隨著半導體技術的不斷進步，大尺寸相控陣和驅動電路的成本變得更加便宜，同
時體積也變得更小。因此，這種技術進步為空氣耦合超聲波傳感器陣列在多個領域展
示了應用前景，例如:超聲觸覺反饋、聲懸浮等等。然而，傳統的空氣耦合超聲波傳感
器目前體積過於龐大，這限制了這些應用的商業化發展。因此，為了克服這一挑戰，
本研採用壓電式微機電超聲換能器（pMUT）作為傳統超聲換能器的替代方案。其中，
PZT 薄膜成為了 pMUT 最具潛力的壓電材料之一，然而現有的 PZT 製造方法成本高
昂，或需要使用稀有金屬材料。為了解決這個問題，本研究提出了一種經濟高效且可
靠的 PZT 薄膜製造方法。該方法採用商用 PZT 溶膠-凝膠溶液作為種子層，隨後通過
射頻濺射技術成功地沉積了高壓電性能之 PZT 薄膜，其剩餘極化強度達到 113.35
μC/cm²，矯頑力場達 211.6 kV/cm。利用這種製造方法，成功地製備出 pMUT 和 pMUT陣列。並且本研究透過有限元素分析法進行模擬，對 40kHz 的 pMUT 進行了結構參數優化，然後使用標準麥克風進行聲壓測量，以評估 pMUT 和 pMUT 陣列的性能。
新方法所製造的 pMUT，位於其上方 3cm 處，能夠產生 0.764 Pa/V 的聲壓，並在
52.2kHz 的諧振頻率下運作。而對於 pMUT 陣列，在陣列中心上方 3cm 處，最大聲壓
達到 87.4 Pa。這一聲壓表現不僅超越了已知 100kHz 頻段空氣耦合 pMUT 陣列的最
高聲輸出壓力，更凸顯出將這種新的 PZT 薄膜製造方法應用於高壓半空超聲應用（例
如超聲觸覺反饋和聲懸浮）的巨大潛力。

Due to the development of semiconductor technology, control and driving circuits for large-size phased arrays have been cheaper and tidier. Therefore, several applications of aircoupled ultrasonic transducer arrays were published, such as ultrasonic haptic feedback and acoustic levitation. However, current aircoupled ultrasonic transducers were bulky. It prevented the commercialization of these applications. Hence, the piezoelectric micromachining ultrasonic transducer (pMUT) was proposed to replace conventional ultrasound transducers. Currently, PZT thin film is the most convincing piezoelectric layer for pMUT. Nevertheless, the existing PZT fabrication methods were too expensive or required rare metal material. Therefore, this study proposed a cost-effective and reliable PZT
thin film fabrication method. Through depositing a commercial sol-gel solution as a seed layer followed by the radio frequency sputtering, a PZT thin film with remnant polarization of 113.35 (μC/cm2 ) and coercive field of 211.6 (kV/cm) was demonstrated. Besides, pMUTs and pMUT arrays were made based on the PZT thin film. Moreover, the FEM simulations were conducted to optimize the structure parameters for 40 kHz pMUT. The standard microphone was used to measure the acoustic pressure to evaluate the performance of the pMUT and pMUT array. The pMUT made by the proposed thin film deposition method could generate 0.764 Pa/V at 3 cm above it with a resonance frequency of 52.2 kHz. As for the pMUT array, the maximum acoustic pressure of 87.4 Pa was measured at 3 cm above the
center of the array. It was the highest known acoustic output pressure in published sub-100 kHz air-coupled pMUT arrays, highlighting the promising potential of using the proposed PZT thin film deposition method for high-pressure midair ultrasonic applications such as ultrasonic haptic feedback and acoustic levitation

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