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Thin chromium silicide films with thickness up to 20 nm have been deposited by flash evaporation of a chromium disilicide powder on the polished silicon glass and KCl and LiF(001) substrates at temperatures from 20 to 550 C and analyzed by electrical resistance measurements during deposition as well as ex situ and ex situ TEM characterization. The film phase composition depends crucially on the deposition processing: if a chromium disilicide pre-evaporation treatment is performed just prior the deposition process, the CrSi2 film grows, otherwise film consists of Cr3Si. In both cases, under deposition onto unheated substrate an amorphous film grows. The crystalline chromium silicide phase appears at some substrate temperature (around 280C for CrSi2 and 250C for Cr3Si) and with further its increase the crystalline phase fraction continuously increases. The crystalline CrSi2 film is composed of densely packed crystallites, whereas the Cr3Si film structure is like a network of the fine crystallites imbedded into amorphous silicon matrix. The electrical properties behaviour of the films with substrate temperature is in accordance with that of their structure: after the onset of the crystalline phase growth the resistivity of the CrSi2 film increases with substrate temperature, whereas that of the Cr3Si film decreases. The observed film thickness dependence of the resistivity is well described by the Fuchs-Sondheimer model for the CrSi2 films and by the Mayadas-Shatzkes model for the Cr3Si films, because in the CrSi2 films the crystallites size (25-100 nm) is in several times greater than a film thickness,so that the film resistivity increase is caused mainly by an increased relative contribution from surface scattering, whereas in the Cr3Si films the crystallites size (2-5 nm) is fewer than a film thickness, so electrons scattering from grain boundaries contribute to further increase in resistivity. Hall measurements showed that unlike bulk CrSi2 possessing a hole conductivity, in the crystalline CrSi2 films the conductivity is realized by electrons.
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