本論文主要以射頻磁控濺鍍法，研究在石英(42°45 ST-cut Quartz)與鉭酸鋰(36°YX LiTaO3)基板上成長軸C軸（002）軸向的氧化鋅(ZnO)薄膜。文獻中顯示，在石英基板上成長（002）軸向的氧化鋅薄膜較為常見，但鮮少在鉭酸鋰基板上成長（002）軸向的氧化鋅薄膜，多半為（110）軸向，所以我們設計不同的製程參數：控制氬氣與氧氣的比例、腔體內壓力、濺鍍功率、濺鍍時間、靶材成分、改變基板溫度及退火處理溫度，分別在兩種基板上成長出具有（002）軸向的氧化鋅薄膜，利用X光繞射儀(XRD)、掃描式電子顯微鏡(SEM)、原子力顯微鏡(AFM)檢測薄膜晶體的結構、內應力、與薄膜表面粗糙度。
　　將此薄膜應用於以42°45 ST-cut Quartz、36° YX LiTaO3為基板的拉福波(Love wave)感測器上，成長不同鋰、鎂掺雜量之氧化鋅薄膜，研究不同參雜量的電阻率和靈敏度，在鋰1.5 mol％、鎂1 mol％，有最大電阻率，相較於只有掺雜鋰1.5 mol％所成長的氧化鋅薄膜，電阻率約提升了100倍，且得到較佳之靈敏度。在此兩種基板上，成長不同厚度的氧化鋅薄膜，研究不同膜厚對元件頻率響應、機電耦合係數、靈敏度和溫度頻率係數的影響：在石英基板上，厚度與波長比值t/λ＝0.033（膜厚1.35μm，中心頻率111.9MHz，波長40μm）時，靈敏度最大，而當薄膜成長五小時，其溫度頻率係數近乎為0；在鉭酸鋰基板上，當厚度與波長比值t/λ＝0.058（膜厚2.31μm，中心頻率99.4MHz，波長40μm）時，顯示其靈敏度最大。另外，在不同基板溫度下，成長氧化鋅薄膜於此兩種基板上，研究不同基板溫度對元件頻率響應、表面粗糙度及靈敏度的影響：在石英基板上，基板不加溫時，有最小表面粗糙度2.273nm，最大靈敏度-8.71× 10-8 m2 s kg-1；在鉭酸鋰基板上，基板不加溫時，最小表面粗糙度6.007nm，最大靈敏度為-5.30× 10-8 m2 s kg-1；可知在相同條件下，以石英為基板的拉福波感測器比以鉭酸鋰為基板的拉福波感測器有更好的靈敏度。

　　Poly-crystal ZnO films with c-axis (002) orientation have been successfully grown on the ST-cut quartz substrate by RF magnetron sputtering technique. It has been rarely reported to deposit c-axis (002) orientation ZnO film on the 36° YX-LiTaO3 substrate. So far, most ZnO films on 36° YX-LiTaO3 substrate are obtained (110) orientation. We try to deposit c-axis (002) orientation ZnO film on the 42°45 ST-cut quartz and 36° YX-LiTaO3. The deposited films were characterized as a function of argon-oxygen gas flow ratio, RF power, chamber pressure, target component, substrate temperature, and annealing temperature. Crystalline structures, stress and surface roughness characteristics of the films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM) measurement.
　　We grow the films on the substrate (ZnO/IDT/quartz, ZnO/IDT/LiTaO3) as a Love wave sensor. With the different doping ratio of Li and Mg, the resistivity and sensitivity are measured. The resistivity of Li 1.5 mol% and Mg 1 mol% doped ZnO films is increased with two orders to only Li 1.5 mol% doped. The sensitivity is also larger than that of Li 1.5 mol% doped. An experimental study of Love wave devices based on ST-cut quartz, YX-LiTaO3 with different thickness of ZnO films is also presented. Frequency response, electromechanical coupling coefficient, sensitivity, and temperature coefficient of frequency have been analyzed as a function of layer thickness. On ZnO/IDT/quartz structure, the maximum sensitivity is obtained for 1.35�m ZnO film with the center frequency of 111.9MHz, and the temperature coefficient of frequency closed to zero is obtained for 2.31　m ZnO film with the center frequency of 99.4MHz for a wavelength of 40�m, respectively. Besides, the Love wave sensor has higher sensitivity for ZnO films sputtered on unheated substrate than on heated substrate. The best sensitivity of the ZnO/IDT/quartz structure is -8.71× 10-8 m2 s kg-1 with the film surface roughness of 2.273nm, which is larger than the best sensitivity of the ZnO/IDT/LiTaO3 structure with the sensitivity -5.30× 10-8 m2 s kg-1 and the roughness 6.007nm. It reveals that under the same conditions, Love wave sensors based on 42°45 ST-cut quartz have higher sensitivity than on the substrate of 36° YX-LiTaO3.

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