Abstract
One dimensional transition metal silicide nanostructures have attracted much attention for their potential applications in electronic and optoelectronics nanodevices as well as for their intriguing physical properties different from those of bulk materials. In the present research, we report the growth and structural characterization of the self-catalyzed iron silicide nanowires. In addition, the specific optical, electrical and magnetic properties of the nanowires were also investigated. A spontaneous chemical reaction method was used for the fabrication of the iron silicide nanowires. The possible growth mechanism and the variables that affect the nanowire growth were also discussed. The as-synthesized β-FeSi2 nanowires exhibit photoluminescence at a wavelength of 1.54 μm, which is suitable for the Si-based optical communication, at room temperature. In addition, the room temperature ferromagnetism and high magnetoresistance performance indicates that β-FeSi2 nanowires are potentially applicable for spintronic nanodevices. On the other hand, the room-temperature ferromagnetism of the as-grown FeSi nanowires compared to that of bulk FeSi at 4 K was found. The fabricated memory devices based on FeSi nanowires showed significant C-V hysteresis, exhibiting the memory effect. The strong memory effect can be accounted for by the presence of defects or dangling bonds on the surface of the FeSi nanowires embedded in SiO2 layer, which enhances the trapping density for non-volatile memory applications.