In-situ Preparation And Preparation Methods' Improvement Of Two-Dimensional Materials

Since the successful preparation of two-dimensional materials like graphene,two-dimensional materials have expanded from graphene to a series of two-dimensional materials through the development of 20 years.Such as two-dimensional hexagonal boron nitride(h-BN),transition metal dichalcogenides(TMDs),main group chalcogenides(MCs),metal organic frameworks(MOFs),and group III,group IV and group V single element two-dimensional material(Xene),etc.They have different structures and properties,like the photoelectric effect,superconductivity,and the topological property,etc.It is very beneficial for the growth of high quality new two-dimensional materials by using the Molecular Beam Epitaxy(MBE)equipment.The sample can also be transferred in-situ to the Scanning Tunneling Microscopy(STM)to test the surface morphology and physical properties of two-dimensional materials.We need to choose the suitable substrate to grow the two-dimensional materials.Combining two-dimensional materials with oxide substrates may bring more novel properties.Therefore,it is necessary to realize the growth of two-dimensional materials by using an oxide substrate in a molecular beam epitaxy chamber.And the main results are shown below:1.Based on the scanning tunneling microscopy-molecular beam epitaxy(STM-MBE)equipment and the pulsed laser deposition-molecular beam epitaxy(PLD-MBE)equipment,we designed the DC heating devices to heat the oxide substrate.2.By using the DC heat devices,we achieved the good surface of Nb-SrTiO3.We grew the film of MoTe2 and SnSe2 on the surface of Nb-SrTiO3.We also scanned the surface topography and tested the physical properties of them.3.Based on the existing DC heating device,a further improvement scheme is proposed.The magnetic rod is used to realize the movement in the Z-axis direction and the 360-degree rotation around the Z-axis.In the PLD-MBE equipment,We change the sample plate to hollow and the heating device can heat the substrate by DC current and laser.