bi3.15nd0.85ti3o12铁电薄膜成分纵深分布及掺杂改性分析.docx

极化又分别增大和减小,掺杂量 x 为 时,薄膜具有最平整光滑的表面和最大
的剩余极化强度(2Pr 为 );薄膜漏电流随着 Zr 掺杂浓度的增加而明显减小,当掺杂量 x 为 时,在高电压区域(高于 3 V), 薄膜的漏电流相对 BNT 薄膜的漏电流低四个数量级;B 位 Zr 离子掺杂几乎没有改变 BNT 薄膜的居里温度,薄膜居里温度约为 450℃。
关键词:BNT 铁电薄膜;组分纵深分布;掺杂;漏电流;化学溶液沉积
Abstract
In the 1990’s, with the rapid development of microelectronics puter industry, non-volatile ferroelectric thin film memory has attracted much attention due to its high memory density, fast read/write speed, good radiation hardness and non-volatile characteristic. At present, the materials used to prepare ferroelectric thin film memory are mainly PZT series because they have some favorable properties, such as large remnant polarization (Pr) value and low processing temperature. However, PZT films have some serious drawbacks, such as poor fatigue endurance and harm to the environment. As people are paying more and more attention to the environment, it es very important to find a new kind of lead-free ferroelectric material with excellent ferroelectric property to replace PZT. (BNT) is currently regarded as one of the most promising candidate materials for ferroelectric thin film memories due to its lead-free position, low processing temperature, large Pr value and excellent fatigue endurence. In this work, BNT lead-free ferroelectric thin films were deposited. positional depth profiles and chemical states of the elements at different film depth of prepared BNT films were investigated in detail. In addition, the effects of B-site substitution by Zr ion in BNT film were studied. The main research contents and obtained results in this thesis are summarized as follows:
BNT lead-free ferroelectric thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates by a chemical solution deposition (CSD) method. positions, surface morphologies, composition depth profiles, chemical states of film elements and electrical properties of BNT films were investigated in detail by X-ray diffraction, atomic force microscopy,