Abstract
Photon with the energy of 1eV has the infrared wave length. However, it corresponds to the thermal energy of about 11600°K. Therefore, photo-chemistry can induce chemical reactions with very high activation energy. Moreover, the radicals or ions of a single sort are induced as a result of irradiation of light source with a single wave length. Therefore, the induced chemical reaction is specified even with impure materials.
The measurement for the identification of a radicals or ions concerned in the reaction is also another merit of the photo-reactions.
In this paper, photo-assisted chemical reactions are explained and the molecular layer epitaxy, which made the crystal growth accurate in the order of single atomic dimensions, is explained, followed by the effect of ultra-violet light irradiations. These methods are also valuable to clarify surface adsorbed phenomena and also its reactions. Some experimental results are explained.
