Quasi-Periodic Nanoripples in Graphene Grown by Chemical Vapor Deposition and Its Impact on Charge Transport
详细信息 查看全文
- 作者：Guang-Xin Ni ; Yi Zheng ; Sukang Bae ; Hye Ri Kim ; Alexandre Pachoud ; Young Soo Kim ; Chang-Ling Tan ; Danho Im ; Jong-Hyun Ahn ; Byung Hee Hong ; Barbaros 脰zyilmaz
- 刊名：ACS Nano
- 出版年：2012
- 出版时间：February 28, 2012
- 年：2012
- 卷：6
- 期：2
- 页码：1158-1164
- 全文大小：1252K
- 年卷期：v.6,no.2(February 28, 2012)
- ISSN：1936-086X
文摘
The technical breakthrough in synthesizing graphene by chemical vapor deposition methods (CVD) has opened up enormous opportunities for large-scale device applications. To improve the electrical properties of CVD graphene grown on copper (Cu-CVD graphene), recent efforts have focused on increasing the grain size of such polycrystalline graphene films to 100 渭m and larger. While an increase in grain size and, hence, a decrease of grain boundary density is expected to greatly enhance the device performance, here we show that the charge mobility and sheet resistance of Cu-CVD graphene is already limited within a single grain. We find that the current high-temperature growth and wet transfer methods of CVD graphene result in quasi-periodic nanoripple arrays (NRAs). Electron-flexural phonon scattering in such partially suspended graphene devices introduces anisotropic charge transport and sets limits to both the highest possible charge mobility and lowest possible sheet resistance values. Our findings provide guidance for further improving the CVD graphene growth and transfer process.