掺铒富硅氮氧化硅的敏化发光研究

发布时间：2017-12-28 11:07

本文关键词：掺铒富硅氮氧化硅的敏化发光研究　出处：《浙江大学》2015年博士论文　论文类型：学位论文

【摘要】：硅基光电集成可以为微电子器件提供高速、大带宽、低串扰的光互连,因此成为目前半导体研究领域的热点之一。但是,与集成电路工艺相兼容的硅基光源的缺失是制约硅基光电集成发展的一大难点。铒离子掺杂的硅基发光材料是实现硅基光源的重要途径之一,它的制备过程与集成电路工艺兼容,其发光对应于光纤通讯的最低损耗波长,因此得到了广泛的关注。但是铒的激发截面很小,如何实现其高效发光是目前研究中亟需解决的问题。本文针对硅基掺铒富硅氮氧化硅材料,系统研究了其中铒离子的敏化机理及影响因素,对其光学性能进行一系列优化。并基于光学性能的研究,成功制备出了电致发光器件。本文的主要创新结果如下：(1) 解释了富硅量对掺铒富硅氮氧化硅薄膜中铒发光的影响,并对其进行优化。研究发现当富硅量较低时,硅纳米晶密度随富硅量提高而提高；富硅量较高时,硅纳米晶之间会相互交叠,其密度随富硅量提高而降低；同时,提高薄膜富硅量会降低光学活性铒离子的浓度。研究还发现在经过高温热处理之后,薄膜内的非辐射复合中心会被有效消除,提升富硅量并不会导致铒发光寿命的下降。所以,在中等富硅量样品中有最优的铒离子发光。(2) 发现随热处理温度的不同,在掺铒富硅氮氧化硅中存在两种敏化中心。当热处理温度低于800℃时,薄膜内没有硅纳米团簇的析出,局域态是主要的敏化中心；当热处理温度高于800℃时,局域态逐渐消亡,硅纳米团簇开始析出并成为主要敏化中心。研究发现局域态敏化铒离子浓度是硅纳米团簇的两倍以上。制约低温热处理样品中铒离子发光的主要因素是较低的荧光寿命。(3) 研究了掺铒富硅氮氧化硅的变温光致发光谱,证明其温度淬灭效应非常微弱。研究发现薄膜内存在铒离子的非辐射复合中心,其密度及能级位置随热处理条件而改变。同时发现,从局域态及硅纳米晶向铒离子传递能量的过程需要声子辅助。(4) 成功制备出开启电压低于5 V的掺铒富硅氮氧化硅电致发光器件。系统研究了器件的电输运机制,发现不同的热处理条件会改变薄膜内的缺陷态密度及能级结构。指出掺铒富硅氮氧化硅器件中铒离子的电致发光并不是由于热载流子的碰撞离化作用,而应该是一个敏化过程,这其中局域态起到了重要的作用。
[Abstract]:Silicon based optoelectronic integration can provide high speed, O Obihiro, low crosstalk optical interconnection for microelectronic devices, so it has become one of the hot topics in the field of semiconductor research. However, the lack of silicon based light source compatible with integrated circuit technology is a difficult problem that restricts the development of silicon based optoelectronic integration. Erbium doped silicon based luminescent material is one of the important ways to achieve silicon based light source. Its preparation process is compatible with integrated circuit technology, and its luminescence corresponds to the lowest loss wavelength of fiber communication, so it has attracted wide attention. However, the excitation cross section of erbium is very small, and how to realize its high efficiency luminescence is an urgent problem to be solved in the present study. In this paper, the sensitization mechanism and influencing factors of erbium ion in silicon based erbium doped silicon nitride silicon oxide materials were systematically studied, and its optical properties were optimized. Based on the study of optical properties, electroluminescent devices have been successfully fabricated. The main innovations of this paper are as follows: (1) the effect of silicon rich on Erbium emission in erbium rich silicon nitride oxide film is explained and optimized. It is found that when the silicon content is low, the density of silicon nanocrystals increases with the increase of silicon content. When the silicon content is high, the silicon nanocrystals will overlap each other, and the density will decrease with the increase of silicon content. Meanwhile, increasing the silicon content of thin films will reduce the concentration of optical active erbium ions. It is also found that after the high temperature heat treatment, the nonradiative recombination center in the thin film will be effectively eliminated. Ti Shengfu's silicon content will not lead to the decrease of Er lifetime. Therefore, there is the best erbium luminescence in the medium rich silicon. (2) it is found that there are two sensitized centers in erbium rich silicon nitrogen oxide silicon oxide with different heat treatment temperatures. When the heat treatment temperature is less than 800 degrees, there is no precipitation of silicon clusters. The localized state is the main sensitization center. When the heat treatment temperature is higher than 800 degrees, the localized state gradually disappears, and the silicon nanoclusters begin to precipitate and become the main sensitization center. It is found that the local state sensitized erbium ion concentration is more than two times that of the silicon nanocluster. The main factor that restricts the luminescence of erbium ion in the samples of low temperature heat treatment is the lower fluorescence lifetime. (3) the temperature photoluminescence spectra of erbium doped silicon rich nitrogen oxide silicon have been studied, and it is proved that the temperature quenching effect is very weak. It is found that the film is in the non radiation complex center of erbium ion, and its density and energy level change with the heat treatment conditions. It is also found that the transfer of energy from local and silicon nanocrystals to erbium ions requires phonon assistance. (4) erbium - doped silicon - rich silicon oxide electroluminescent devices with an opening voltage of less than 5 V have been successfully prepared. The electrical transport mechanism of the device is studied systematically, and it is found that the different heat treatment conditions will change the defect density and energy level structure in the thin film. It is pointed out that the electroluminescence of erbium ions in erbium doped silicon nitride silicon oxide devices is not due to the ionization ionization effect of hot carriers, but rather a sensitization process, in which the localized state plays an important role.
【学位授予单位】：浙江大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：TN383.1

【相似文献】