appeared in SPIE Proceeding Series, Vol. 2873, (1996) 230.
Sin-ichi Igarashi, Yukiko Abe, Takato Hirayama, and Ichiro Arakawa
Department of Physics, Gakushuin University
1-5-1, Mejiro, Toshima, Tokyo 171, Japan
We have developed a new experimental equipment for the ellipsometric study of a physisorption system on a surface of a metal single crystal; a vacuum chamber with an ultimate pressure of 10-9Pa, a substrate temperature between 40K and 1000K, and the automatic null ellipsometer. The adsorption isotherms of Xe/Ag(111) at temperatures between 60K and 80K were obtained in the wide pressure range between 10-7Pa and 10-1Pa. We found that this ellipsometer made it possible to observe layer growth of a van der Waals condensate from a submonolayer range to a thick layer where equilibrium pressure was nearly equal to the bulk saturation vapor pressure of the adsorbate.