Electrical contact resistance in graphite-graphene contacts from ab initio methods

摘要

We study the ballistic transmission and the contact resistance (R-c ) of a graphite-graphene contact in a top contact geometry from first principles. We find that the calculated R-c's depend on the amount of graphene-graphite overlap, but quickly saturate for transfer lengths of the order of a few tens of angstrom. For contacts overlapping more than this transfer length, the R-c can be lower than the 100 Omega mu m(-1) mark. On the other hand, edge graphite-graphene contacts are expected to have very low contact resistance.