Direct observation of ions in laser plume onto the substrate

Abstract
Direct observation of ions in the laser plume of YBa2Cu3O7−δ was carried out by time‐of‐flight mass spectroscopy. The direct observation of the species impinging onto the substrate is very important in order to clarify the kinetics of the film formation, so ion sampling was done through the orifice set at the position of the substrate. Thus the results indicate directly the species of ions incident onto the substrate during laser deposition. The analysis of the ion energies was also carried out. Atomic, monoxide, and cluster ions were observed in the laser plume and their energies were determined to be around 200, several tens and a few eV, respectively.