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

Coadsorption of bismuth and hydrogen on the Si(111)7×7 surface is investigated by scanning tunneling microscopy (STM) and ultraviolet photoelectron spectroscopy (UPS). Hydrogenation of the Si(111)7×7 surface is shown to change the mechanism of bismuth film growth from Stranski–Krastanov to Volmer–Weber mode. Sizes of bismuth islands and the electronic structure of the interface are found to depend on the hydrogenation degree of the silicon surface and an adsorption sequence of hydrogen and bismuth.