2D Material-Metal contact resistance measurement

Metal/graphene contact resistance is becoming a major limiting factor in the creation of graphene devices. In this report, we will study and refine the whole process flow towards the creation of graphene devices meant for contact resistance measurements. We first defined a new modified structure called “Modified Transmission line model” combining two different kinds of resistance measurements in order to get more reliable results. We then create different chips with different methods and tests such as dose tests in order to redefine a given process flow. We mainly improve the graphene sheet etching as well as the resist stripping in the graphene patterning process. We expose the choice of Acetone as the resist stripper instead of 1165 remover as we get more than twice as many suitable results with Acetone than 1165 remover. But we see that the main defect factor of defects in the graphene sheet is the deposition step. Finally we expose the results of contact resistivity measurements on differently created “modified TLM” devices and obtain values starting at 80 x 10-6 Ohm per centimiter square, higher than collected literature values, due to too few usable chips.