skip to main content

Title: Transition metal contacts to graphene

Achieving low resistance contacts to graphene is a common concern for graphene device performance and hybrid graphene/metal interconnects. In this work, we have used the circular Transfer Length Method (cTLM) to electrically characterize Ag, Au, Ni, Ti, and Pd as contact metals to graphene. The consistency of the obtained results was verified with the characterization of up to 72 cTLM structures per metal. Within our study, the noble metals Au, Ag and Pd, which form a weaker bond with graphene, are shown to result in lower contact resistance (Rc) values compared to the more reactive Ni and Ti. X-ray Photo Electron Spectroscopy and Transmission Electron Microscopy characterization for the latter have shown the formation of Ti and Ni carbides. Graphene/Pd contacts show a distinct intermediate behavior. The weak carbide formation signature and the low Rc values measured agree with theoretical predictions of an intermediate state of weak chemisorption of Pd on graphene.
Authors:
; ;  [1] ;  [2] ; ; ; ; ; ; ;  [3] ;  [4] ;  [3] ;  [5]
  1. KU Leuven, 3001 Leuven (Belgium)
  2. (Belgium)
  3. imec, Kapeldreef 75, 3001 Leuven (Belgium)
  4. SAIT, Samsung Electronics Co., Suwon 443-803 (Korea, Republic of)
  5. (United States)
Publication Date:
OSTI Identifier:
22482253
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 15; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CARBIDES; CHEMISORPTION; ELECTRON SPECTROSCOPY; GRAPHENE; PERFORMANCE; TRANSITION ELEMENTS; TRANSMISSION ELECTRON MICROSCOPY; X RADIATION