智慧型手機等可攜式產品在近年來蓬勃的發展，這為可應用於可攜式產品的元件，提供了廣大的商機。超音波馬達由於結構適於微型化、低噪音以及在小型化時的效率較其他致動器為高，因此極適合應用於可攜式產品。
本研究利用雙壓電晶片振動子結構設計超音波馬達，經由適當的電極及結構設計，使之具備二個自由度的運動方向。分別對基本單層型以及積層式壓電振動子超音波馬達進行了性能量測後，在400V/mm電場強度下，基本單層型雙壓電晶片超音波馬達振動子之驅動電壓為120V，最大推力3.0765N，最大速度87.75mm/s，最大效率為4.201%。而積層式雙壓電晶片超音波馬達振動子的驅動電壓則為24V，最大推力2.5782N，最大速度74.23mm/s，最大效率為11.633%。結果顯示積層式振動子有潛力應用於可攜式產品。

The portable devices like smart phone had been developed vigorously in these years. It provides a huge opportunity for those components which can be applied for portable devices. Due to its compact size, low noise and high efficiency in miniature structure, ultrasonic motor shows its advantage for portable devices application.
An ultrasonic motor using bimorph piezoelectric actuator had been developed in this research. There are two degree-of –freedoms movement can be operated through suitable electrode and structure design. The performance had been measured for single layer bimorph actuator and multi-layer bimorph actuator, respectively. Under 400V/mm electric field, the single layer bimorph actuator drove at 120V, maximum trust 3.0765N, maximum free velocity 87.75mm/s and maximum efficiency 4.201%. At the same electric field condition, the multi-layer bimorph actuator drove at 24V and showed maximum trust 2.5782N, maximum free velocity 74.23mm/s and maximum efficiency 11.633%. The result showed the potential of multi-layer bimorph type ultrasonic motor which can be applied for portable devices.

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