Quantum behavior of graphene transistors near the scaling limit.
The superior intrinsic properties of graphene have been a key research focus for the past few years. However, external components, such as metallic contacts, serve not only as essential probing elements, but also give rise to an effective electron cavity, which can form the basis for new quantum devices. In previous studies, quantum interference effects were demonstrated in graphene heterojunctions formed by a top gate. Here phase coherent transport behavior is demonstrated in a simple two terminal graphene structure with clearly resolved Fabry-Perot oscillations in sub-100 nm devices. By aggressively scaling the channel length down to 50 nm, we study the evolution of the graphene transistor from the channel-dominated diffusive regime to the contact-dominated ballistic regime. Key issues such as the current asymmetry, the question of Fermi level pinning by the contacts, the graphene screening determining the heterojunction barrier width, the scaling of minimum conductivity, and of the on/off current ratio are investigated.
IBM Thomas J. Watson Research Center, Yorktown Heights, New York 10598, USA. ywu@us.ibm.com
Yanqing
Y
Wu
Vasili
V
Perebeinos
Yu-ming
YM
Lin
Tony
T
Low
Fengnian
F
Xia
Phaedon
P
Avouris
D003198:Computer Simulation; D017076:Computer-Aided Design; D004579:Electron Transport; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D008956:Models, Chemical; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D014173:Transistors, Electronic
D006108:Graphite