ELECTROOPTIC PROPERTIES OF SOL-GEL DERIVED PZT AND PLZT THIN-FILMS

Ferroelectric(FE) films exhibit interesting electro-optic (EO) propert ies and are utilized in devices used for second harmonic generation, s patial light modulators and optical switches. These films typically yi eld large values of linear and quadratic electro-optic coefficients. S olgel derived FE films namely PZT 53/47 and PLZT 28/0/100 were prepare d on conductive glass substrates. 0.5M precursor solutions based on th e appropriate stoichiometric amounts of lead acetate, La nitrate and T i/Zr alkoxides were refluxed for 1 hour and later spincoated on the su bstrates. They were then fired to 600C to crystallize them into single phase perovskite films. Top Au/Pd electrodes were deposited to form t he top contacts for the capacitors. The refractive indices, extinction coefficients, linear and quadratic coefficients of the films were obt ained using multiangle reflection ellipsometry. These parameters were then used to calculate the linear and quadratic electro-optic coeffici ents of the films. The quadratic EO coefficients of PLZT 28/0/100 and PZT 53/47 films were measured to be 0.07 and 0.38 x 10(-16) m(2)/V-2 r espectively while the linear electrooptic coefficients of PLZT 28/0/10 0 and PZT 53/47 were found to be 59 and 315 pm/V respectively, with th e r(eff) value for PZT 53/47 the highest among reported ferroelectric films in literature.