Quantitative analysis of Si mass transport during formation of Cu Si (111) - (5×5) from scanning tunneling microscopy

Abstract

The Si mass transport taking place during the formation of the Cu Si (111) - (5×5) surface phase has been studied using scanning tunneling microscopy. From the measurement of the areas occupied by various structural domains and the quantitative consideration of the Si mass balance, the top Si atom density in the Cu Si (111) - (5×5) phase is found to be 0.96 monolayer. The Cu Si (111) - (5×5) structure is suggested to consist of a planar CuSi overlayer with an atomic ratio of Cu:Si close to 1:1. Further Cu deposition beyond the formation of Cu Si (111) - (5×5) phase results in the formation of Cu nanocrystals on the intermediate (5×5) layer. © 2007 The American Physical Society.