Structural and optical characterization of ???￠-FeSi2 layers formed by ion beam synthesis

摘要

Buried layer of semiconducting iron disilicide has been synthesized by implantation of Fe ions with an energy of 195 keV and a dose of 2x1017 Fe+/cm2 into Si(111) wafers, maintained at 500°C, followed by annealing in a N2 atmosphere at 750°C for 90 min. Rutherford Backscattering Spectrometry (RBS) and X-ray diffraction (XRD) pole figure have been used to investigate the growth and the structure of the formed iron disilicide, and the depth profile of atomic composition of Fe and Si elements. The precipitates favor epitaxial growthwith respect to Si(111) planeswith the epitaxial relationships of â-FeSi2(220)//Si(111) and /or â-FeSi2(202)//Si(111). The optical characteristics of the obtained samples have been measured at room temperature (RT) by means of Infra-Red (IR) and Raman spectroscopies, and have been correlated with the structural properties.