Synthesis and Properties of Semiconducting Iron Disilicide β-FeSi_2

概要

論文の詳細を見る
Beta-iron disilicide β-FeSi_2 bulk crystals were prepared by a horizontal gradient freeze method. The grown β-FeSi_2 bulk crystals were characterized by structural, electrical and optical measurements. The β-FeSi_2 single phase was determined by X-ray diffraction measurements. The electrical resistivity of β-FeSi_2 increased exponentially with decreasing temperature. From optical absorption spectra that were obtained from transmittance measurements, the energy band gap was determined to be 0.85 eV. The refractive index, extinction coefficient and dielectric constants were calculated using optical reflectance spectra by Kramers-Kronig analysis. In addition to β-FeSi_2 bulk materials, β-FeSi_2 films were prepared on Si(100) substrates by a laser ablation method using the above β-FeSi_2 bulk crystals as target materials. Strong Raman signals from the β-FeSi_2 films were observed at 171 cm^<-1>, 190 cm^<-1>, 199 cm^<-1> and 247 cm^<-1>,indicating deposition of well-oriented high-quality films. The optical absorption coefficient at 1.0 eV and energy band gap were determined to be 1.99 × 10^5 cm^<-1> and 0.85 eV, respectively.
社団法人応用物理学会の論文
1999-09-15