本研究結合斜角沉積蒸鍍技術與電漿輔助化學氣相還原法，製備具有三維奈米結構之二硒化鎢，以作為氣體感測器應用之反應層。
使用斜角蒸鍍系統的目的，是為了獲得一與平片相比，具有更大表面積對體積比的三維奈米結構，從而增進應用於感測器上的能力。在此，我們選擇二硒化鎢做為一氧化氮氣體檢測的傳感材料，是由於其具P型半導體性質，且與一氧化氮分子間良好的電荷轉移現象。[1]經過參數優化後，我們的氣體偵測器顯示出高靈敏度的性能，在室溫下，對濃度為60 ppb的一氧化氮氣體有著超過40%的響應，經計算推論後，其偵測極限將達到約為15ppb。
實驗結果也顯示，在二硒化鎢中的相組成成分，將會影響其傳感表現。揭示了少量金屬相在半導體相基質中的存在，將能提升感測能力之重要性。其中，相的濃度可藉由電漿輔助硒化製程的合成溫度來調控。
另外，相較於傳統的化學氣相沉積法，電漿的輔助將能促進過渡金屬硫族化合物在較低的合成溫度下形成，顯現了其應用在可撓式電子元件製備上的潛力。

In this work, we have successfully combined the glancing angle deposition (GLAD) approach with plasma-assisted chemical vapor reduction (PACVR) method to fabricate the nano-structured tungsten diselenide (WSe2) as the reactive layer for gas sensor application.
The purpose of using GLAD system is to obtain the nanostructures with much larger surface-area-to-volume ratio compared to flat films, thus increasing the capacity for sensing application. Here we choose WSe2 as the sensing material for nitric oxide (NO) gas detection due to its p-type semiconducting property and effective charge transfer with NO molecules. [1] After parameter optimization, our sensor shows the highly sensitive performance with a response over 40% at 60 ppb at room temperature, and a derived limit of detection about 15 ppb.
We also demonstrated that the composition of phases in the WSe2 will influence the sensing behavior, revealing the importance of small amount of 1T (metallic) phase existed in the dominant 2H (semiconducting) matrix to enhance the sensing capability, where the phase concentration can be controlled by the synthesis temperature during PACVR process.
Additionally, in comparison with conventional chemical vapor deposition (CVD) processes, the assistance of plasma function facilitates the transformation of transition metal dichalcogenides (TMDCs) at lower temperatures, showing the potential for flexible devices fabrication.

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