多孔硅的制备及其发光性能的研究

发布时间：2018-04-10 18:47

本文选题：多孔硅 + 单槽电化学腐蚀法　；参考：《郑州大学》2015年硕士论文

【摘要】：硅材料是微电子技术和现代信息技术中非常重要且常用的一种半导体材料,但硅也是一种间接带隙的半导体材料,发光效率很低。多孔硅的出现解决了硅材料发光效率不理想的问题,不但使得硅的发光效率得到改善,而且可以在室温下发出肉眼可见的光致发光现象。目前为止,多孔硅(porous silicon:PS)的研究已深入到应用领域,但是仍有很多理论和实践方面的问题需要解决。多孔硅的表面形貌是影响多孔硅发光性能的主要因素之一,本文就主要研究制备条件(阴阳极之间的距离h、腐蚀反应时间t、腐蚀液浓度c、腐蚀电流密度J)改变对多孔硅的表面形貌及光致发光特性的影响。首先,简要介绍了多孔硅的发展史、制备方法、形成机理、发光机制及应用领域;接着,介绍了单槽电化学腐蚀法制备多孔硅的实验材料及仪器、实验装置及步骤,并对多孔硅的测试表征方法做了简单的介绍;采用控制变量法制备出不同腐蚀条件下的多孔硅样品,并用扫描电镜(SEM)、透射电镜(TEM)、光学显微镜及光致发光(PL)光谱对其表面形貌、发光特性进行表征,来研究不同制备条件对多孔硅的影响。研究结果显示:在改变阴阳极的距离时,出现了高质量的多孔结构以及以前没有观察到结构形貌,如火山口状结构及其周围的硅柱簇、硅纳米线结构、骨架状结构等等,并对其形成的原因做了简单的分析与介绍。扫描电镜图像显示,在样品的表面有若干个火山口一样的结构,火山口的底部出现了硅纳米线状结构,直径在几十个纳米,它的形成对以后的研究有重要的影响,为采用电化学方法制备纳米线提供了新的思路。PL光谱显示了火山口状结构与周围的多孔硅结构的发光特性,多孔硅的发光峰位在650nm左右,而火山口状结构的发光峰位在600nm左右,推测原因可能是火山口附近存在的硅纳米线组成的硅柱簇,导致了发光峰位的蓝移及发光强度的增大。为了分析以上结构形貌的形成过程,还需要进一步的研究与发现。
[Abstract]:Silicon is a very important and commonly used semiconductor material in microelectronics and modern information technology, but silicon is also a kind of indirect bandgap semiconductor material, and its luminescence efficiency is very low.The appearance of porous silicon solves the problem that the luminescence efficiency of silicon is not ideal. It not only improves the luminescence efficiency of silicon, but also emits visible photoluminescence at room temperature.Up to now, the research of porous silicon on PS has gone deep into the field of application, but there are still many theoretical and practical problems to be solved.The surface morphology of porous silicon is one of the main factors affecting the luminescence properties of porous silicon.In this paper, the effects of preparation conditions (distance between cathode and anode, corrosion time t, corrosion solution concentration c, corrosion current density J) on the surface morphology and photoluminescence characteristics of porous silicon were studied.Firstly, the development history, preparation method, formation mechanism, luminescence mechanism and application field of porous silicon are briefly introduced, and then the experimental materials and instruments, experimental devices and steps for the preparation of porous silicon by single cell electrochemical etching are introduced.The surface morphology of porous silicon samples under different corrosion conditions was investigated by SEM, TEM, optical microscope and photoluminescence (PLL) spectra.The effects of different preparation conditions on porous silicon were investigated.The results show that there are high quality porous structures when the distance between cathode and cathode is changed, and no structural morphology has been observed before, such as crater structure and its surrounding silicon cluster, silicon nanowire structure, skeleton structure, etc.The causes of its formation are also briefly analyzed and introduced.Scanning electron microscope images show that there are several crater like structures on the surface of the sample, and silicon nanowire structure appears at the bottom of the crater, with a diameter of dozens of nanometers, and its formation has an important influence on the future research.The PL spectra show the luminescence characteristics of the crater structure and the surrounding porous silicon structure. The peak position of the porous silicon is about 650nm, while the peak position of the crater structure is about 600nm.It is suggested that the existence of silicon nanowires near the crater leads to the blue shift of the luminescence peak and the increase of the luminescence intensity.In order to analyze the formation process of the above structural morphology, further research and discovery are needed.
【学位授予单位】：郑州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN304.12

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