Graphene is a distinct 2D material which attracts scientists since its discovery in 2004. However, the presence of extrinsic disorders has been a major problem for fabricating high quality graphene devices. In this thesis, a dry transfer technique was developed to fabricate high quality monolayer graphene heterostructures (BN/Graphene/BN) and their electronic properties were subsequently investigated.

Unique methods and structural designs were employed to protect graphene from direct contact with solvent and polymers, which are contaminants commonly introduced using traditional transfer techniques. Besides, preparation and identification procedures were optimized to shorten the fabrication period. Device structures of FETs and QC capacitances on graphite were designed and fabricated...[ Read more ]

Graphene is a distinct 2D material which attracts scientists since its discovery in 2004. However, the presence of extrinsic disorders has been a major problem for fabricating high quality graphene devices. In this thesis, a dry transfer technique was developed to fabricate high quality monolayer graphene heterostructures (BN/Graphene/BN) and their electronic properties were subsequently investigated.

Unique methods and structural designs were employed to protect graphene from direct contact with solvent and polymers, which are contaminants commonly introduced using traditional transfer techniques. Besides, preparation and identification procedures were optimized to shorten the fabrication period. Device structures of FETs and QC capacitances on graphite were designed and fabricated to test the reliability of these techniques.

The ballistic transport verified the effectiveness of these methods (carrier mobility reached 195,000 cm²V^-1s^-1 and 500,000 cm²V^-1s^-1 at 300K and 2K, respectively). Landau Level splitting in Quantum Hall Effect phenomenon was observed in both FET and quantum capacitance devices at low magnetic field. Furthermore, negative compressibility in quantum capacitance was detected.

Collectively, the pick-up dry transfer technique and the sandwich configuration are reliable and effective to fabricate high quality graphene devices. The ultra-clean system offers an opportunity to unravel physical phenomena, which were previously interfered by impurities and defects. With the successfulness in fabricating high quality graphene, the general use of the dry transfer technique in manufacturing potential electronic devices can be expected.