Contact properties to CVD-graphene on GaAs substrates for optoelectronic applications

The optimization of contacts between graphene and metals is important for many optoelectronic applications. In this work, we evaluate the contact resistance and sheet resistance of monolayer and few-layered graphene with different metallizations using the transfer length method (TLM). Graphene was obtained by the chemical vapor deposition technique (CVD-graphene) and transferred onto GaAs and Si/SiO 2 substrates. To account for the quality of large-area contacts used in a number of practical applications, a millimeter-wide TLM pattern was used for transport measurements. Different metals—namely, Ag, Pt, Cr, Au, Ni, and Ti—have been tested. The minimal contact resistance R c obtained in this work is 11.3 k Ω μ m for monolayer CVD-graphene, and 6.3 k Ω μ m for a few-layered graphene. Annealing allows us to decrease the contact resistance R c and achieve 1.7 k Ω m μ m for few-layered graphene on GaAs subs...

A V Babichev, V E Gasumyants, A Yu Egorov, S Vitusevich and M Tchernycheva

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