Growth of Ag islands on Si (111)-(7•7) surface

Abstract

Through the use of reflection high energy electron diffraction and scanning tunnelling microscopy, the growth behaviour of thin Ag films grown on Si substrates at room temperature has been studied. Ag islands have substantially preferred atomic scale heights and at the top in the layer-plus-island growth. Islands with two atomic layers of Ag are primarily generated at low coverage (1 ML). Strong peaks at relative heights corresponding to an even number (2,4,6) of Ag atomic layers are visible in the island height distribution at greater heights. The emergence of spiral growth and screw dislocations causes the height preference to disappear after a certain amount of coverage.