> 98-1

Reactivity of O2 with Si(111) Surfaces with different surface stuructures

Kazuyoshi Shimada, Tetsuya Ishimaru, Satoshi Katsube, Hiroki Kawada, and Iwao Ohdomari

Applied Surface Science, Vol. 130-132, pp.170-175, 1998.

Abstract

We tried to investigate the difference in the reactivity of O2 with Si(111) surfaces which were partly covered with the 7×7 DAS domains in the "1×1" matrix. Si(111) surface quenched from a flashing temperature down to about 765K was observed in-situ using high temperature STM with 1～5×10-9 Torr O2 exposure. The acquired sequential images clearly showed that the dark contrasts appeared preferentially in the "1×1" region and little change was observed in the 7×7 region, which indicates that oxygen preferentially


(a)

(b)

(c)

A series of STM images acquired at about 765K showing the sequential change of the surface morphology features due to oxygen exposure. (a) shows a surface before oxygen exposure. We put white lines at the fringe of each domain and copied them in the following images. (b) and (c) : Images of the surfaces (b) 105 sec, (c) 783 sec after O2 exposure