石墨烯薄膜的化学气相法制备及光、电特性研究

Graphene thin films fabrication with chemical vapor deposition and their optoelectronic properties

利用化学气相沉积方法制备了石墨烯薄膜,并研究了其光电特性。以乙醇做反应原料、氩气作为携载气体,在873 K、973 K、1 073 K的温度下合成石墨烯薄膜。应用光学显微镜观察,发现在1 073 K时能够制备大面积均匀、平整光滑的石墨烯薄膜。纳曼光谱分析结果表明:制备的石墨烯薄膜出现2 650 cm-1的石墨烯的特征峰-D强峰,同时该峰强度随温度的升高而迅速增强,说明低温不能使沉积的碳原子有效的石墨化为石墨烯,而较高的温度有助于乙醇分解并石墨化为石墨烯薄膜。在1 073 K时沉积的石墨烯薄膜具有良好的光、电特性,其电子迁移率可以达到104 cm2.(V.s)-1,光透射率达97%,因此,可用于制备石墨烯晶体管、太阳能电池等光电子器件。

We have fabricated grapheme thin films with chemical vapor deposition and studied their optoelectronic properties. The films were synthesized using ethanol as reactive material, and Ar gas as the carrying gas at 873 K, 973 K,and 1073 K temperatures. Through the optical microscopy,we have found that the grapheme film with large area,flat,smooth and uniform is deposited at 1 073 K. Additionally,the results of Raman spectrum analysis show that the samples have a strong, sharp characteristic peak -D peak at 2 650 cm-t. At the same time, the intensity of the D-peak is enhanced quickly with the deposition temperature increasing. This indicates that low temperature can not graphitize the deposited carbon atoms while high temperature can effectively decompose ethanol and graphitize carbon atoms to form graphene. Moreover, the graphene thin film deposited at 1 073 K is characteristics of high optoelectronic properties. The mobility of carriers is up to 104 cm^2- （V·s）^-1and the optical transmittance is over 97%. Therefore,the graphene thin film can be used to make grapheme transistor and sun energy battery.