INFLUENCE OF THE ION IRRADIATION ON THE PROPERTIES OF BETA-FESI2 LAYERS PREPARED BY ION-BEAM-ASSISTED DEPOSITION

beta-FeSi2 layers on Si substrates were produced by ion beam assisted deposition (IBAD). The influence of the deposition parameters on the s tructure was studied by Rutherford backscattering, X-ray diffraction, cross-section transmission electron microscopy, and scanning electron microscopy, The layers grow in a columnar way with pin-holes and their surface is rough. An IBAD process with low Ar energy (E-Ar = 200 eV) and low Ar ion to Fe atom ratio (I-Ar/A(Fe) = 0.15) improves the layer structure in comparison to samples prepared without Ar irradiation. L ess pin-holes are formed, and the roughness shows a minimum. The rough ness increases for larger values of E-Ar or I-Ar/A(Fe). All samples ar e polycrystalline but with a pronounced texture. The preferential orie ntation FeSi2(110,101)parallel to Si(001), with a few degrees misorien tation, is found. This preferred grain orientation is also enhanced by the IBAD process, Hall effect measurements were done and the I-V char acteristics of the samples were measured. The results are discussed in relation with the influence of the ion beam.