We have studied GaAs (001) surfaces passivated with nitrogen (N) radicals at submonolayer N coverage mainly using scanning tunneling microscopy and transmission electron microscopy. We determined that GaN-rich regions are elongated in the [1̄10] direction, suggesting that N passivation proceeds in the [1̄10] direction. This can be explained in terms of minimization of the tensile strains in the  direction induced when the supplied N atoms replace first-layer As atoms on the (2×4) surface.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)