Nanocrystalline Ge films created by thermal vacuum deposition on GaAs substrates: structural and electric properties

摘要

The technique of thermal vacuum deposition of Ge onto GaAs substrates hasudbeen used for obtaining nanocrystalline Ge films. Nanocrystalline character of the filmsudis confirmed by atomic force microscopy of their surface and by the data of Raman lightudscattering. The most probable size of the nanocrystallites forming the films decreasesudmonotonically with decreasing their thickness. Electro conductivity of such the filmsudproves to be high enough (1-10 Ohm·cm at room temperature) and has a character ofudvariable range hopping conduction of Mott’s type. The hops, presumably, take placeudthrough the localized states connected with the grain boundaries.