Influence of heat treatment on the structural, morphological and optical properties of DC magnetron sputtered Ti$_{x}$Si$_{1−x}$O$_2$ films

[摘要] Ti$_x$Si$_{1−x}$O$_2$ thin films were formed onto unheated p-silicon and quartz substrates by sputtering composite target of Ti80Si20 using reactive DC magnetron sputtering method. The as-deposited films were annealed in oxygenatmosphere at different temperatures in the range 400â€�??900$^{circ}$C. X-ray photoelectron spectroscopic indicated that the as-deposited films formed at oxygen flow rate of 8 sccm were of Ti$_{0.7}$Si$_{0.3}$O$_2$. X-ray diffraction studies revealed that the as-deposited films were amorphous. The films annealed at 800$^{circ}$C were exhibited broad (101) peak which indicated the growth of nanocrystalline with anatase phase of TiO$_2$. The crystallite size of the films increased from 9 to 12 nm with increase of annealing temperature from 800 to 900$^{circ}$C, respectively, due to increase in crystallinity and decrease in defect density. XPS spectra of annealed films showed the characteristic core level binding energies of the constituent Ti$_{0.7}$Si$_{0.3}$O$_2$. Optical band gap decreased from 4.08 to 3.95 eV and the refractive index decreased from 2.11 to 2.08 in the as-deposited and the films annealed at 900$^{circ}$C due to decrease in the lattice strain and dislocation density.

[学科分类] 材料工程

[关键词] Titanium silicate thin films;magnetron sputtering;X-ray photoelectron spectroscope;structure;optical properties.