Effect of ion energy on structural and chemical properties of tin oxide film in reactive ion-assisted deposition (R-IAD)

Tin oxide films were deposited on in-situ heated Si (100)substrates using reactive ion-assisted deposition and the effect of average impinging energy of oxygen ions on the crystalline structure and the stoichiometry of deposited films were examined. The transformation from SnO phase to SnO2 phase of the films was dependent on the change of the average impinging energy of oxygen ion (E-a) and the relative arrival ratio of oxygen to tin. Perfect oxidation of SnO2 was performed at E-a= 100, 125 eV/atom at as low as 400 Angstrom substrate temperature. The composition (N-o/N-Sn) of films increased from 1.21 to 1.89, and was closely related to the average impinging energy of oxygen ion. The surface morphology of the films was also investigated by scanning electron microscopy.