本論文主要研製與分析薄膜體聲波諧振器(thin film bulk acoustic wave resonator, FBAR)及濾波器，分別採用背向蝕刻結構的FBAR元件、階梯式FBAR濾波器，而FBAR的結構為在矽基板上沉積下電極鉑、壓電層氮化鋁、上電極鋁。本研究以反應式射頻磁控濺鍍沉積C軸優選取向的氮化鋁薄膜，以激發縱向聲波、產生壓電效應，最終具備的諧振頻率可以達到濾波的效果。實驗結果探討濺鍍中製程參數對氮化鋁薄膜特性的影響，並透過微結構分析，發現氮氬氣體流量比為7:3 (sccm)、濺鍍功率為300W、工作壓力為 5×10^-3Torr、基板溫度為225℃時，沉積出具有最佳C軸優選取向的氮化鋁薄膜，並作為FBAR元件及濾波器的壓電薄膜。在FBAR製作流程中，發生上電極Al斷裂、蝕刻遮罩無法抵擋ICP蝕刻、光阻殘留等問題，經由檢討實驗的缺失，分別提出增加上電極厚度或使用準直管、使用光阻或金屬薄膜作為蝕刻遮罩、利用RIE乾式蝕刻將氧分子解離以去除光阻等方法，有效地改善製程上遇到的問題，並提高製作良率。最後透過頻率響應分析，探討FBAR元件及濾波器的微波特性，並藉由ADS模擬軟體萃取MBVD等效電路的元件數值。本研究製作出工作頻率為5.170GHz的FBAR元件及5.153GHz的FBAR濾波器，達成中心頻率為5GHz的目標，但其穿透損耗太大，將會是未來改善的目標。

In this thesis, we fabricated and analyzed thin film bulk acoustic resonators (FBARs) and filters. The FBAR consists of a piezoelectric AlN thin film sandwiched between a top electrode of Al and a bottom electrode of Pt. The FABR is connected with input and output ports of GSG transmission lines. The FBAR is made on the surface of SiNx / Si which is attached to an etched cavity in the back of the Si substrate. The piezoelectric layer was formed by using RF magnetron reactive sputter. There were four process parameters to control the crystal structure of the thin film. Thin film with small FWHM and vertical C-axis is preferable. The analysis of XRD, SEM and AFM showed that the parameters of nitrogen and argon gas flow rate of 7:3 (sccm), sputtering power of 300W, operating pressure of 5×10^-3Torr and substrate temperature of 225℃ could produce the best quality of thin film. FBAR elements of 22500μm^2 of area and 0.8 μm of AlN thickness were fabricated and the measured S-paramers indicated the resonant frequency was 5.170GHz, the anti-resonant frequency was 5.190GHz, effective electromechanical coupling coefficient was 0.951% and quality factor was 706.890. The MBVD model was analyzed by using the ADS software and well-fitted values of circuit elements were obtained. A T-type FBAR bandpass filter was successfully fabricated and demonstrated. The measured S-parameters implied the center frequency was 5.153GHz, the bandwidth was 20MHz and the insertion loss was -13.121dB.

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