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911.
A. O. Litinski Nguyen Thi Sa 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(3):549-556
A calculation scheme based on density functional theory generalized to the case of periodic structures is used to calculate the electron energy spectrum and the imaginary part of the permittivity of single-layer 2D structures based on silicon dioxide with the surface functional groups X ≡ OH, CH3, NH2, NO2, CHO, and COOH. The dependences of the energy corresponding to the energy-band edges, valence-band widths, and the positions of the characteristic peaks of the density of states on the degree of replacement by surface groups The peculiarities of the optical absorption bands in the absorbed photon energy region ?ω < 14 eV are revealed. 相似文献
912.
M. Sridharan Sa. K. Narayandass D. Mangalaraj Hee Chul Lee 《Crystal Research and Technology》2003,38(6):479-487
Cd0.96Zn0.04Te thin films are deposited onto thoroughly cleaned glass substrates (Corning 7059) kept at room temperature by vacuum evaporation. The films are found to have good stoichiometry as analyzed by Rutherford Backscattering Spectrometry. The films exhibited zinc blende structure with predominant (111) orientation. The surface morphology of the films is studied by Atomic Force Microscopy. The rms roughness of the films evaluated by AFM is 3.7 nm. The pseudodielectric‐function spectra, ε(E) = ε1(E) + i ε2(E) at room temperature are measured by spectroscopic ellipsometry. The measured dielectric function spectra reveal distinct structures at energies of the E1, E1+ Δ1 and E2 critical points. The band gap energy of the films measured by optical transmittance measurement is 1.523 eV. The PL spectrum of the films shows intense emission due to free and bound exciton recombination and no emission associated with crystal imperfection and deeper impurity levels. The PL line shapes give indications of the high quality of the layers. 相似文献
913.
B. Karunagaran R.T. Rajendra Kumar D. Mangalaraj Sa. K. Narayandass G. Mohan Rao 《Crystal Research and Technology》2002,37(12):1285-1292
Titanium dioxide films have been deposited using DC magnetron sputtering technique. Films were deposited onto RCA cleaned p‐silicon substrates at the ambient temperature at an oxygen partial pressure of 7 × 10–5 mbar and sputtering pressure of 1 × 10 –3 mbar. The deposited films were annealed in the temperature range 673–873 K. The structure and composition of the films were confirmed using X‐ray diffraction and Auger electron spectroscopy. The structure of the films deposited at the ambient was found to be amorphous and the films annealed at 673 K and above were crystalline with anatase structure. The lattice constants, grain size, microstrain and the dislocation density of the film are calculated and correlated with annealing temperature. 相似文献