Determination resistance of metal contacts fabricated on graphene by TLM method

While Graphene Field Effect Transistor is fabricated, metal electrical contacts are deposited on graphene to provide electrical transmission. Each metal has different specific contact resistance. Low-quality metal contacts cause performance killer effect and remove high performance of promising material, graphene. Therefore, forming high quality ohmic contacts to graphene is essential in terms of science. In this thesis Indium/Gold (8/20 nm), Cadmium/Gold (8/30 nm) and Chrome/Gold-Germanium (3/50 nm) contacts are made on the graphene and in terms of electrical conduction the contact quality is determined from TLM measurements. The spesific contact resistivity was found as 1800 Ωµm for Indium/Gold contact, 1475 Ωµm for Chrome/Gold contact and 546 Ωµm for Cadmium/Gold contact, respectively. When reviewing the literature, Cadmium/Gold contact seem to be quite promising material. Furthermore, it was found that spesific resistance of Cadmium/Gold contact shows independent characteristics from the applied gate voltage.