Structural and optical characterization of the formation of β-FeSi₂nanocrystallites in an n-type (100) Si matrix

Abstract

Ion-beam synthesized (IBS) samples, prepared with a low dose of iron ions and subjected to rapid thermal annealing (RTA) were studied. The samples were characterized with cross-sectional transmission electron microscopy (XTEM), including high-resolution electron microscopy (HREM) and far infrared transmittance (FIRT) spectroscopy. The formation of β-FeSi2 nanocrystallites, with various shapes and sizes, in the Si matrix was revealed. The optical constants dispersions of the samples were obtained from the reflectance (R) and transmittance (T) spectra, taken between 0.38 and 1.2 eV. From these dispersions, the energy band diagram of the interface β-FeSi2/Si was determined, and compared to those reported by other authors.

Study on the electronic structures and optical properties of -FeSi2 using the pseudopotential method

“…Therefore, β-FeSi 2 shows a quasi direct band gap. This calculated results is consistent with other theoretical calculated results [13,14]. range of -5eV～0eV, the density of states of β-FeSi 2 is mainly composed of 3d electronic states of Fe and some contributions of 3p electronic states.…”

“…First-principles simulation based on density functional theory is one of the most promising methods for predicting properties of materials [9][10][11][12][13][14][15][16][17][18]. This work uses the pseudo potential energy to calculate the band structure, the dielectric constant, absorption coefficient, refractive index, reflectivity and energy loss function of theβ-FeSi 2 .…”

Study on the electronic structures and optical properties of -FeSi2 using the pseudopotential method

“…The important features of the band structure (main band gaps and valence band widths) are given in Table 1. The overall band profiles are in fairly good agreement with previous theoretical results [19]. The valence band maximum (VBM) of 0 eV and conduction band minimum (CBM) of 0.74eV are occurs at the Y ∧ and points, as shown in table 2.…”

Correlation between impurities in Fe–Si amorphous layers synthesized by Fe implantation and photoluminescence property of β-FeSi2 precipitates in Si

“…In such a thermal treatment, however, undesirable degradation of the main parameters of Si devices can appear due to the Fe diffusion in Si. Thus, rapid SPC at high temperature by rapid thermal annealing (RTA) is preferred, in order to reduce thermal budget and suppress the Fe diffusion [7]. However, the nucleation mechanisms of b-FeSi 2 in such RTA of Fe-Si amorphous layers formed by cryogenic Fe implantation into Si substrate have not been studied in detail so far.…”