【作者】 刘婷婷；

【导师】 王连卫；

【作者基本信息】 华东师范大学 ， 微电子学与固体电子学， 2008， 硕士

【摘要】 本文论述了基于多孔硅的三维PN结结构的形成及在核电池和X射线探测器中的应用,同时研究了此三维PN结结构的制备工艺,特别地讨论了电化学刻蚀技术形成多孔结构的工作原理,并且进行了采用SiO₂掩膜和Si₃N₄掩膜制备三维PN结结构的实验探索。第一章首先介绍了基于多孔硅的三维PN结结构的形成、应用、研究现状以及本文工作。第二章介绍了三维PN结的制备工艺,并且重点介绍了电化学刻蚀多孔硅的工作原理及其影响因素。第三章讨论了采用SiO₂掩膜的p-型半导体硅上制作宏多孔硅结构,再进行扩散制得三维PN结,探索其I-V、C-V电学性能,并且进行了孔距、孔深影响的模拟,特别是着重分析孔距（侧壁厚度）的影响。实验发现,当侧壁厚度薄到两侧的扩散层接近会聚时,孔深的提高对有效结面积影响不大。第四章详细讨论了采用低应力Si₃N₄掩膜的p-型硅上制作宏多孔硅,再进行扩散制得三维PN结。此实验重点是扩大侧壁厚度,以提高三维PN结的有效结面积。实验发现,采用抗蚀性强的低应力Si₃N₄掩膜并没有能够扩大侧壁厚度,这说明湿法刻蚀可能无法实现扩大侧壁厚度。为了解决这一问题,我们将采用深反应离子刻蚀的干法刻蚀来制作宏多孔硅,此工作还在进行中。第五章全文进行总结,并对基于三维PN结结构的能量转换芯片进行了展望。更多还原

【Abstract】 Based on the extensive research literature, the formation of 3D PN junction and the application in the fabrication of isotope batteries and X-ray detectors is explained, and the fabrication technology is also studied, specially the formation principle of porous structure fabricated by Electrochemical etching is discussed in the paper. At the same time, the fabrication experiment of 3D PN junction by the use of SiO₂ and Si₃N₄ mask.The formation, application and the research status of 3D PN junction based on macroporous silicon and the work in this thesis are firstly introduced in Chapter 1.The fabrication technology of 3D PN junction, focus on the Electrochemical etching on porous silicon and its impact factors, are described in Chapter 2.The fabrications of macroporous silicon structure on the p-type silicon by the use of SiO₂ mask and 3D PN junction by further diffusion are discussed in Chapter 3. The electrical properties are measured including IV and CV test. The impact of the hole depth is simulated and the impact of the wall thickness is specially analyzed. It was found that the increasing depth has little impact on the effective junction area when the wall thickness is so thin that the diffusion layers is close to converge.The fabrications of macroporous silicon structure on the p-type silicon by the use of Si₃N₄ mask with low stress and 3D PN junction by further diffusion are discussed in Chapter 4. It is important to increase the wall thickness to enhance the effective junction area. It was found that the wall thickness can not increase the wall thickness by the use of Si₃N₄ mask with strong corrosion resistance and low stress, indicating that wet etching may not be able to achieve increasing of wall thickness. To solve the problem, DRIE dry etching is employed to fabricate macroporous silicon. And this work is still in progress.Summary is present in Chapter 5, and prospect on the development of energy conversion chips based on 3D PN junction structure is portrayed.更多还原