Fabrication and characterization of nanometer-size structures consisting of organic molecules

Overlayer structures consisting of organic molecules deposited on clean metal surfaces were observed by using scanning tunneling microscope (STM), which has sub-nanometer spatial resolution. Structural isomers of the molecules, whose difference is the binding sites of substituents, can be clearly distinguished from STM images. Introducing the substituent having attractive force, to the molecules causes specific overlayer structure by self-assembly manner controlled by the substituent. We succeeded to observe a single molecular image on a metal surface with noncontact atomic force microscope (NCAFM) that can be applicable to nonconductive sample. These techniques forming the structures and obtaining highly resolved molecular images are fundamental and essential techniques to develop future information/communication devices with molecules.