Abstract
Surface composition saturates when metal atoms of substrate diffuse through the deposited film on the substrate and segregate on the surface of the film. Property of surface with segregation is expected to be similar to that with adsorption. Therefore, it seems possible to modify work function by segregation phenomena as well as adsorption. Saturation behavior of surface composition in segregation phenomena will be useful for easy fabrication of surface with stable work function. Therefore, work function change upon surface segregation of Cu on Ti film has been measured. Work function was measured by observing an off-set energy of secondary electrons under negative bias voltage applied to a specimen. Off-set energy was measured using a cylindrical mirror analyzer. Reduction of work function by approximately 0.3 eV was observed upon surface segregation of Cu on Ti film. This change of work function has been previously expected from the XPS results.
