Preparation and dielectric properties of highly preferred-(100) orientation (Pb, La)(Zr, Ti)O3 antiferroelectric thick films by sol-gel processing

摘要

Pb_(0.97)La_(0.02)Zr_(0.95)Ti_(0.05)5O3 (PLZT) antiferroelectric thick films of highly preferred-(100) orientation with different thickness were successfully deposited on Pt(111)/Ti/SiO2/Si(100) substrates depending on the sol-gel process technique. The effects of the PLZT thick films in the preparation and electric properties are investigated. The films show polycrystalline perovskite structure with a (100) preferred orientation by X-ray diffractometer analyses. The antiferroelectric nature of the thick films is demonstrated by P (polarization)-E (electric field). The temperature dependence of the dielectric constant and dielectric loss displays the similar behavior in both cases at 100 kHz while the values of polarization characteristic are decreased with the increase of the film thickness. The phase switching current are studied as a function of a gradually change dc electric field and the voltage dependent current density of the most highly (lOO)-oriented PLZT film is 1.49 x 10~(-8) A/cm~2 over electric field range from 0 to ±261 kV/cm. The film at 2,498 nm exhibits excellent dielectric properties and highly preferred-(100) orientation.