Determination of ordering induced birefringence in (Al)GaInP

In this paper, the first measurement of the ordering induced birefringence in GaInP and (Al_0.33Ga_0.67)InP is presented. It is found that these ordered crystals are positively birefringent far below the bandgap and become negatively birefringent at the bandgap. The method to measure the birefringence is based on the modifications introduced by ordering to the mode structure of planar waveguides. The change of the sign of birefringence at the bandgap is due to the highly anisotropic interband matrix element. The dispersion of the measured birefringence is in good agreement with six-band k·p calculations.     

Simultaneous impurity doping with Zn and Se in AlGaInP by MOVPE

We studied the simultaneous doping with zinc and selenium in AlGaInP by metalorganic vapor phase epitaxy. We measured the dependence of zinc and selenium incorporation on substrate orientation from (100) to (311)A faces, showing that the simultaneously doped layer becomes n-type on the (100) face and p-type on the (311)A face. The simultaneously doped layer was examined by photoluminescence, capacitance-voltage, Hall, and secondary ion mass spectrometry analysis. We showed that the simultaneously doped layers have good electrical conduction characteristics and optical qualities for cladding layers in optical devices. We also demonstrated a lateral p-n junction on a patterned substrate.     

发光二极管阵列中上隔离沟槽的设计与制备

分析了发光二极管阵列上隔离沟槽的理想尺寸。采用湿法腐蚀方法对金属层、p-GaP层及多层AlGaInP进行了逐层腐蚀，完成了宽2μm深6μm的上隔离沟槽的制作。腐蚀后的上隔离沟槽边缘平整，其深度和宽度可以解决注入电流在相邻像素之间产生的干扰问题。     

离子束刻蚀法制备大功率高效率650nm AlGaInP可见光激光器

用纯Ar离子束刻蚀方法制备出大功率高效率650nm实折射率AlGaInP压应变量子阱激光器.对偏角衬底,干法刻蚀可得到湿法腐蚀不能得到的高垂直度和对称台面.制备的激光器条宽腔长分别为4μm和600μm,前后端面镀膜条件为10%/90%.室温下阈值电流的典型值为46mA,输出功率为40mW时仍可保持基横模.10mW,40mW时的斜率效率分别为1.4W/A和1.1W/A.     

用于高亮LED的Si键合研究

在Si和外延层之间使用一层薄金属层作为高效反射镜的所谓"镜面衬底",不但有助于提高芯片的出光效率,同时把键合温度降低到300℃以下。利用Au/In合金的方法,来实现用于高亮LED的Si片与AlGaInP四元外延片的键合。实验表明,在温度为250℃时,利用Au/In作为焊料,Si片与AlGaInP四元外延片可以实现比较好的键合,键合面可以达到60%。通过研磨减薄、X-ray测试和扫描电镜(SEM)测试得出键合面的界面特性,通过能谱分析得出键合面的物质分别为AuIn2和AuIn,实验测试得出此时Au的原子数占33.31%,In的原子数占36.64%。     

GaAs基AIGaInP LED的研究和进展

探讨了GaAs基AIGaInP LED的最新研究与进展,介绍了AlGaInP红光LED外延材料的能带结构和基本的外延层结构以及限制外量子效率的问题,探讨了几种高效率的LED器件结构设计.着重介绍了目前一些外量子效率比较高的LED器件的制作方法以及一些提高外量子效率的AlGaInP LED器件结构,最后探讨了AlGaInP LED在作为固体光源发展过程中仍然需要面对的挑战.     

Mg掺杂AlInP 650 nm LD外延片的Zn扩散研究

利用石英闭管法,对Mg掺杂AlInP 650 nm LD外延片进行Zn扩散,分析了扩散温度和时间2个参数对Zn扩散的影响.采用光致发光(PL)谱和电化学蒸涂(ECV)方法研究了Zn扩散产生的影响.PL谱结果表明,Zn扩散引起了AlGaInP/GaInP多量子阱(MQW)有源层的组分无序,使PL谱的峰值蓝移,最大蓝移为54 nm,约175 meV.ECV测量结果显示,Zn已经扩散到MQW有源区,MQW区域的p型载流子浓度为4.4×1017 cm-3.     

(Al)GaInP multiquantum well LEDs on GaAs and Ge

MOVPE growth of AlGaInP layers on GaAs and Ge have been demonstrated. The surface morphology of the epilayers was smooth under optimized growth conditions. The epilayers showed good PL intensity on both GaAs and Ge substrates. It has been observed that at room temperature the PL intensity drops in the first few seconds after excitation and attains a steady state. The Zn-doped AlGaInP did not show any signs of H-passivation. The MQW LEDs on both the substrates produced electroluminescence which increased with applied current. Results indicate the feasibility of AlGaInP LEDs on Ge.     

一种新型全方位反射AlGaInP薄膜发光二极管

提出了一种新型全方位反射A1GalnP LED结构和制作工艺.GaAs外延片与含导电孔的SiO2,Au形成全方位反射镜后,银浆键合在Si支架上,去除GaAs衬底,制作薄AuGeNi电极,粗化,生长ITO,制作厚AuGeNi电极,合金则形成ODR薄膜LED结构.300μm×300μm管芯裸装在TO-18金属管座上,在20mA的电流驱动下,测得电压为2.2V,光强达到195mcd,光功率达到3.78mW,比常规吸收衬底LED提高3.6倍.     

AlGaInP系LED的表面纳米级粗化以及光提取效率提高

分析了常规AlGaInP系发光二极管（LED）光提取效率低的主要原因,半导体的折射率与空气折射率相差很大,导致全反射使有源区产生的光子绝大部分不能通过出光面发射到体外。通过在LED出光层采用纳米压印技术引入表面纳米结构,以改变光子的传播路径,从而使得更多的光子能够发射到体外。理论分析与实验结果表明,与常规平面结构相比,...