Gate Dependent Raman Spectroscopy of Graphene on Hexagonal Boron Nitride
Gate Dependent Raman Spectroscopy of Graphene on Hexagonal Boron Nitride
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六方氮化硼上石墨烯的门相关拉曼光谱
DOI：
10.1088/0953-8984/25/50/505304
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发表时间：
2013
期刊：
影响因子：
--
通讯作者：
T. Taniguchi 他3名
中科院分区：
文献类型：
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作者：
C. Kanokporn;K. Watanabe;T. Taniguchi 他3名
拉曼光谱法是一种快速且无损的成像方法，可用于监测石墨烯器件中的掺杂水平。采用化学气相沉积法（CVD）在六方氮化硼（hBN）薄片和SiO2衬底上制备了石墨烯.我们比较了它们的拉曼响应作为电荷载流子密度的函数，使用离子凝胶作为顶栅。G峰位置、2D峰位置、2D峰宽度和2D峰面积与G峰面积的比率显示出与SiO2相比hBN不同的对载流子密度的依赖性。使用二维映射的直方图来比较两个衬底之间的拉曼峰特性的波动。已发现hBN衬底由于其原子级平坦表面和减少的带电杂质而在相同电荷密度下产生较少波动。
Raman spectroscopy, a fast and nondestructive imaging method, can be used to monitor the doping level in graphene devices. We fabricated chemical vapor deposition (CVD) grown graphene on atomically flat hexagonal boron nitride (hBN) flakes and SiO 2 substrates. We compared their Raman response as a function of charge carrier density using an ion gel as a top gate. The G peak position, the 2D peak position, the 2D peak width and the ratio of the 2D peak area to the G peak area show a dependence on carrier density that differs for hBN compared to SiO 2. Histograms of two-dimensional mapping are used to compare the fluctuations in the Raman peak properties between the two substrates. The hBN substrate has been found to produce fewer fluctuations at the same charge density owing to its atomically flat surface and reduced charged impurities.