聲波噴墨法不同於熱氣泡式和壓電致動式，可改善噴墨阻塞、墨滴方向性與衛星點等問題，為一新興噴墨列印技術，藉由供應高頻弦波電能於壓電換能器使其產生超音波，平面波通過聚焦透鏡後匯聚成超音波束，推動液面墨水而達到噴墨效果。 本研究主要分為聚焦透鏡與壓電換能器兩部份，聚焦透鏡依據超音波噴墨相關理論設計 100 MHz 及 200 MHz 之微尺寸聚焦透鏡，規劃微機電製程，成功製作出四階層結構；選用鋯鈦酸鉛作為壓電換能器，自行調配溶膠凝膠溶液後，以旋鍍法製作不同厚度之試片，X 光繞射儀觀察壓電膜隨厚度增加其晶格結構越佳，藉由電容與電壓關係驗證鋯鈦酸鉛具備壓電效應，並且利用阻抗分析儀確認換能器之共振頻率，目前已經成功製作出共振頻率為 800 MHz、820 MHz 和 1.05 GHz 之 PZT 壓電換能器。實驗已個別驗證微尺寸聚焦透鏡與壓電換能器之製作與特性，並累積相關微機電製程上經驗，以利未來噴墨頭改良。 Ultrasonic inkjet method is different from the thermal bubble and piezoelectric actuating methods; it is a new inkjet printing technology. This method can improve some drawbacks arising from thermal-bubble and piezoelectric actuating printing such as, blocked printing head, droplet-directionality and satellite problems. The piezoelectric transducer can generate ultrasound through supplying high-frequency sinusoid voltage. After the plane wave translates through the focusing lens, focused ultrasonic energy on the ink surface is able to inkjet. This research is mainly divided into the focusing lens and piezoelectric transducer. According to the ultrasonic inkjet theory, the micro focusing lens is designed 100 and 200 MHz. The MEMS process is planned, and the focusing lens which is four steps structure is successfully fabricated. PZT is a material which is used for the piezoelectric transducer. After producing the sol-gel solution, the samples of different thickness PZT films are made by spin-coater. The crystalline grain structure is observed by the XRD instrument, the structure of thicker film is better. The piezoelectric effect of PZT is proved by the capacity and voltage relation, and the resonance frequency of the piezoelectric transducer is confirmed by the impedance analysis instrument. The PZT piezoelectric transducer which resonance frequency are 800 MHz, 820 MHz and 1.05 GHz have already been manufacture. This study has completed the fabrication and verified the characteristics of the focusing lens and piezoelectric transducer, respectively. The obtained MEMS design and fabrication experiences are helpful to the improvement of printing head study in the future.
