本研究製備二硫化鉬與二硒化鉬材料，以氧氣電漿轟擊材料表面，再分別製作成場效電晶體元件，同樣以氧氣電漿轟擊元件通道或電極底下接觸之材料，探討其表面形貌變化與光電特性改變。研究分為以下部分討論材料之變化：表面形貌、元素組成與光電特性。
在第一部分研究中，會以原子力顯微鏡、SEM與TEM觀察轉移後與氧氣電漿轟擊後，二硫化鉬與二硒化鉬形貌改變，同時利用拉曼與PL確認材料的層數。在表面形貌變化部分，使用氧電漿10瓦，3, 6和9秒的時間處理材料，發現材料在3秒時有最小的表面粗糙度，進行至6秒與9秒後，材料會開始出現破損和奈米捲現象。
第二部分元素組成中，以拉曼分析材料特徵峰會隨時間降低，6秒以後測量不到二硫化鉬、二硒化鉬與三氧化鉬的特徵峰。從XPS分析可以得知，隨著氧電漿轟擊時間增長，Mo4+的峰值會逐步轉換成Mo6+；從STEM影像分析可以瞭解在氧電漿處理後，雖然材料有破損與裂痕，但還可以確認到二硫化鉬與二硒化鉬晶格，表面也沒有分析到三氧化鉬的繞射點與拉曼訊號。
第三部分光電特性方面，分別量測：轉移後未處理二維材料元件、氧電漿轟擊通道元件、電漿預先處理電極底部的接觸材料。從電性結果可以確認氧電漿轟擊後會造成材料缺陷增加，氧電漿轟擊通道元件的光電流與光響應度會隨著處理時間增加而下降；預處理會有清潔效果使電阻率下降，但如果元件製作殘留有機物少則電阻率不會有顯著減少，而較長的轟擊時間反而會使電阻率升高。
透過實驗分析證實，以氧氣電漿轟擊二硫化鉬與二硒化鉬材料表面，會造成缺陷增加甚至形成奈米捲導致材料破損，使材料導電度下降，同時改變開關電流值與閾值電壓。

In this study, molybdenum disulfide and molybdenum diselenide materials were synthesized. The surfaces of these materials underwent treatment with oxygen plasma, followed by the fabrication of field-effect transistors. Subsequently, the channels or materials under the electrodes were bombarded to investigate surface morphology. The study is structured into three sections focusing on the changing of the materials: surface morphology, composition, and photoelectrical properties.
In the first part of the study, use Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM) to observe the morphological alterations of molybdenum disulfide and molybdenum diselenide before and after exposure to oxygen plasma treatments. Additionally, Raman spectroscopy (Raman) and Photoluminescence (PL) techniques will be utilized to verify the number of layers present. The surface morphology was modified using oxygen plasma treatment at power levels of 10 watts for durations of 3, 6, and 9 seconds. It was observed that the material exhibited the least surface roughness at 3 seconds. After 6 and 9 seconds, the material underwent structural changes leading to the formation of nanorolls.
In the latter part of the elemental composition analysis, the characteristic peaks of the materials analyzed by Raman decrease over time. Specifically, the peaks associated molybdenum disulfide, molybdenum diselenide, and molybdenum trioxide are no longer detectable after 6 seconds. Through X-ray photoelectron spectroscopy (XPS) analysis, it is evident that with an increase in the duration of oxygen plasma treatment , the intensity of the Mo4+ will gradually transitions to Mo6+. Despite the damage incurred by the materials, the crystal lattice of molybdenum disulfide and molybdenum diselenide remains observable. Notably, no diffraction pattern corresponding to molybdenum trioxide was discernible on the surface.
In the third section, the photoelectrical characteristics were assessed for the following samples: the untreated two-dimensional material, devices channel after oxygen plasma treatments, and the treatments on materials under electrodes. It was observed that the oxygen plasma treatment led to an increase in defects. Furthermore, currents and photoresponsivity of devices subjected to channel treatments decreased with longer processing time. Resistivity (ρ) also decreases slightly after the treatments on materials under electrodes (plasma cleaning).
Experimental analysis has verified that bombarding the surface of molybdenum disulfide and molybdenum diselenide materials with oxygen plasma results in the augmentation of defects and even the formation of nanorolls, ultimately resulting in material degradation.

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