Step-by-step monitoring of CVD-graphene during wet transfer by Raman spectroscopy.
Step-by-step monitoring of CVD-graphene during wet transfer by Raman spectroscopy.
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通过拉曼光谱逐步监测湿转移过程中的 CVD-石墨烯
作者：
转移是大规模石墨烯化学气相沉积（CVD）合成及其应用之间的关键桥梁，但石墨烯薄膜在转移过程中的质量演变仍不清楚。在这里，我们使用扫描拉曼光谱来监测在湿转移的每个步骤期间生长的石墨烯，包括浮在蚀刻剂溶液上、装载到目标衬底上以及进行额外的退火。结果表明，蚀刻剂溶液导致对浮置石墨烯的强压缩应变和p型掺杂，但在样品装载和冲洗后，特别是对于掺杂，两者均显著降低。退火处理增加了石墨烯中的压缩应变，但几乎没有增加其掺杂水平。此外，当使用聚（甲基丙烯酸甲酯）（PMMA）层来辅助转移时，它不仅增加了浮动石墨烯的p型掺杂，而且降低了退火石墨烯的结晶质量。因此，为了获得更好质量的石墨烯，除了尝试改进CVD合成以获得更大的畴尺寸之外，还必须开发通用且易于使用的无聚合物转移技术。利用拉曼光谱研究了Cu向SiO2/Si衬底湿法转移过程中石墨烯的质量变化，并分析了影响石墨烯质量变化的相关因素。
Transfer acts as a crucial bridge between the chemical vapor deposition (CVD) synthesis of large-scale graphene and its applications, but the quality evolution of a graphene film during transfer remains unclear. Here we use scanning Raman spectroscopy to monitor as-grown graphene during each step of wet transfer including floating on etchant solution, loaded onto a target substrate, and with additional annealing. Results show that the etchant solution results in strong compressive strain and p-type doping to floating graphene, but both are significantly reduced after the sample is loaded and rinsed especially for the doping. An annealing treatment increases the compressive strain in graphene but hardly its doping level. Moreover, when a poly(methyl methacrylate) (PMMA) layer is used to assist the transfer, it does not only increase the p-type doping of floating graphene but also lowers the crystalline quality of annealed graphene. Therefore, to obtain graphene with better quality, besides the attempts of improving CVD synthesis for its larger domain sizes, universal and easy-to-use polymer-free transfer techniques must be developed as well. The quality evolution of as-grown graphene during wet transfer from Cu to SiO2/Si substrate is investigated by Raman spectroscopy and the relavant factors during this process are identified.
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影响因子：
38.3
作者：
Das, A.;Pisana, S.;Sood, A. K.
通讯作者：
Sood, A. K.
影响因子：
10.8
作者：
Lin, Yung-Chang;Lu, Chun-Chieh;Chiu, Po-Wen
通讯作者：
Chiu, Po-Wen
影响因子：
10.8
作者：
Petrone, Nicholas;Dean, Cory R.;Hone, James
通讯作者：
Hone, James
影响因子：
64.8
作者：
Kim, Keun Soo;Zhao, Yue;Hong, Byung Hee
通讯作者：
Hong, Byung Hee
DOI：
10.1073/pnas.0811754106
发表时间：
2009-05-05
影响因子：
11.1
作者：
Huang, Mingyuan;Yan, Hugen;Hone, James
通讯作者：
Hone, James