本實驗研究二硫化鉬的拉曼光普特性,在第一章大略介紹了二硫化鉬的結構與特性, 以及近幾年二硫化鉬的應用, 還有研究動機。第二章介紹了實驗上的原理, 像是拉曼散射,二硫化鉬近幾年的研究,表面增強拉曼散射等。第三章介紹了我的光路架設以及二硫化鉬的製備。而第四章則是我的實驗數據以及分析討論。第五章就是將二硫化鉬的拉曼光普特性做個統整以及總結。
在拿到二硫化鉬的樣品之後,我們必須判斷在基板上散佈的二硫化鉬碎片的層數,於是我們利用二硫化鉬在拉曼光譜上E12g-vibration mode與A1g-vibration mode的頻率差值做為判斷二硫化鉬層數的依據,再來我們在二硫化鉬的偏振拉曼散射光譜中發現，A1g-vibration mode的強度與入射光的偏振方向有很大的關係，當入射光的偏振方向與收光的偏振方向平行時有最大值，最小值則出現在偏振方向與收光的偏振方向垂直的時候。並且在實驗中我們將該偏振的變化該偏振的變化,以間隔較小的角度變化做較為精準的分析。
在實驗中我們將二硫化鉬熱蒸鍍上銀奈米粒子後做表面增強拉曼散射光譜量測，我們發現拉曼的peak有大幅度的增長,所以在拉曼的量測上可以有效的減少該量測的時間。

In the studies of the optical characterization of MoS2 using polarized Raman spectroscopy, I use micro-Raman spectroscopy system and polarized micro-Raman system to analyze few layers MoS2, and determine the number of few layers MoS2 film by the different Raman shift between the E12g vibration mode and A1g vibration mode. After determination of few layers MoS2 film, the location of single layer, bi-layer, and tri-layer can be founded, then I research these layers (1 to 3) by using micro- polarized Raman system. I find that the A1g vibration mode of few layers MoS2 film show a strong polarization dependence, no matter which layer numbers are.
After above experimental, I use the thermal evaporator deposition system to deposit Ag films about 7 nm on the MoS2 sample. After the deposition of metal on the sample, the intensity of Raman peak of MoS2 is proved with great improvement. So, if we want to use the Raman spectra to analyze the properties of MoS2, we can deposit the metal particles on the sample to improve the efficiency of the measurement.
This thesis is organized as followed: Chapter 1 includes a brief introduction of the research background and the motivation of this experiment .In chapter 2, I introduced the research about Raman spectroscopy and few layer MoS2 film and the research about Surface Enhanced Raman Spectroscopy (SERS). In chapter 3, I describe the preparation of MoS2 and polarized micro-Raman system. In chapter 4, I introduced my experiment about the determination of few layers MoS2 film by Raman spectroscopy and the polarization dependence of MoS2 SERS spectra of few layers MoS2 film. The summary of my work are concluded in chapter 5.

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