GaN纳米线光电阴极电子结构和光学性质的第一性原理研究

发布时间：2018-03-29 04:07

  本文选题：GaN纳米线　切入点：光电阴极　出处：《南京理工大学》2017年硕士论文

【摘要】：GaN光电阴极是紫外光电倍增管、紫外探测器等光电子器件的重要组成部分,在公安、航天、高能物理领域等领域有着广阔的应用前景。目前对GaN纳米线在光电阴极材料应用方面的研究还未见报道,亟待进一步的探索。在本文中,基于密度泛函理论(DFT)的第一性原理计算方法被用于从微观层面分析研究GaN纳米线的电子结构和光学性质,为GaN纳米线光电阴极制备工艺提供了理论指导和基础。本文主要内容分为四个部分。第一部分介绍了第一性原理的理论基础和计算方法,对CASTEP软件包也做了简单介绍。第二部分介绍了本征GaN纳米线光电阴极方面的研究,包括对其相关计算的收敛性测试、不同截面尺寸GaN纳米线光电阴极的性质研究和表面H原子钝化对GaN纳米线光电阴极的影响。选取了较大尺寸并经过H钝化处理的GaN纳米线光电阴极作为计算的合理模型。第三部分介绍了对p型掺杂GaN纳米线光电阴极的相关研究,确定了 Mg原子为合适的掺杂元素,并分析了不同位置Mg掺杂对纳米线光电阴极性质的影响,以此指导p型GaN纳米线光电阴极的制备。第四部分介绍了 N空位缺陷对本征GaN纳米线光电阴极和Mg掺杂GaN纳米线光电阴极的作用,结果表明N空位的存在是制备高质量GaN纳米线光电阴极的重要阻碍,是下阶段实验研究工作的一大重点。
[Abstract]:GaN photocathode is an important part of photoelectron devices such as ultraviolet photomultiplier tube, ultraviolet detector and so on. The research on the application of GaN nanowires in photocathode materials has not been reported, and it needs further exploration. The first-principle calculation method based on density functional theory (DFT) is used to analyze the electronic structure and optical properties of GaN nanowires at the microcosmic level. The main contents of this paper are divided into four parts. The first part introduces the theoretical basis and calculation method of the first principle. In the second part, the research on intrinsic GaN nanowire photocathode is introduced, including the convergence test of the related calculation. The properties of GaN nanowire photocathodes with different cross-sectional sizes and the effect of surface H atom passivation on GaN nanowire photocathodes are studied. The GaN nanowire photocathodes with larger size and H passivation treatment are selected as the calculated combination. The third part introduces the research of p-doped GaN nanowire photocathode. The effect of mg doping on the photocathode properties of nanowires was analyzed. In order to guide the preparation of p-type GaN nanowire photocathodes, the effects of N-vacancy defects on intrinsic GaN nanowire photocathodes and mg doped GaN nanowire photocathodes are introduced in the fourth part. The results show that the existence of N vacancy is an important hindrance to the preparation of high quality GaN nanowire photocathodes.
【学位授予单位】：南京理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O462;TN304

【参考文献】

相关期刊论文 前5条

1 吴东旭;郑学军;程宏斌;李佳;罗晓菊;;不同生长方向的GaN纳米线的可控制备与性能表征[J];人工晶体学报;2015年02期

2 李拥华,徐彭寿,潘海滨,徐法强,谢长坤;GaN(100)表面结构的第一性原理计算[J];物理学报;2005年01期

3 谢自力,张荣,修向前,毕朝霞,刘斌,江若琏,沈波,顾书林,韩平,朱顺明,施毅,郑有p，

本文编号：1679471