Growth and Structural Properties of Indium doped SrTiO₃ Films by Pulsed Laser Deposition

Undoped and In-doped SrTiO_3(STO) films were grown on MgO/TiN/Si(100) substrates by pulsed laser deposition(PLD).The growth mechanism,crystallinity,surface morphology,and UV- Raman spectra of the films were studied.Results indicate that undoped STO films show high quality crystalline structure with highly (200) orientation.With Indium doping,the crystallinity of the STO film deteriorate,the first order Raman peaks increase indicating the breaking of crystal symmetry,and the film growth mode change from the layer-by-layer mode to island-layer mixed one,resulting in the roughening of the film surface.Furthermore,the crystallinity and (200) orientation of In-doped STO film can be enhanced significantly by introducing an undoped STO buffer layer.