微熱致動器為利用材料受熱膨脹之特性，使結構產生形變，根據形變的方向，可分為同平面(in-plane)與出平面(out-of-plane)等兩種致動方向，而因幾何結構與製程之限制，鮮少同時具有兩個形變自由度的微致動器，因此，本文以V型樑為主要結構，設計出可於低溫時產生同平面位移、高溫時則轉變為出平面位移的二維移動軌跡微熱致動器。
本研究以熱為單一驅動力，藉由數值模擬觀察於改變結構樑幾何尺寸後，各方向形變量之變化與趨勢，同時比較與Z型結構樑之差異。由模擬結果歸納出深寬比、傾斜角度兩項主導形變方向的參數，並分析出兩型式結構樑角度之等效關係。於各方面比較後，選擇大深寬比與大角度進行結構圖形設計，並以熱傳導係數較佳之鋁薄膜做為結構之主要材料，同時調整兩種結構樑之排列方式，以克服兩結構於大角度時，耦合樑於出平面方向之水平高低差。
實驗結果顯示，本文主要探討之V型結構樑於幾何調整後，在溫度160℃時，可得到16.8 μm的最大水平位移與57.2 μm的最大垂直位移，並經由適當設計後，將水平高低差由6 μm減少至2 μm；而Z型結構樑可分別於同平面與出平面得到8.5 μm與72.3 μm之最大位移，並於調整排列方式後，將高低差由8 μm減少至3 μm。

Micro-thermal actuators deform the structure by heating the material. According to the direction of deformation, the directions of micro-thermal actuators’ actuation can be divided into two parts, in-plane and out-of-plane. Due to the limitations of structure and manufacturing process, microactuators with two degrees of freedom in deformation are rarely used at the same time. Therefore, we use V-shaped as the main structure of the component, designing a two-dimensional movement trajectory micro-thermal actuator that can produce in-plane displacement at low temperature and out-of-plane displacement at high temperature.
We use heat as a single driving force. Through numerical simulation, the trends of the deformation in each direction after changing the geometric size of the V-shaped structural beam are observed, and compare the difference from the Z-shaped structural beam. Due to the simulation results, the dominating direction of deformation from the parameters of aspect ratio and angle are summarized, and the equivalent relationship between the angles of the two types of structural beams is analyzed. After comparing in all aspects, the large aspect ratio and angle are selected as the basis of the structural graphic design; besides, the aluminum film with a better thermal conductivity is used as the main material of the structure. Meanwhile, the arrangement of the two structural beams is adjusted to overcome the difference of the coupling beam in the out-of-plane direction at large angles.
The experimental results show that the V-shaped structural beams, which have the maximum horizontal displacement of 16.8 μm and the maximum vertical displacement of 57.2 μm at 160°C, can be obtain. After adjusting the geometry, the difference of the coupling beam in the out-of-plane direction is reduced from 6 μm to 2 μm. However, the Z-shaped structural beam can obtain the maximum displacement of 8.5 μm and 72.3 μm in the in-plane and out-of-plane respectively. By adjusting the arrangement mode, the difference of the coupling beam in the out-of-plane direction is reduced from 8 μm to 3 μm.

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