Abstract (eng)
Graphene, the two-dimensional material, has gained significant attention due to its exceptional properties and the huge potential for being integrated in various future applications. In recent years, aberration-corrected scanning transmission electron microscopy (STEM) has been employed not only for atomic resolution imaging but also for defect engineering in graphene and other low-dimensional materials. In this thesis, our focus lies on investigating point defects in graphene. We begin by introducing vacancies into the graphene lattice, followed by the incorporation of Al single-atom impurities into these created defects. The characterization and analysis of these defects will be carried out using scanning transmission electron microscopy. Moreover, we utilize the focused electron probe of STEM to modify the structure of the graphene sample by manipulating and precisely repositioning embedded impurities. This work addresses the physical and instrumental limitations that can hinder successful automated single-atom manipulation in graphene, as well as generating insights on the scalability and controllability of the automated manipulation process. The thesis includes successful automated manipulation of both Si and Al single-atom impurities, along with the observation of other dynamics occurring under the electron beam during the manipulation process.