BIT基无铅铁电薄膜1T结构铁电存储单元的保持性失效研究

项目名称： BIT基无铅铁电薄膜1T结构铁电存储单元的保持性失效研究

项目编号： No.10802072

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 金属学与金属工艺

项目作者： 钟向丽

作者单位： 湘潭大学

项目金额： 23万元

中文摘要： 本研究以新型BIT基无铅铁电薄膜1T结构为研究对象，紧紧围绕BIT基无铅铁电薄膜1T结构的制备，铁电薄膜中内应力、点电荷缺陷、电畴结构表征，电学性能和保持性失效分析等方面进行了系统的研究。通过选择合适的绝缘层材料和对1T结构以及制备工艺进行综合优化，得到了具有良好C-V存储特性、I-V漏电流特性、C-t保持性能的1T结构；建立了金属-铁电-绝缘层-半导体MFIS-1T结构的本构模型，研究了上电极与铁电薄膜的界面对1T结构存储窗口等性能的影响；建立了MFIS-1T结构的保持性能模型，探索了1T结构的保持性失效机理。 在该项目的资助下，共在影响因子2.0以上的SCI源刊上发表学术论文15篇；申请了2项国家发明专利，已经授权1项；培养了博士研究生1名，硕士研究生5名。

中文关键词： BIT基无铅铁电薄膜1T结构；保持性失效；应力；电畴；点电荷缺陷

英文摘要： One-transistor (1T) type ferroelectric memory has attracted considerable interest in recent years due to its many advantages, such as nondestructive read-out operation and small cell size. In this study, lead-free BIT-based ferroelectric film 1T structure with promising commercial application is used as the study object. The preparation, elaetrical properties and retention failure of 1T structure, and the characterization of point charge defects, internal stress, and domain of the ferroelectric film in 1T structure are studied in detail, respectively. We have obtained 1T with good C-V storage property, I-V leakage characteristics, C-t retention characteristics by selecting suitable insulator material and optimizing the fabrication processes. The constitutive model of metal-ferroelectric-insulator-semiconductor (MFIS) 1T sturcture model is developed, and the effect of the ferroelectric-electrode interface on the electrical characteristics of MFIS 1T structure is examined using this model. The retention model for MFIS 1T structure is also developed, and the possible intrinsic mechanisms of retention failure are studied. Under the support of this project, we have published 15 papers in the oroginal SCI jornals with the impact factor higher than 2.0, and have applied for 2 invention patents, one of which has been granted. In addition, great achievements have been made in the subject construction and the cultivation of talents.

英文关键词： BIT-based lead-free ferroelectric film 1T structure; retention failure; stress; domain; point charge defects