The goal of this thesis is to investigate the possibilities of building a GHz compatible circuit that will allow high frequency measurements with a Scanning Tunneling Microscope. In this frequency...Show moreThe goal of this thesis is to investigate the possibilities of building a GHz compatible circuit that will allow high frequency measurements with a Scanning Tunneling Microscope. In this frequency range, many interesting properties of materials could be accessed, as for example shot noise in the tunneling current. The main problem in these kinds of measurements is the mismatch between the very high impedance of the tunneling junction and the 50 Ω impedance of the measurement circuitry, which causes the high frequency signal to be reflected back. Here, two solutions to this problem - lumped and distributed impedance matching - are theoretically described and simulated in order to determine their advantages and disadvantages. Lastly, a distributed resonating circuit is built and measured, with the purpose of investigating potential difficulties in distributed circuits on a PCB.Show less
In this thesis, the viability of the construction of a nanogap between two graphenesheets has been researched. Several methods of electrode-fabrication have been analyzed. Two techniques have been...Show moreIn this thesis, the viability of the construction of a nanogap between two graphenesheets has been researched. Several methods of electrode-fabrication have been analyzed. Two techniques have been identified as viable candidates, namely the MCBJ and the reactive ion-etching method. The results of Atomic Force Microscope analysis for both methods showed graphene reaching all the way up to the edge of the substrate. The MCBJ-method was further researched by performing the breaking of a Si/SiO2-wafer, under different ambient conditions. These results point to the possibility of overhanging patches of graphene contacting the underlying Si wafer, giving characteristic semiconductor IV-curves.Show less
