UCLA

The objective of my thesis is to use in situ low-energy electron microscopy (LEEM) and investigate the growth kinetics of monolayer graphene domains and the role of oxygen on graphene layer formation. In order to determine the growth mechanisms, LEEM images were acquired during graphene layer formation via surface segregation of carbon on single-crystalline Pd(111). Electron reflectivities and graphene growth rates were measured as a function of annealing temperature, time, and oxygen partial pressure. From the time-dependent variations in surface work function and graphene growth area, possible rate limiting processes controlling graphene layer formation were identified. Introduction of oxygen during graphene growth resulted in a lowering of graphene growth rate. And, the measured rates of graphene growth decreased with increasing oxygen partial pressure. These results provide new insights into the graphene growth kinetics and the role of oxygen.