This Thesis paper explores the graphene chemical potential change based on the fabrication process and also performed a method to engineering the graphene chemical potential by electron beam exposure. In the paper, we show that the graphene Fermi level has been successfully altered from p-type to n-type by electron beam exposure. The measurement results will be posted in the later sections.;The graphene will be applied to the slot-modulator devices. The method to test the graphene chemical potential is by making a graphene-based FET, and by measuring the FET gate voltage and source-drain current, with the measurement results, we can then calculated the graphene Fermi level. The thesis also including the FET fabrication process in detail. Also, the slot-waveguide fabrications are investigated in this paper; the sub 50nm slot is a challenge for the electron beam lithography tools even the fabrication process. We used two different methods to fabricate the slot-waveguide. The graphene- based slot modulator also tested, and we find some issues and come out the solutions for them. The test bench setups and method is explained in this paper. |