（毕业设计论文）《多晶硅薄膜晶体管特性研究》.doc

常熟理工学院毕业设计论文 PAGE 20 多晶硅薄膜晶体管特性研究 摘 要 多晶硅薄膜晶体管（polysilicon thin film transiston）因其高迁移率、高速高集成化、p型和n型导电模式、自对准结构以及耗电小、分辨率高等优点，近年来被广泛的应用于液晶显示器。随着器件尺寸减小至深亚微米，热载流子退化效应所致器件以及电路系统的可靠性是器件的长期失效问题。 本文主要研究热载流子效应。首先，研究热载流子退化与栅极应力电压，漏极应力电压及应力时间的依赖关系。其次，漏极轻掺杂（Light Doped Drain，LDD）结构是提高多晶硅薄膜晶体管抗热载流子特性的一种有效方法，研究了LDD结构多晶硅薄膜晶体管的结构参数对器件可靠性的影响。 关键词：多晶硅薄膜晶体管 热载流子效应 可靠性 Study on Characteristics of polysilicon thin film transistor Abstract Today, p-Si TFTs are used broadly in display devices because of its high field effect mobility,high integration and high speed,high definition display,n channel and p channel capability,low power consumption and self-aligned structures. With the device scaling down to deep-submicrometer, the reliability of the device circuit system induced by hot carrier effect is long-term failure. Hot carrier effects is studied. Firstly,we mainly study the dependence between hot carrier degradation and gate-stress voltage,drain-stress voltage and stress time.Secondly,the structure of Light Doped Drain is an effective means to resist hot carrier effect ,the influence of parameters of LDD structures on reliability of p-Si TFT was investigated. Keywords：p-Si TFT;hot carrier effect;reliability 目录 摘要………………………………………………………………………………………...……..I Abstract……………………………………………………..…………………………………...II 第一章 绪论……………………………………………………………………………………1 1.1薄膜晶体管的发展…………………………………………………………………………1 1.2薄膜晶体管的结构以及工作原理…………………………………………………………2 1.2.1薄膜晶体管的结构…………………………………………………………………….2 1.2.2薄膜晶体管的工作原理…………………………………………………………….…3 1.3多晶硅薄膜晶体管的应用…………………………………………………………………4 1.4多晶硅薄膜晶体管的热载流子效应………………………………………………………5 第二章 多晶硅薄膜晶体管的热载流子效应…………………………...………………6 2.1热载流子效应………………………………………………………………………………6 2.2热载流子注入栅氧化层引起的退化………………………………………………………6 2.3热载流子的注入机制………………………………………………………………..…..…7 2.4 提高多晶硅薄膜晶体管抗热载流子效应的措施……………………………………..…9 2.5本章小结…………………………………………………………………………………9 第三章 多晶硅薄膜晶体管可靠性研究………………..………………………………10 3.1多晶硅薄膜晶体管可靠性与热载流子应力条件的依赖关系……………………..10 3.1.1 阈值电压变化与栅极应力电压的关系……………………………………………10 3.1.2 阈值电压变化与漏极应力电压的关系………………………