Optimizing contact resistance between graphene and different metal via double layer electrode and polymer-free transfer method

Owing to reports of graphene’s extremely high intrinsic mobility and unique structure. this thesis reviews the history on electronic property of graphene at the first, and it explains why graphene became the most popular material recently.Contact resistance is one of the important research topics among the diverse researches of graphene. In seconed part of this thesis, we discuss the contact resistance on graphene and metal., we use electron beam lithograph to fabricate the TLM pattern for reach the single crystal carrier mobility，and discuss the date by XPS and UPS .Furthermore, we compare the polymer free method with PMMA transfer to lower the contact resistance. By this method, we can use polycrystalline graphene to reach higher mobility. Thus, the results will be much better than before. Then a new double-contact geometry for graphene devices is fabricated and compared to top contacts