Depth profile investigation of β-FeSi2 formed in Si(1 0 0) by high fluence implantation of 50 keV Fe ion and post-thermal vacuum annealing

A single phase polycrystalline β-FeSi2 layer has been synthesized at the near surface region by implantation in Si(100) of a high fluence (∼1017atoms/cm2) of 50keV Fe ions and subsequent thermal annealing in vacuum at 800°C. The depth profile of the implanted Fe atoms in Si(100) were simulated by the widely used transportation of ions in matter (TRIM) computer code as well as by the dynamic transportation of ions in matter code (T-DYN). The simulated depth profile predictions for this heavy ion implantation process were experimentally verified using Rutherford Backscattering Spectrometry (RBS) and X-ray Photoelectron Spectroscopy (XPS) in combination with Ar-ion etching. The formation of the β-FeSi2 phase was monitored by X-ray diffraction measurements. The T-DYN simulations show better agreement with the experimental Fe depth profile results than the static TRIM simulations. The experimental and T-DYN simulated results show an asymmetric distribution of Fe concentrated more toward the surface region of the Si substrate.