Charactering The Electronic Structures And Conductivity Of Two Dimensional Organic Films

In last two decades, organic devices, such as organic light emission diodes (OLED), have been rapidly developed, and attracted lots of attention. Studies have been already done to learn about the physical properties of the interface, including the surface ordered structures, electrical characteristics of the interface and chemical identities.Surface science has become an important subject in the solid state physics, as known for its key role in the fundamental research and applications since 1960s. In this thesis, the study was carried out based on the surface science technology, the ultra violet photoemission spectroscopy (UPS), scanning tunneling microscopy (STM), and 4-point-probe (4PP) have been used to study the surface and interface properties.In chapter 1, a short review of the research background and the motivation of the PhD project were given. In chapter 2, an overall introduction of the experimental setup was established on both the working principle and the way to operate them. The electronic structure of organic molecule CoPc adsorbed on Ag(110) surface was studied in detail in chapter 3 with UPS measurement and DFT calculation. The study the CoPc adsorption on Ag/Si surface was shown, and the contribution to the surface conductivity change was concluded in chapter 4, as well as the case in varied temperatures. Finally, the fluorene-1-carboxylic acid (FC-1) on Cu(110) was studied by using STM and UPS in chapter 5, where the adsorption structure and the surface chiral of the molecule were determined, as well as the electronic structure of interface upon adsorption.