ITO厚度对AlGaInP发光二极管特性的研究

采用金属有机物化学气相沉积技术在GaAs衬底上生长AlGaInP红光发光二极管器件,在表层GaP上沉积氧化铟锡透明导电层,使用扫描电镜分析器件外观、透射电镜观察器件各层结构、半导体测试机测试其光电参数、回流焊验证器件的热稳定性、X射线光电子能谱分析氧化铟锡透明导电层中In、O元素化合态;研究了不同氧化铟锡透明导电层厚度对器件光电参数、热稳定性、发光角度的影响,结果表明随着氧化铟锡透明导电层厚度增加器件电压降低、发光亮度先增加后下降,热稳定性随厚度增加而变好,发光角度随厚度增加而减小。     

隧道结AlGaInP发光二极管

报道了通过隧道结将衬底的导电类型从n型转变到p型,从而可以利用n型GaP作为以n型GaAs为衬底的AlGaInP发光二极管的电流扩展层.n型电流扩展层的电阻率低于p型电流扩展层的电阻率,这种结构改善了电流扩展层的作用,从而提高了发光二极管的光提取效率.对3μm GaP电流扩展层的发光二极管,实验结果表明,隧道结发光二极管的发光功率与具有相同基本结构的传统发光二极管相比,20mA时发光功率提高了50%,100mA时提高了66.7%.     

AlGaInP light-emitting diodes with SACNTs as current-spreading layer

Transparent conductive current-spreading layer is important for quantum efficiency and thermal performance of light-emitting diodes (LEDs). The increasing demand for tin-doped indium oxide (ITO) caused the price to greatly increase. Super-aligned carbon nanotubes (SACNTs) and Au-coated SACNTs as current-spreading layer were applied on AlGaInP LEDs. The LEDs with Au-coated SACNTs showed good current spreading effect. The voltage bias at 20 mA dropped about 0.15 V, and the optical power increased about 10% compared with the LEDs without SACNTs.     

Improved light extraction of wafer-bonded AIGaInP LEDs by surface roughening

By using the wafer bonding technique and wet etching process, a wafer bonded thin film AlGaInP LED with wet etched n-AlGaInP surfaces was fabricated. The morphology of the etched surface exhibits a pyramid-like feature. The wafer was cut into 270× 270 μm2 chips and then packaged into TO-18 without epoxy resin. With 20-mA current injection, the light intensity and output power of LED-I with surface roughening respectively reach 315 mcd and 4.622 mW, which was 1.7 times higher than that of LED-II without surface roughening. The enhancement of output power in LED-I can be attributed to the pyramid-like surface, which not only reduces the total internal reflection at the semiconductor-air interface but also effectively guides more photons into the escape angle for emission from the LED device.     

AlGaInP LEDs with surface anti-reflecting structure

he new LEDs are especially suitable for working at large injected currents.     

Investigation of distributed Bragg reflector growth conditions for high‐brightness AlGaInP light‐emitting diodes

Abstract— The effect of growth conditions of a distributed Bragg reflector (DBR) structure on the performance of AlGaInP light‐emitting diodes (LEDs) have been investigated. Increasing the growth temperature and the flow rate of AsH₃ as well as lowering the growth pressure resulted in improved reflectivity and root‐mean‐square (RMS) roughness of the high‐aluminum‐content multiple pairs of the DBR structure. An increase in the growth temperature may improve the mobility of atoms on the surface for the positioning of the right atomic site and to reduce oxygen incorporation. An increase in the flow rate of AsH₃ can suppress the arsenic vacancy formation at higher V/III ratios. Furthermore, reduction in growth pressure can suppress the convection flow on the epitaxial growth surface. To verify the influence of DBR growth conditions on the successive growth of LED structures, the growth of full LED structures having two different DBR growth conditions was performed, and AlGaInP red LEDs using full LED structures were fabricated. It was found that higher growth temperature and AsH₃ flow rate with lower growth pressure for the DBR structure produced improved output power of the AlGaInP LEDs, which can be attributed to the high reflectivity and low RMS roughness of the DBR structure.     

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6 5 0 nm实折射率Al Ga In P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4 μm和6 0 0 μm,前后端面镀膜条件为10 % / 90 % .室温下阈值电流的典型值为4 6 m A,输出功率为4 0 m W时仍可保持基横模.10 m W,4 0 m W时的斜率效率分别为1.4 W/ A和1.1W/ A.     

Donor-acceptor interactions in Al0.5In0.5P

Dopant interactions are considered between Mg-acceptor atoms and various donor species, including the deep donor; oxygen; and the shallow donors, Te, S, and Si, in Al_0.5In_0.5P. While each of these donor species is shown to suppress Mg diffusion and enhance Mg incorporation in Al_0.5In_0.5P, careful analysis of the concentration profiles for these various donor species reveals subtle differences in the shape of the donor and acceptor dopant profiles, suggesting subtle differences in both the type of donor-acceptor interactions involved and in the effectiveness of the various donor species at suppressing Mg diffusion. Oxygen, in particular, is shown to have a profound effect on Mg diffusion in Al_0.5In_0.5P uniform-composition layers, while other donor species are less effective at suppressing Mg diffusion. Such differences suggest that a chemical bonding effect or complex formation may be more dominant between Mg and oxygen, while electrical compensation likely plays a larger relative role between Mg and the shallow-donor species.     

Correlation between dark current RTS noise and defects for AlGaInP multiple-quantum-well laser diode

推导了AlGaInP多量子阱LD器件暗电流RTS 噪声与缺陷相关性模型,实验结果表明暗电流RTS 噪声由有源区异质结界面载流子数涨落引起。根据相关性模型,确定了缺陷类型,定量确定了缺陷能级。分析了暗电流RTS 噪声功率谱密度的转角频率。实验结果和理论预测一致。本文结论提供一种确定AlGaInP多量子阱LD器件有源区深能级的有效方法。