Photoluminescence characterization of -FeSi prepared by ion beam sputter deposition (IBSD) method

Zhuravlev, A. V.; Yamamoto, Hiroyuki; Shimura, Kenichiro*; Yamaguchi, Kenji; Shamoto, Shinichi  ; Hojo, Kiichi; Terai, Takayuki*

A semiconducting silicide, -FeSi, formed on a Si substrate, is known to exhibit strong photoluminescence (PL) peak at around 0.8 eV when it is annealed at high temperature (1073-1173 K). On the other hand, dislocation-related band of Si has intensity maxima at 0.81 eV. In the present study, the PL spectra were taken at the various stages of IBSD in order to understand the processes that are responsible for the observed PL enhancement. We observed a strong PL peak at around 0.8 eV in IBSD-grown -FeSi film on Si substrate, as well as in substrate itself, upon thermal annealing in air at 1153 K. The most pronounced peak at 0.8 eV was observed when Si substrates were sputter etched by Ne, prior to the thermal annealing in air. However, the temperature dependence of peak intensity of -FeSi was different from that of SE-treated Si, where thermal quenching appeared to occur at slightly lower temperature in the former.