴等缺點。在元件完成之後，將其應用於去離子水與老鼠細胞(3T3)濃度的感測。由實驗結果發現AZ 6112(波導層厚度2.130 um)比SU-8(波導層厚度1.775 um)更適合作為拉福波元件的波導層，並且其頻率和相位的偏移量皆比SU-8大。除此之外，兩者皆隨著老鼠細胞濃度增加，其頻率偏移量愈大，當滴下相同體積(5 ul)且濃度為6000個數/l的老鼠細胞時，SU-8作為波導層時，其頻率偏移量為18.16 kHz，而AZ 6112作為波導層時，其頻率偏移量237.523 kHz，這表示以AZ 6112作為波導層之元件，其頻率偏移量是以SU-8為波導層的13倍之多，亦即表示以AZ 6112的拉福波元件更適合應用於生物感測。

With the rapid development of communication industry, SAW devices are noticeable in communication application because SAW filters have advantages of small volume, lightness, low costs, high IC-compatibility, and better filtering performance. Different piezoelectric materials can be selected to fabricate various filters with dissimilar wave band, and these SAW filters have become key components of wireless communication and mobile phone. Except for satisfactory signal processing application, SAW devices, which have excellent characteristic of high mass sensitivity, have been further applied to bio-sensing areas in the recent decade. SAW devices can be used to sense mass, density, humidity, concentration, vapor recognition, viscosity, and so forth. Although SAW devices for signal processing and biosensor have different design rule, these devices will use the same physical properties and principles.
In this study, Love wave biosensors using diluted SU-8 and AZ 6112 as guiding layer are fabricated because of their advantages of low cost and low density. They can improve the shortcomings using silicon dioxide as a material of guiding layer, including complex fabrication process, a lot of time spent, and high cost. After finishing the fabrication of Love wave biosensors, D. I. water and mouse cells (3T3) are applied to test these SAW devices. The results show that Love wave biosensor using AZ 6112 (thickness 2.130 m) is better than the one using SU-8 (thickness 1.775 m), which implies that Love wave biosensor using AZ 6112 has better performances of frequency shift and phase shift. With concentration of mouse cell increased, the frequency shifts of these two SAW devices are also increased. Moreover, when the same volume (5 ul) and concentration (6000 piece/ul) of mouse cells are applied to them, frequency shifts of Love wave biosensor using diluted SU-8 and AZ 6112 as guiding layers are 18.16 kHz and 237.523 kHz respectively, which has demonstrated the sensitivity of frequency shift of the latter is thirteen times than the former.

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