飞秒脉冲激光沉积Si基α轴择优取向的钛酸铋铁电薄膜及Ⅰ-Ⅴ特性研究  

α-axis Oriented Bi_4Ti_3O_12 Thin Films Deposited on Si(111) by Femtosecond Laser Ablation and Its Characteristic ofⅠ-ⅤCurve

作　　者：周幼华[1,2] 郑启光[1] 杨光[1] 龙华[1] 陆培祥[1] 

机构地区：[1]华中科技大学激光技术国家重点实验室,武汉430074 [2]江汉大学物理与信息工程学院

出　　处：《无机材料学报》2006年第5期1230-1236,共7页Journal of Inorganic Materials

基　　金：武汉市青年晨光计划(20035002016-15)

摘　　要：采用飞秒脉冲激光沉积系统,在Si(111)衬底上制备了a轴和c轴择优取向的Bi4Ti3O12薄膜．X射线衍射(XRD)表明:室温(20℃)下沉积的Bi4Ti3O12／Si(111)薄膜呈c轴择优取向,晶粒的平均直径为20nm．在500℃沉积的Bi4Ti3O12／Si(111)薄膜呈a轴择优取向．测量了薄膜的电滞回线和Ⅰ-Ⅴ特性曲线,并用分布参数电路研究了Bi4Ti3O12薄膜的,Ⅰ-Ⅴ特性曲线和铁电性的关联性．a轴择优取向Bi4Ti3O12薄膜的剩余极化强度Pr=15μC／cm2,矫顽力Ec=48kV／cm．The polycrystalline BiaTi3O12 thin films were successfully prepared by femtosecond laser deposition on Si（111） wafers. X-ray diffraction （XRD） showed that BiaTi3O12 thin film was highly c-axis-oriented deposited at room temperature （20℃）, but the film was highly a-axisoriented deposited at 500℃. The remanent polarization （Pr） and coercive force （Ec） of a-axisoriented samples were measured to be 15μC/cm^2 and 48kV/cm respectiovely. An equivalent circuit with distributed constants of Bi4Ti3O12/Si was introduced to interpret the relationship between the I-V characteristic curve and the ferroelectric hysteresis loop of Bi4Ti3O12 deposited on Si.

关 键 词：飞秒 脉冲激光沉积法(PLD) 钛酸铋 铁电薄膜 

分 类 号：O484[理学—固体物理]