SCANNING-TUNNELING-MICROSCOPY COMBINED QUARTZ-CRYSTAL MICROBALANCE FOR STUDY OF NH3 ADSORPTION ON AG THIN-FILM

Scanning tunneling microscopy for the observation of the surface topog raphy and quartz crystal microbalance for the micro mass measurement o f the thin film have been combined to investigate the morphology chang e of the surface of Ag thin film. Ag is evaporated on the surface of t he AT-cut quartz crystal which is oscillated at the resonance frequenc y. The mass change for the adsorption or the desorption results in a s hift in the resonance frequency. Thus the mass of the adsorption or th e desorption can be measured by detecting the frequency shift of the q uartz crystal oscillator. In situ morphology and mass changes as littl e as 320 ng cm(-2) in the NH3 adsorbed process on Ag surface are obser ved by the combined system of the scanning tunneling microscopy and th e quartz crystal microbalance. (C) 1997 Elsevier Science S.A.