Surface morphology and luminescence characterization of β-FeSi2 thin films prepared by pulsed laser deposition

beta-FeSi2 thin films were prepared on Si (1 1 1) substrates by pulsed laser deposition (PLD) with a sintering FeSi2 target and an electrolytic Fe target. The thin films without micron-size droplets were prepared using the electrolytic Fe target; however, the surface without droplets was remarkably rougher using the Fe target than using the FeSi2 target. After deposition at 600 degrees C and then annealing at 900 degrees C for 20 h, XRD indicated that the thin film prepared using the Fe target had a poly-axis-orientation, but that prepared using the FeSi2 target had a one-axis-orientation. The PL spectra of the thin films prepared using the FeSi2 and Fe targets at a growth temperature of 600 degrees C and subsequently annealed at 900 degrees C for 20 h had A-, B- and C-bands. Moreover, it was found that the main peak at 0.808 eV (A-band) in the PL spectrum of the thin films prepared using the FeSi2 target was the intrinsic luminescence of beta-FeSi2 from the dependence of PL peak energy on temperature and excitation power density. (C) 2009 Elsevier B.V. All rights reserved.