Single Crystalline Beta-FeSi2 Nanowires: Growth and Their Physical Properties

Abstract

In this work, self-catalyzed beta-FeSi2 nanowires were synthesized via chemical vapor deposition method where the fabrication of beta-FeSi2 nanowires occurred on Si(100) substrates through the decomposition of the single-source precursor of anhydrous FeCl3 powders at 650-850℃. We varied temperatures, duration time and the flow rates of carrier gases to control and investigate the growth of the nanowires. The morphology of the beta-FeSi2 nanowires was observed with scanning electron microscopy (SEM) and the structure of them was analyzed with X-ray diffraction (XRD) and transmission electron microscopy (TEM). Additionally, we have measured and discussed the properties of the silicide nanowires, including field emission, magnetism and photoluminescence. The study on beta-FeSi2 nanowires, featuring a high optical coefficient, a direct band gap of ~0.85 eV and an optical wavelength of 1.5μm, supports the development of infrared light detectors, opto-electric devices, and photovoltaics.