Novel high-brightness tunneling-regenerated multi-active-region AlGaInP light-emitting diode

High-brightness AlGaInP light-emitting diodes (LEDs) are becoming increasingly important and have found a variety of applications, such as outdoor displayers and automobile indicators[1—3]. Those AlGaInP LEDs can be tuned from reddish orange to yellow-green by changing Al composi-tion[1—4], since the quaternary direct band-gap material AlGaInP alloys can be precisely lattice- matched to GaAs substrate in a large range of Al composition. But the external quantum efficiency and the bri…     

实用化GaInP－AlGaInP半导体量子阱可见光激光器

用低压ＭＯＶＰＥ方法研制出了波长为６５５ｎｍ与６７０ｎｍ的ＧａＩｎＰ－ＡｌＧａＩｎＰ半导体量子阱可见光激光器，并已形成一定的批量生产能力。器件的阈值电流典型值为４５ｍＡ，输出光功率不小于５ｍＷ，最高工作温度不低于５０℃，预计２０℃时寿命接近１００，０００小时，主要技术指标与目前进口的同类产品水平相当，完全可以满足实用要求。     

AlGaInP大功率半导体激光器的漏电分析

对于GaInP/AlGaInP量子阱激光器，在大电流注入或高温工作时有源区中注入的电子会越过势垒进入p型限制层成为漏电流，严重影响器件的正常工作. 本文通过测试AlGaInP大功率压应变量子阱激光器的阈值电流和外微分量子效率随温度的变化，拟合出有源区电子的有效势垒高度，并与理论模拟结果进行了比较，讨论了p型限制层掺杂浓度的分布对势垒高度的影响.     

Thermal measurements and analysis of AlGaInP/GaInP MQW red LEDs with different chip sizes and substrate thicknesses

Thermal properties of AlGaInP/GaInP MQW red LEDs are investigated by thermal measurements and analysis for different chip sizes and substrate thicknesses. To extract the thermal resistance (R_th), junction temperature (T_j) is experimentally determined by both forward voltage and electroluminescence (EL) emission peak shift methods. For theoretical thermal analysis, thermal parameters are calculated in simulation using measured heat source densities. The T_j value increases with increasing the injection current, and it decreases as the chip size becomes larger. The use of a thin substrate improves the heat removal capability. At 450 mA, the T_j values of 315 K and 342 K are measured for 500 × 500 μm² LEDs with 110 μm and 350 μm thick substrates, respectively. For 500 × 500 μm² LEDs with 110 μm thick substrate, the R_th values of 13.99 K/W and 14.89 K/W are obtained experimentally by the forward voltage and EL emission peak shift methods, respectively. The theoretically calculated value is 13.44 K/W, indicating a good agreement with the experimental results.     

Absorption of photons in the thin film AlGalnP light emitting diode

The path of photons in the thin film(TF) light emitting diode(LED) was analyzed.The reflectivity of reflector in AlGaInP TF LED with and without the AlGaInP layer was contrasted.The absorption of the AlGaInP layer was analyzed and then the light extraction was calculated and shown in figure.The TF AlGaInP LED with 8μm and 0.6μm GaP was fabricated.At the driving current of 20 mA,the light output power of the latter is 33% higher.For the 0.6μm GaP LED,the etching of heavily doped GaP except the ohmic contact dot area is advised. The design and optimizing of current spreading between the n-type electrode and the p-type ohmic contact dot need further research.     

(Al)GaInP材料的MOCVD生长研究

对可见光半导体光电子材料Ga0．5In0．5P、(AlXGa1-x)0.5In0.5P的MOCVD生长进行了研究。使用X射线双晶衍射和PL谱测量结合的手段,研究了生长速度和生长温度对材料质量的影响。根据测试结果优化了(Al)GaInP材料的生长速度和生长温度。为研制出高性能的650nm半导体激光器打下良好的材料基础。     

基于金属背支撑刻蚀技术的柔性AlGaInP/AlGaAs/GaAs三结太阳电池研制

对柔性GaAs基太阳电池的制备方法进行研究,报道了一种用于制备柔性倒置生长的AlGaInP/AlGaAs/GaAs三结太阳电池的剥离和转移方法——金属背支撑选择性湿法刻蚀技术.在GaAs/GaInP选择性腐蚀的基础上进行了GaAs衬底层的腐蚀,研究了不同类型和体积比的溶液对GaAs/GaInP/AlInP结构腐蚀的选择特性,最终选用不同配比的H2 SO4-H2 O2系腐蚀液,获得快速、可控制、重复性好的去除衬底的两步腐蚀法.原子力显微镜测试结果表明,通过此方法能够成功地将电池外延层薄膜转移到Cu衬底上,并且在剥离和转移过程中外延层薄膜没有受到损伤.柔性AlGaInP/AlGaAs/GaAs三结太阳电池的开路电压超过3.4V.     

湿法表面粗化提高倒装AlGaInP LED外量子效率

介绍了一种利用盐酸、磷酸混合液对不同Al组分(AlxGa1-x)0.5In0.5P的选择性腐蚀特性对倒装AlGaInP红光LED进行表面粗化的方法。通过向粗化层GaInP加入适量的Al,在Al组分为0.4时,利用体积比为1∶10的HCl∶H3PO4可以得到横向尺寸约为60nm,纵向尺寸约为150nm的最有利于出光的类三角圆锥型表面结构。器件测试结果表明,在20mA注入电流下,器件外量子效率比粗化前提高了80%。     

不同集电结结构的AlGaInP/GaAs异质结双极晶体管

设计并制备了三种不同集电结结构的A lG aInP/G aA s异质结双极晶体管,计算给出了三种集电结能带结构。通过对三种HBT的直流特性测试表明,N pN型HBT因异质集电结的导带尖峰出现电子阻挡效应;N p iN型HBT集电结引入i-G aA s层能有效克服电子阻挡效应,同时还具有拐点电压Vknee小、开启电压Voffset小、击穿电压BVCEO大等优点,但由于i-G aA s层引入增加了基区电子扩散长度,使器件电流增益有所下降。