Ion beam synthesis of IrSi{sub 3} by 1-MeV Ir ion implantation into Si(111)

The formation of a Si/IrSi{sub 3}/Si heterostructure by 1-MeV Ir ion implantation and subsequent annealing has been studied for different doses (0.1--2.25 {times} 10{sup 17} Ir/cm{sup 2}), substrate temperatures (450--600C) and annealing temperatures (1000--1200C) using Rutherford backscattering spectrometry, ion channeling and cross-sectional transmission electron microscopy. The heterostructure formation is observed to depend strongly on the processing conditions. The best structure, nearly continuous and precipitate-free, is obtained by implanting 1.8--2.0 {times} 10{sup 17} Ir/cm{sup 2} at a substrate temperature of 550C and annealing at 1100C for 5 h. A stoichiometric IrSi{sub 3} layer can also be produced by furnace annealing at 1150C for 1 h or by rapid-thermal-annealing at 1200C for 3 min. Other substrate temperatures generally lead to a structure with a discontinuous IrSi{sub 3} layer frequently interrupted by large surface precipitates or islands. Origin of these islands, as well as dependence of heterostructure on processing parameters, is discussed

Structure of thin CrSi2 films on Si(0 0 1)

The morphology and texture of CrSi2 films grown on Si(0 0 1) is reported. The films have been prepared under ultra high vacuum conditions by reactive codeposition and by the template method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses have been performed to investigate the influence of the substrate temperature and the template thickness on the silicide texture and morphology. XRD evidences that the major part of CrSi2 crystallites grows with an orientation of View the MathML source within all present experiments. Considering the morphology and preferred orientation of the crystallites the substrate temperature of 700 °C is determined to be optimal for the codeposition growth method. A further improvement of the CrSi2(0 0 1) texture and an increase of the grain size by an order of magnitude is observed after deposition of 0.5 nm Cr onto the Si(0 0 1) substrate at room temperature prior to the codeposition of Cr and Si at 700 °C