Abstract

The sensitivity of optical second-harmonic generation (SHG) to atomic and molecular monolayers absorbed on surfaces of centrosymmetric media has now been well established.¹ Recent work has also demonstrated the dependence of the SHG process on the ordering and symmetry of the surface region.² In this paper, we apply the surface SHG technique to follow in real time some widely studied and technologically important reactions occurring on clean, well-defined Si(111)-7x7 surfaces. We discuss here both the oxidation of the Si surface and the formation of thin layers of disordered and epitaxial Pd silicide.

© 1985 Optical Society of America