Optimization of the Metal Deposition Process for the Accurate Estimation of Low Metal-Graphene Contact-Resistance

Reducing the value of the contact-resistance and its precise evaluation are some of the greatest challenges related to the realization of performant graphene-based devices. The large effort made in the past years allowed to constantly reach lower and lower values of contact resistance. At this point classical evaluation techniques such as the Transfer Length Method (TLM), can be inaccurate because the growing contribution of the structure’s metal resistance can no longer be neglected. Furthermore, the realization of graphene devices using standard Si CMOS pilot lines add extra limitations on the types and maximum amount of metal that can be deposited. Keeping in mind these problematics we studied the effect that different metal depositions can have on the metal resistance values of our TLM structures. We further investigate the effects of such metal resistances can have on the evaluated value of metal-graphene contact resistance.