The Hall effect in Fe submonolayer systems on n- and p-type Si(111)

The in situ Hall effect measurements at room temperature showed that format ion of the atomically clean Si(111) 7 x 7 surface as a result of high-tempe rature annealing (T = 1250 degrees C, t = 120-180 s) of n-Si reverses the m ajority carrier sign at the surface, and a hole-enriched layer is formed at the p-Si surface. The different dynamics of Hall and resistivity voltage v ariations within the first monolayer of iron adsorbed onto substrates with a p-n junction or with a hole-enriched layer is not related to conduction o ver the adsorbed layer. Conduction in the Fe layer of thickness exceeding t hree monolayers is caused in both cases by the transport of electrons with densities 2 x 10(13)-2 x 10(14) cm(-2) and mobilities 65-90 cm(2)/(V s). (C ) 2000 MAIK "Nauka / Interperiodica".