The field of molecular organic electronics is rapidly evolving, driven by the need for miniaturization and the rising complexity and costs associated with conventional semiconductor production. This shift prompts companies to explore alternatives that promise greater scalability at lower costs. Following the introduction of consumer electronics utilizing organic transistors, such as TVs and e-readers, molecular electronics is anticipated to lead to significant advancements in feature size. However, many organic/metal interfaces exhibit intrinsic defects that disrupt the uniformity of their properties. This thesis investigates the electronic and structural characteristics of these defects to understand their impact on interface quality. The primary focus is on the local properties of individual molecules, utilizing Scanning Tunneling Microscopy (STM) to realize and study molecular switches. Collaborating with theoretical groups, the research identifies and describes the mechanisms behind the switching process. Additionally, the STM's capability to construct nanostructures from large organic molecules is demonstrated. By understanding the parameters for controlling the switching process and building molecular corrals, this work paves the way for reconstructing molecular ensembles and integrating them into electrical circuits, advancing the miniaturization of electronic devices.
