||Observation of Initial Stage of Nano-Scale Au Thin Film on Si(111)7×7 Surface by the PLD Method
Nakayoshi, Kohei ,
Matsunaga, Yuta ,
Yamauti, HiroshiYokotani, Atsushi
104 , 2016-07-31 , 宮崎大学工学部
As an important information for fabrication of atomic scale Au thin film which is used for biosensors, we have observed morphology of Au particles absorbed on the Si(111)7x7 surface, which is supposed to be the initial stage of Au thin film formation. Au particles were adsorbed on the Si cleaned surface using PLD method, and the adsorbed particles were observed using the scanning tunneling microscope. As the number of laser shot was increased in the PLD method, size of the adsorbed particle became larger. The larger particle were seemed to form clusters which are aggregation of particles from which each particles are distinguished, so we call this type of clusters film-shaped clusters. In this work we have mainly analyzed this type of clusters. As a result the film-shaped clusters were found to have a structure of nearly monoatomic layer. The particles in the clusters were close gathered in nearly the 3-fold structure with an inter atomic distance of 0.864 nm. We proposed a model for the cluster structure by modifying Au(111) face so that the each observed particles consists of 3 Au atoms.