压缩空气管路系统的设计与制作

设计与制作了一种压缩空气管路系统，该系统简易、实用，适用于替代昂贵的高压瓶装Ｎ２，充当电动控制的气动开关的气源。     

扫描电镜用于人工蛋白石模板中填充InP的形貌研究

扫描电子显微镜是对人工欧泊光子晶体进行形貌观察、研究的重要手段.本文利用扫描电子显微镜对人工欧泊晶体及其填充InP后的形貌进行了分析.结果发现,二氧化硅微球短程有序而在较大的区域则出现台阶、空位和失配等缺陷;在选定生长条件下,InP在SiO2球空隙间具有较高的填充率和较好的结晶质量.此项研究为制备三维InP光子晶体提供了科学依据.     

ZnSe-ZnS应变超晶格的光致发光

本文讨论了使用常压金属氧化物化学汽相沉积(MOCVD)技术生长的ZnSe-ZnS应变超晶格的发光特性。ZnSe-ZnS应变超晶格的发射光谱,在高密度激发下通常仅存在一个发射峰;在低密度激发下除带边发射之外,还存在深中心的发射;与低密度激发相比,高激发下发光峰值红移且其半高宽展宽,高质量的ZnSe-ZnS应变超晶格在低激发下,带边发光很强,而深中心发射能被大大抑制,我们观测到一个新的激子发射峰,考虑应变效应与量子限制效应,本文将这一新的发射峰归结为与n=1的轻空穴激子有关的复合发光。 关键词：     

LED正向压降随温度的变化关系研究

分析了LED正向压降随温度变化的物理机理,建立了恒流驱动下正向压降随温度的变化系数测试系统对不同材料、不同发射波长的LED电压随温度变化系数进行了系统的实验研究,利用最小二乘法对实验数据进行了线性拟合,得到了不同发射波长的AlGaInP、InGaN材料LED的电压随温度变化系数,对超高亮度LED、功率型LED器件及系统的热工参数测量积累了的重要数据.     

N掺杂p-型ZnO的第一性原理计算

采用基于密度泛函理论(DFT)的第一性原理平面波超软赝势方法, 计算了纤锌矿ZnO和N掺杂p-型ZnO晶体的电子结构, 分析了N掺杂p-型ZnO晶体的能带结构、电子态密度、差分电荷分布以及H原子和N2分子对p-型掺杂ZnO的影响.     

量子阱数量变化对双波长LED作用的研究

采用软件理论分析的方法分析了InGaN/GaN量子阱数量变化对双波长发光二极管发光光谱、内量子效率、电子空穴浓度分布、溢出电流等产生的影响.分析结果表明,量子阱数量的增加会引起载流子分配不均的现象,所以量子阱数量的增加并不能有效地提升载流子复合率、内量子效率和发光强度,还会引起开启电压升高的现象,影响能量转化效率.此外,不同发光波长的量子阱数量的增加会引起发光光谱强度的变化. 关键词： 量子阱 数量 数值模拟 双波长发光二极管     

量子阱数变化对InGaN/GaN发光二极管瞬态响应的影响（英文）

理论上研究了当InGaN发光二极管(LED)有源区的量子阱数变化时,LED的大信号瞬态响应特性与这种变化的关系。结果来自于LED等效电路模型的SPICE模拟,模型参数的确定通过拟合已测量的LED的实验数据及模拟结果来实现。结果表明,LED光脉冲的上升时间随量子阱数的增加而增加,由3个量子阱构成的有源区是LED的优化结构。     

Performance improvement of blue InGaN light-emitting diodes with a specially designed n-AlGaN hole blocking layer

Blue InGaN light-emitting diodes (LEDs) with a conventional electron blocking layer (EBL), a common n-AlGaN hole blocking layer (HBL), and an n-AlGaN HBL with gradual Al composition are investigated numerically, which involves analyses of the carrier concentration in the active region, energy band diagram, electrostatic field, and internal quantum efficiency (IQE). The results indicate that LEDs with an n-AlGaN HBL with gradual Al composition exhibit better hole injection efficiency, lower electron leakage, and a smaller electrostatic field in the active region than LEDs with a conventional p-AlGaN EBL or a common n-AlGaN HBL. Meanwhile, the efficiency droop is alleviated when an n-AlGaN HBL with gradual Al composition is used.     

Performance improvement of InGaN blue light-emitting diodes with several kinds of electron-blocking layers

The performance of InGaN blue light-emitting diodes(LEDs) with different kinds of electron-blocking layers is investigated numerically.We compare the simulated emission spectra,electron and hole concentrations,energy band diagrams,electrostatic fields,and internal quantum efficiencies of the LEDs.The LED using AlGaN with gradually increasing Al content from 0% to 20% as the electron-blocking layer(EBL) has a strong spectrum intensity,mitigates efficiency droop,and possesses higher output power compared with the LEDs with the other three types of EBLs.These advantages could be because of the lower electron leakage current and more effective hole injection.The optical performance of the specifically designed LED is also improved in the case of large injection current.     

The influence of AlGaN/GaN superlattices as electron blocking layers on the performance of blue InGaN light-emitting diodes

P-AlGaN/P-GaN superlattices are investigated in blue InGaN light-emitting diodes as electron blocking layers.The simulation results show that efficiency droop is markedly improved due to two reasons:(i) enhanced hole concentration and hole carrier transport efficiency in AlGaN/GaN superlattices,and(ii) enhanced blocking of electron overflow between multiple quantum-wells and AlGaN/GaN superlattices.