Structural Change Process of Si (100) 4 × 3-In Surface Phase Induced by Atomic Hydrogen Interaction

Abstract

We have investigated the structural change process induced by atomic hydrogen interaction with the 4 × 3 surface phase in the In/Si (100) system using scanning tunneling microscopy (STM) and coaxial impact collision ion scattering spectroscopy (CAICISS).
It has been revealed that when the 4 × 3-In surface is exposed to atomic hydrogen, small and uniform In clusters, the size of which grows with increasing substrate temperature during hydrogen exposure, are formed on the Si surface. These clusters are not epitaxially grown crystallites but amorphous or poly-crystalline in contrast with those of H/ Si (111) √3×√3-Ag, -Al or-Pb surfaces. The initial stage of structural change process is also different from H/ Si (111) √3×√3-Ag or H/Si (111) 4 × 1-In surfaces but similar to H/Si (111) √3×√3-In surface.
The In-denuded regions show not 1 × 1 but 4 × 1 periodicity. From this result, we have confirmed that the underlying atomic layer of a silicon substrate in the Si (100) 4 × 3-In surface phase is reconstructed with a 4 × 1 periodicity and proposed a model of 4 × 3-In structure.