Coadsorption of hydrogen and bismuth on the Si(111) 7 x 7 surface

Coadsorption of bismuth and hydrogen on the Si(1 1 1)7 x 7 surface is inves tigated by scanning tunneling microscopy (STM) and ultraviolet photoelectro n spectroscopy (UPS). Hydrogenation of the Si(111)7 x 7 surface is shown to change the mechanism of bismuth film growth from Stranski-Krastanov to Vol mer-Weber mode. Sizes of bismuth islands and the electronic structure of th e interface are found to depend on the hydrogenation degree of the silicon surface and an adsorption sequence of hydrogen and bismuth. (C) 2000 Elsevi er Science B.V. All rights reserved.