Research Of The Two-dimensional Material Graphene And MoS₂ On Field-effect Transistors

The discovery of graphene opens up an extensive research on the two-dimensional material in the science filed.The novel two-dimensional materials with only a few atoms thickness has special physical and chemical properties,showing good performance in mechanical,optical,thermal and electronics,and have become the ideal selection in electronics,sensors,catalysis and energy storage,etc.Recently,the two-dimensional materials studied most are graphene and molybdenum disulfide,and they are also the core of this thesis.In this thesis,based on the excellent performance of graphene,we fabricate the graphene nanoribbon field effect transistor,and test the electrical properties.We use the conventional mechanical stripping method to prepare the graphene,SnO2 nanoribbon is synthesized by vapor-phase transport method,combined with gold film mask and SnO2 nanoribbon method to fabricate the one-dimensional nanoribbon field-effect transistors,and measured its electrical performance of the device.Conventional graphene nanoribbon(GNR)field-effect transistor fabrication involved the wet process with the separated nanoribbon formation and device fabrication.Here,we demonstrate one simple and novel non-solution method to integrate the GNR formation and the FET fabrication,the channel length and width can be controlled by the widths of the gold film and the SnO2 nanoribbon,respectively.It is found that the GNR with the width up to 330 nm presents the promising ambipolar field-effect properties and high mobility in air ambient,which benefits from the all dry process for both GNR fabrication and device fabrication.Due to the zero-band gap,it can be confined to one-dimensional to open a band gap.The width of the resulted band gap scales well with the width of GNR,which limits its switch performance.However,another two-dimensional material——MoS2,not only has many good performance of graphene,but also has a certain band gap,which can fabricate FET directly and make up the shortage of graphene.Here,we develop to improve the mechanical stripping method to prepare MoS2,increase the stripping efficiency,fabricate MoS2-FET,test its electrical performance,and outlook the property of its oxide.