Homogeneous crystalline FeSi2 films of c (4 × 8) phase grown on Si (111) by reactive deposition epitaxy

Abstract

The growth of iron silicides on Si (111) using reactive deposition epitaxy method was studied by scanning tunneling microscopy and X-ray photoelectron spectroscopy (XPS). Instead of the mixture of different silicide phases, a homogeneous crystalline film of c (4 × 8) phase was formed on the Si (111) surface at approximately 750°C. Scanning tunneling spectra show that the film exhibits a semiconducting character with a band gap of approximately 0.85 eV. Compared with elemental Fe, the Fe 2p peaks of the film exhibit a lower spin-orbit splitting (−0.3 eV) and the Fe 2p3/2 level has a smaller full-width at half maximum (−0.6 eV) and a higher binding energy (+0.3 eV). Quantitative XPS analysis shows that the c (4 × 8) phase is in the FeSi2 stoichiometry regime. The c (4 × 8) pattern could result from the ordered arrangement of defects of Fe vacancies in the buried Fe layers.

Low temperature grown highly texture aluminum alloyed iron silicide on silicon substrate for opto-electronic applications

“…Growth of iron silicides on silicon has attracted a significant attention over the past decade owing to its huge potentials for application in silicon based integrated circuits to photo-electronic devices [1][2][3][4][5][6]. Iron silicide is an interesting material which exhibits at least three different phases namely; simple cubic ɛ-FeSi 2 , tetragonal α-Fesi 2 , and orthorhombic β-FeSi 2 [4].…”

“…Iron silicide is an interesting material which exhibits at least three different phases namely; simple cubic ɛ-FeSi 2 , tetragonal α-Fesi 2 , and orthorhombic β-FeSi 2 [4]. These different phases of FeSi 2 exhibit metallic, semiconducting and insulating behavior based on their preparation conditions and structure.…”

Iron Carbidization on Thin-Film Silica and Silicon: A Near-Ambient-Pressure X-ray Photoelectron Spectroscopy and Scanning Tunneling Microscopy Study

“…For the Fe/Si sample, the formation of iron silicides has been reported when growing iron on silicon. − Iron–silicon interaction is known to lead to electron transfer from silicon to iron in iron silicides. In the Si 2p region, a shoulder at 101.8 eV (inset of Figure a) after Fe deposition is consistent with this type of interaction.…”

A simple chemical reduction approach to dope β-FeSi2 with boron and its comprehensive characterization

“…The Fe 2+ satellite peak mainly forms due to the splitting of the 2p peak owing to the exchange interaction between the antiparallel electron spin of the 2s core and 2p unlled orbitals, whereas Fe 0 peaks are due to the state where the 2s core electron spin is parallel to the 2p electron spin. 41,42 Therefore, it can be observed from Fe 2p 3 spectrum that there is a noteworthy upshi of the Fe 2+ states of both Fe 2p 3/2 and Fe 2p 1/2 peaks for B-doped samples, which can be attributed to the contraction of the Fe-B bonds, essentially due to B doping. 14,16 Besides, the FWHM of both Fe 2p 3/2 and Fe 2p 1/2 peaks becomes more and more wide mainly due to an increase in defect densities due to the tendency of B atoms to be incorporated within interstitial sites.…”