Amorphous-iron disilicide: A promising semiconductor

Abstract

We report here the synthesis and the measurements of the microstructural and optical properties of a promising semiconductor, amorphous-iron disilicide. The material was obtained by ion-beam mixing of Fe layers on Si, with Ar8+ ions, at 300 °C. Optical absorption measurements indicate a semiconductor with a direct band gap of 0.88 eV. The significance of this discovery is that it demonstrates the existence of such a material. It should be possible to synthesize by other techniques and could be applied in large-area electronics.

Transition from amorphous to crystalline beta phase in co-sputtered FeSi2 films as a function of temperature

“…Apart from this ␤-FeSi 2 has a high photoabsorption coefficient, about 50 times higher than crystalline Si, making it suitable for fabrication of high efficiency solar cells. 4 Recently, we have reported 5,6 the existence of another semiconductor: the amorphous form of FeSi 2 . The material was initially synthesized by ion beam mixing of Fe films on Si substrates and later confirmed by co-sputter deposition of iron and silicon.…”

Growing imbedded Ni3C-rich layer with sharp interfaces by means of ion beam mixing of C/Ni layers

“…A huge variety of metastable states can be observed ranging from miscible amorphous state [5] to the immiscible amorphous states [6,7]. The observed kinetics vary greatly too, the mass transport in limiting cases might be symmetric or asymmetric [8,9].…”

“…Ion beam mixing is far from being an equilibrium process and thus it can overcome the problem above. Really, IBM is frequently applied to produce various nonequilibrium phases like amorphous alloys with negative or positive heat of mixing [1][2][3][4][5][6][7][8][9]. To explain these phenomena it is frequently argued that the fast quenching is responsible for the process.…”

Laser patterning of thermoelectric iron silicide on alumina substrates by continuous-wave ytterbium fiber laser irradiation

“…5) For the ¢-FeSi 2 structure, an amorphous phase has also been reported. 6) Moreover, the ¢-FeSi 2 is capable of changing its conduction type when a portion of iron atoms are replaced by other transition metal atoms, i.e., the Fe 1x Mn x Si 2 is a p-type semiconductor, 7) whereas Fe 1x Co x Si 2 is an n-type semiconductor. 8) The preparation and sintering of ¢-FeSi 2 has previously been conducted by a range of methods, such as powder metallurgy and melting, 9) sputtering, 10) spark plasma sintering, 11) and YAG-laser sintering.…”