Transport characteristics of multichannel transistors made from densely aligned sub-10 nm half-pitch graphene nanoribbons.
Densely aligned sub-10 nm graphene nanoribbons are desirable for scale-up applications in nanoelectronics. We implemented directed self-assembly of block-copolymers in combination with nanoimprint lithography to pattern sub-10 nm half-pitch nanoribbons over large areas. These graphene nanoribbons have the highest density and uniformity to date. Multichannel field-effect transistors were made from such nanoribbons, and the transport characteristics of transistors were studied. Our work indicates that a large ribbon-to-ribbon width variation in a multichannel FET can lead to nonsynchronized switching characters of multiple graphene channels and thus a poor ON/OFF current ratio. Through process optimization, we have created 8 nm half-pitch graphene nanoribbons with the minimal ribbon-to-ribbon width variation of ∼2.4 nm (3σ value). The corresponding transistors exhibit an ON/OFF current ratio >10, which is among the highest values ever reported for transistors consisting of densely arranged graphene nanoribbons. This work provides important insights for optimizing the uniformity and transport properties of lithographically patterned graphene nanostructures. In addition, the presented fabrication route could be further developed for the scalable nanomanufacturing of graphene-based nanoelectronic devices over large areas.
Department of Mechanical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States. xiaoganl@umich.edu
Xiaogan
X
Liang
Sungjin
S
Wi
D004579:Electron Transport; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000295:instrumentation*; D010316:Particle Size; D014173:Transistors, Electronic
D006108:Graphite