GaN基长波紫外LED多量子阱结构调整对光效的影响

发布时间：2018-04-08 12:41

本文选题：InGaN　切入点：AlGaN　出处：《西安电子科技大学》2015年硕士论文

【摘要】：随着近年来的发展,GaN基紫外LED成为继蓝光LED之后新研究领域热点和市场关注的焦点。GaN基紫外LED具有体积小、寿命长、环保以及坚固耐用等优点,在应用于新一代紫外光源方面具有广阔的的应用前景。长波段365 nm是传统紫外光源的一个典型波长,广泛应用于固化、曝光、防伪等领域。但是,目前该长波波段的GaN基紫外LED的发光效率仍然很低,发光性能还远远满足不了市场的需求,无法完全取代传统长波紫外光源。因此,对于365 nm长波波段的紫外LED进行深入的研究,开发出具有更好光电性能的器件,这对未来的紫外LED取代传统紫外光源并广泛应用于市场各领域具有十分重要的意义和影响。本论文主要研究GaN基紫外LED多量子阱结构调整对其发光效率的影响,希望通过调整使得365 nm左右波段的紫外LED发光性能得到提升。论文首先介绍了LED以及紫外LED的概况和发展情况,之后对GaN基材料的一些性质做了详细的接受,接着又对生长材料的MOCVD技术做了详细的介绍,并全面地介绍了XRD、PL、EL、AFM和SEM这些实验中用到的表征方法。最后设计实验通过调整量子阱阱宽和垒层Al掺量来实现提升发光效率的目的。两部分实验成果如下:1.对InGaN/AlGaN量子阱阱宽调整进行了两个批次实验。在保证波长在365 nm左右波段的条件下,第一个批次实验确定了2倍到5倍阱宽的发光性能优化范围,第二个批次实验则确定了3倍最优阱宽,使得外延片的发光效率最高,性能最好。最终也就得出了通过调整量子阱阱宽来提高365 nmGaN基长波紫外LED发光效率的方案结果。2.对InGaN/AlGaN量子阱垒层Al掺量调整也进行了两个批次实验。在保证波长在365 nm左右波段的条件下,在第一个批次实验中确认了垒层Al掺量在由5%变大时,发光效率变低,性能变差。在第二个批次实验中,确认了垒层Al掺量在由5%变小时,发光亮度略有变低。因此确定了垒层Al掺量控制在5%最合适。最终也就得出通过调整量子阱垒层Al掺量来提高365 nmGaN基长波紫外LED发光效率的方案结果。通过两个批次两部分的实验结果,基本实现了调整量子阱的一些结构来使得365nmGaN基长波紫外LED的光效提升,这也达到了本论文研究的目的和意义。
[Abstract]:With the development of recent years, GaN-based UV LED has become a new research hotspot and market focus after Blu-ray LED. GaN-based UV LED has many advantages, such as small size, long life, environmental protection and durability.It has a broad application prospect in the application of the new generation ultraviolet light source.Long wavelength 365nm is a typical wavelength of traditional ultraviolet light source, widely used in solidification, exposure, anti-counterfeiting and other fields.Therefore, the ultraviolet LED at 365nm wavelength has been studied deeply, and a device with better photoelectric performance has been developed.It is of great significance and influence for the future UV LED to replace the traditional UV sources and to be widely used in various fields of the market.In this paper, the effect of GaN based UV LED multiple quantum well structure adjustment on its luminescence efficiency is studied. It is hoped that the luminescence performance of UV LED at about 365nm can be improved by adjusting the structure.Firstly, the general situation and development of LED and UV LED are introduced, then some properties of GaN based materials are accepted in detail, and then the MOCVD technology of grown materials is introduced in detail.The characterization methods used in the experiments, such as SEM and ELM, are introduced in detail.Finally, we design experiments to improve the luminescence efficiency by adjusting the width of quantum well and the Al content of barrier layer.Two parts of the experiment are as follows: 1.Two batches of experiments were carried out to adjust the width of InGaN/AlGaN quantum wells.Under the condition that the wavelength is about 365 nm, the first batch experiment determines the optimal range of luminescence performance of 2 to 5 times well width, and the second batch experiment determines the optimal well width of 3 times, which makes the luminescence efficiency of the epitaxial wafer the highest.The performance is the best.Finally, the scheme of improving the luminescence efficiency of long wavelength ultraviolet LED based on 365 nmGaN is obtained by adjusting the width of quantum well.Two batch experiments were also carried out to adjust the Al content in the barrier layer of InGaN/AlGaN quantum wells.Under the condition that the wavelength is about 365 nm, it is confirmed in the first batch experiment that when the Al content of barrier layer increases from 5% to 5%, the luminescence efficiency becomes lower and the performance becomes worse.In the second batch of experiments, it was confirmed that the Al content of the barrier layer changed from 5% to a little smaller, and the luminance decreased slightly.Therefore, the optimum Al content of barrier layer is 5%.Finally, the scheme of improving the luminescence efficiency of long wavelength ultraviolet LED based on #number0# nmGaN is obtained by adjusting the Al content of quantum well barrier layer.Based on the experimental results of two batches and two parts, it is basically realized to adjust some structures of quantum wells to improve the light efficiency of 365nmGaN based long-wavelength ultraviolet LED, which also achieves the purpose and significance of this thesis.
【学位授予单位】：西安电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN312.8

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