Room-temperature photoluminescence analysis of nano-β-FeSi2/a-Si multilayer films

Abstract

Nano-β-FeSi2/a-Si layered structure was successfully deposited on Si （001） substrates using radio-frequency magnetron sputtering method. X-ray diffraction, transmission electron microscopy and photoluminescence （PL） analyses were used to characterise the structure, composition and photoluminescence properties of β-FeSi2/Si multilayer films. The results show that the peak at wavelength of 1.53 μm is observed from Fe/Si multilayer films by PL at room temperature. Without annealing, The films are of （amorphous FeSi2+ Nano-β-FeSi2 particles） / amorphous Si structure, whereas after annealing, the films are of β-FeSi2 particles/（crystal Si + amorphous Si） structure. Furthermore, the same PL intensity between as-grown and annealed samples indicates that identical luminescence property can be excited from amorphous FeSi2+β-FeSi2 particles and β-FeSi2 particles. In this experiment, the peak at wavelength of 1.53 μm is also a further indication of the semiconducting properties of amorphous FeSi2.