Tittle：Controlled Growth of Graphene: Toward Improved Structure, Properties & Device Performance

Speaker：Min Wang

SKKU Advanced Institute of Nanotechnology (SAINT), Samsung-SKKU Graphene Center, Sungkyunkwan University (SKKU), Korea.

时间：2013年3月11日 上午11：00-12：00
地点：北京大学深圳研究生院 G栋205室
Abstract
Graphene, a zero-gap semiconductor, has attracted considerable interest in recent years as a result of its unique band structure and physical properties, including the extremely high carrier mobility. However, there still exist challenges for graphene application in electronics. For example, how can we open graphene’s band gap without the compromise of its carrier mobility, and how can we realize its intrinsic carrier mobility in the applications? In this talk, I will introduce our work and research plans in terms of graphene growth, presenting a way to address the above-mentioned challenges. First, we directly grew large-area and smooth-edged graphene nanomesh on copper foil by nanosphere lithography, based on which the transistors show a near 3-fold higher carrier mobility than those derived from etched graphene nanomesh with the similar neck widths, because of its smoother edges. But the question is that the neck width of our grown graphene nanomesh is too large to open the band gap, which needs our further efforts. Second, we directly grew large-area and high-quality single-layer graphene on h-BN substrate, which has improved properties compared with the counterpart obtained from the transfer approach. In addition, it enables us to deeply study the graphene growth mechanism based on this novel growth behavior, which is completely contradict with the normally accepted mechanism for graphene growth on copper foil. At last, I will present some rough ideas about research plans on the deeper work to improve graphene’s structure and properties, and on the work for integrating graphene and semiconductor nanowires to combine the properties of both.
References
1. M. Wang, et al. A Platform for Large-Scale Graphene Electronics: Direct CVD Growth of Graphene on Hexagonal Boron Nitride, Adv. Mater. (Accepted)
2. M. Wang, et al. CVD Growth of Large-Area Smooth-edged Graphene Nanomesh by Nanosphere Lithography, Sci. Rep. 3, 1238; DOI:10.1038/srep01238 (2013).
3. M. Wang, et al. Tunable and Predetermined Bandgap Emissions in Alloyed ZnSxSe1-x Nanowires, Adv. Mater. 19 (2007) 4491.