It is a necessity to form ultra-thin films for electronic devise fabrication. Therefore, the studies of atomic structures and chemical bonding states of surfaces and interfaces of the thin films are imperative. In this laboratory, real-time in-situ observation for compound semiconductor growth and chemical reactions on semiconductors and metals has been achieved using synchrotron radiation of SPring-8. Surface atomic structure variation during GaAs growth is investigated by x-rays diffraction. Oxidation reaction dynamics of Si is also conducted by photoemission spectroscopy using supersonic molecular beam techniques.