Parts | Days | Selection | Search | Downloads | Help
DS: Dünne Schichten
DS 3: Schichteigenschaften I
DS 3.5: Talk
Monday, March 26, 2001, 12:00–12:15, S 5.1
Surface morphology of grain growth studied with STM — •M.J. Rost, D. Quist, and J.M.W. Frenken — Kamerlingh Onnes Laboratory, Universiteit Leiden, P.O.Box 9504 2300 RA Leiden, Netherlands
We have used scanning tunneling microscopy to investigate the thermal evolution of thin, polycrystalline gold films on a quartz substrate. The films were deposited in situ at room temperature at pressures below 10−7 mbar. The evolution was observed in ultrahigh vacuum. The microscope is an ultralow-drift UHV-STM, with which we keep track of the same location on the surface, while sweeping the temperature over e.g. 270 K.
With our special STM, we produce the first ’live’ observations of grain boundary diffusion, grain growth, film texturing (i.e. grain reorientation), and the evolution of the film flatness/roughness, with a resolution down to the atomic scale. We measure an unexpected initial flattening of the film, followed by an increase in the roughness, which we explain as the result of surface and grain boundary diffusion combined with grain boundary grooving.