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钛酸钡（ＢａＴｉＯ３，ＢＴ）是钙钛矿结构的铁电晶体，它具有优良的电光和非线性光学性质。用它制成的铁电薄膜在高密度的动态存储器和非易失性铁电随机存储器，介电薄膜，电光等器件有重大的实用前景。为此，人们采用诸如磁控溅射（Ｓｐｕｔｅｒｉｎｇ），金属有机物化学气相沉积（ＭＯＣＶＤ），分子束外延（ＭＢＥ），溶胶—凝胶（Ｓｏｌｇｅｌ）以及脉冲激光淀积（ＰＬＤ）等方法来制备ＢＴ薄膜。而ＰＬＤ由於具有可在氧气中原位生长薄膜，保持靶材的化学配比和成膜速率快等优点而被认为是制备多组分氧化物薄膜的最好方法之一。新近，我们首次研制成的掺铈钛酸钡晶体比纯钛酸钡晶体具有更好的光折变、铁电和电光性能。本文中我们首次报道用ＰＬＤ方法制备的Ｃｅ∶ＢａＴｉＯ３（Ｃｅ～２０ｐｐｍ）薄膜的电光性能，并和纯ＢａＴｉＯ３薄膜加以比较。用同一ＰＬＤ系统在ＳｒＴｉＯ３（１００）基片上制备ＢＴ∶Ｃｅ／ＹＢａ２Ｃｕ３Ｏ７－ｘ／ＳｒＴｉＯ３薄膜供电学测量用；在ＭｇＯ（１００）基片上制备ＢＴＧ∶Ｃｅ／ＭｇＯ和ＢＴ／ＭｇＯ薄膜供研究电光效应。用Ｘ射线衍射仪测得θ／２θ扫描谱获得Ｃｅ∶ＢａＴｉＯ３薄膜（００２）峰最大值的半宽度（ＦＷＨＭ）为０．４３°，而其（２００?
Barium titanate (BaTiO3, BT) is a perovskite-type ferroelectric crystal that has excellent electro-optical and nonlinear optical properties. The ferroelectric thin film made from it has great practical prospect in high-density dynamic memory and nonvolatile ferroelectric random access memory, dielectric film, electro-optic device. For this purpose, methods such as Sputering, Metal Organic Chemical Vapor Deposition (MOCVD), Molecular Beam Epitaxy (MBE), Sol-Gel, and Pulsed Laser Deposition (PLD) BT film was prepared. However, PLD is considered as one of the best methods for preparing multi-component oxide films because of its advantages of in-situ film growth in oxygen, keeping the stoichiometry of the target and the rate of film formation. Recently, the first cerium-doped barium titanate crystal we developed has better photorefractive, ferroelectric and electro-optical properties than pure barium titanate crystals. In this paper, we report for the first time the electro-optic properties of a Ce: BaTiO3 (Ce ~ 20ppm) thin film prepared by the PLD method and compare it with pure BaTiO3 thin films. The BT: Ce / YBa2Cu3O7-x / SrTiO3 thin films were prepared on the SrTiO3 (100) substrate by the same PLD system for electrical measurement. BTG: Ce / MgO and BT / MgO thin films were prepared on the MgO (100) substrate for the electro-optic effect. The full width at half maximum (FWHM) of the peak of the (002) peak of Ce: BaTiO3 thin film obtained by X-ray diffraction measured by θ / 2θ scan is 0.43 °,