Papers by Keyword: Semiconducting Silicide

Abstract: Infrared (IR) absorption and polarized Raman spectra were measured in BaSi₂ epitaxial films to investigate the vibrational modes and the symmetry of Si₄ cluster in BaSi₂. By an analysis based on Raman and/or IR activity in the spectra, the symmetry of Si₄ cluster was determined as T_h-symmetry and the observed Raman lines and IR peaks were assigned to A_g, E_g, F_g, and F_u, respectively. In the three Raman lines of F_g-mode, one LO phonon line and two TO phonon lines were classified by the depolarization ratio of polarized Raman intensities.

Abstract: Sb-doped β-FeSi₂ epitaxial films on Si(111) were grown by molecular beam epitaxy to control an electron density of β-FeSi₂. After an optimization of donor activation conditions in the Sb-doped β-FeSi₂, the electron density of 6 × 10¹⁸ cm^-3 at 300 K was achieved by thermal annealing in a N₂ ambient. In the temperature dependence of carrier density, the n-type conduction was changed to p-type conduction at low temperatures in the film annealed at high temperature (600 °C). Raman spectra of the annealed films showed that both Fe and Si sites were substituted by the doped Sb in β-FeSi₂ lattice.

Abstract: Semiconducting ruthenium silicide (Ru₂Si₃) polycrystalline thin films were grown by solid phase epitaxy using Ru-Si amorphous layers on Si substrates. The formation of Ru₂Si₃ phase was confirmed by XRD and Raman measurements when the amorphous layers were annealed at 600−900 °C in a vacuum. The Ru₂Si₃ thin films showed a low electron density of 1 × 10¹⁶ cm^-3 with a high mobility of 430−940 cm²V^-1s^-1. Photoluminescence (PL) at ~0.8 eV was observed in the Ru₂Si₃ films.

Abstract: The two groups of Ca films were directly and respectively deposited on Si(100) substrates by Radio Frequency (R.F.) magnetron sputtering system (MS) and subsequent were annealed at 600°C for 5h, 6h, 8h, 10h and 12h in a vacuum furnace. The structural and morphological features of the resultant films are tested by XRD, EDAX and FT-IR. The cubic phase Ca2Si film is grown selectively from Ca-Si system of the existence of multiple silicide phases by an interdiffusion reaction of solid phase between the deposited particles and clusters and substrate constituents. And, the structure of the deposited films, annealing temperature and annealing time are the principal factor for the selective growth.

Abstract: Semiconducting orthorhombic BaSi2 films were synthesized on Si(111) substrates using magnetron sputtering (MS) and subsequent annealing by interdiffusion between the deposited Ba film and Si(111) substrate. The structural and morphological features of the result films are analysed. The growth mechanism and the evolution of the silicides are discussed. The effects of annealing temperature and annealing time on the growth of the BaSi2 film are studied.