华东交通大学本科毕业设计(论文)格式
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LED外延片的MOCVD
指导教师：
宽禁带III－Ⅴ族氮化物半导体材料在短波长高亮度发光器件、短波长激光器、光探测器以及高频和大功率电子器件等方面有着广泛的应用前景。自1994年日本日亚化学工业公司率先在国际上突破了GaN基蓝光LED外延材料生长技术以来，美、日等国十余家公司相继报导掌握了这项关键技术，并分别实现了批量或小批量生产GaN基LED长的关键思想及核心技术仍未公开，的材料生长信息。基材料生长中的物理及化学问题，为生长可商品化的高亮度GaN基LED外延材料提供科学依据。
本文在自制常压MOCVD和英国进口MOCVD系统上对III－Ⅴ族氮化物的生长机理进行了研究，对材料的性能进行了表征。通过设计并优化外延片多层结构，生长的蓝光LED外延片质量达到了目前国际上商品化的中高档水平。并获得了如下有创新和有意义的研究结果：
1．首次提出了采用偏离化学计量比的缓冲层在大晶格失配的衬底上生长单晶膜的思想，并在GaN外延生长上得以实现。采用这种缓冲层，显著改善了GaN外延膜的结晶性能，使GaN基蓝光LED器件整体性能大幅度提高，大大降低了GaN基蓝光LED的反向漏电流，降低了正向工作电压，提高了光输出功率。
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本文得到了国家863计划、国家自然科学基金以及教育部发光材料与器件工程研究中心项目的资助。
nitrides and high brightness blue LED wafers
high temperature and high power electronic devices. Study on physics issues and technologies of nitrides open a new area of 3th generation semiconductor.
nitrides growth realized the In this atmosphere MOCVD systems. High bright blue LED wafers were obtained by optimizing the nitrides growth technology and wafer structure. Some encouraging results are following as:
1. We present the idea of using a buffer layer of deviation from stoichiometry for materials growth on large lattice mismatch substrates. This idea was realized in nitrides growth in this thesis. The epilayer crystalline quality was improved and the dislocation density was decreased by using GaN low and high temperature buffer layers of deviation from stoichiometry. The RBS/channeling spectra exhibited that the minimum yield χmin of GaN layers was just only 1.5%. The leak electric current of GaN based LED was obviously decreased and lower than 1μA at 5 volt reverse voltage by using this new buffer technology.
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This work was supported by 863 program in China.
摘要 ························································Abstract ··················································第一章 GaN基半导体材料及器件进展（多数文章为“绪论”） ······················ 1 1 .1 III族氮化物材料及其器件的进展与应用 ··················································· 1 1. 2 III族氮化物的基本结构和性质 ··································································· 4 1. 3 掺杂和杂质特性 ·························································································· 12 1. 4 氮化物材料的制备 ······················································································ 13 1. 5 氮化物器件 ·································································································· 19 1. 6 GaN·········· 22 1. 7 ·········· 24
第二章 氮化物·········· 31 2. 1 MOCVD·········· 31 2. 2·········· 32
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结论 ························································································································· 136 参考文献（References） ······················································································· 138 致谢 ························································································································· 150
族氮化物半导体材料已引起了国内外众多研究者的兴趣。 „„„„
1．2 III族氮化物的基本结构和性质
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表1-1 用不同技术得到的带隙温度系数、Eg0、c和T0的值
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„„„„ 加热电阻
―――□―――■■―――□――→气流
测温元件 测温元件
图
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华东交通大学毕业设计（论文）
第二章 氮化物MOCVD生长系统和生长工艺
2.1 MOCVD材料生长机理
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图2-1 DDS方式AWG的工作流程
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[1] Well．Multiple-modulator fraction-n divider[P]．US Patent，5038117．1986-02-02 [2] Brian Miller．
电出版社，1990．302-307．
[4] Miler．Frequency synthesizers[P]．US Patent，4609881．1991-08-06． [5] Candy J C．A use of double-integretion in sigma-delta modulation[J]．IEEE
Trans Commun，1985，33(COM)：249-258．
[6] 丁孝永．调制式小数分频锁相研究[D]．北京：航天部第二研究院，1997．
[3] - 138 -
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