Deposition of Strontium Barium Niobate Thin Films by Metal-Organic Chemical Vapor Deposition and Their Nonlinear Optical Properties

ABSTRACTSingle phase, highly textured strontium barium niobate (SBN) thin films were deposited by low pressure metal-organic chemical vapor deposition on both crystalline and amorphous substrates. The metal precursors employed were niobium pentaethoxide as well as barium and strontium (hexafluoroacetylacetonate)2•tetraglyme. SBN thin films with compositions across the entire solid solution range were deposited. The nonlinear optical properties of the SBN films were also measured. Nonlinear optical coefficients approaching bulk values were obtained for as-deposited oriented films. The room temperature, effective second-order nonlinear coefficient was 3.0 pm/V. Films with the highest degree of crystalline perfection had the largest effective nonlinear coefficient. The second harmonic intensity was strongly temperature dependent with a maximum at the ferroelectric transition.