键合方法研制InAsP/InGaAsP量子阱1.3μm垂直腔面发射激光器

设计并研制了由InAsP/InGaAsP应变补偿多量子阱有源层、SiO2/TiO2介质薄膜和GaAs/Al(Ga)As半导体分布布拉格反射镜(DBR)构成的垂直腔面发射激光器(VCSEL).采用直接键合技术实现InP基有源层与GaAs基DBR的晶片融合,并经过侧向湿法腐蚀定义电流限制孔径和沉积介质薄膜DBR等关键器件工艺,研制出InAsP/InGaAsP量子阱垂直腔面发射激光器,其阈值电流为13.5mA,单模激射波长为1288.6nm.     

键合方法研制InAsP/InGaAsP量子阱1.3μm垂直腔面发射激光器

设计并研制了由InAsP/InGaAsP应变补偿多量子阱有源层、SiO2/TiO2介质薄膜和GaAs/Al(Ga)As半导体分布布拉格反射镜（DBR）构成的垂直腔面发射激光器（VCSEL) . 采用直接键合技术实现InP基有源层与GaAs基DBR的晶片融合,并经过侧向湿法腐蚀定义电流限制孔径和沉积介质薄膜DBR等关键器件工艺,研制出InAsP/InGaAsP量子阱垂直腔面发射激光器,其阈值电流为13.5mA,单模激射波长为1288.6nm.     

InGaAs/GaAs多量子阱SEED面阵结构特性与设计

讨论了谐振腔中的 DBR对 In Ga As/ Ga As多量子阱 SEED面阵光反射特性的影响 .采用 In Ga As/ Ga As作为多量子阱 SEED器件的有源区 ,从而获得了 980 nm工作波长 .设计和分析了 In Ga As/ Ga As多量子阱 SEED中的一种用于倒装焊的新型谐振腔结构 .多量子阱材料是用 MOCVD系统生长 ,利用微区光反射谱、PL 谱以及 X射线双晶衍射对多量子阱材料进行了测量和分析 ,测量结果表明多量子阱材料具有良好的质量 ,证明了器件结构的设计和分析是准确的     

InGaN/AlGaN双异质结绿光发光二极管

报道了用 LP- MOVPE技术在蓝宝石 ( α- Al2 O3)衬底上生长出以双掺 Zn和 Si的 In Ga N为有源区的绿光 In Ga N/Al Ga N双异质结结构 ,并研制成功发射波长为 52 0— 540 nm的绿光LED.     

掺Si对AlGaInP/GaInP多量子阱发光性能的影响

研究了Si掺杂对MOCVD生长的(Al0.3Ga0.7)In0.5P/Ga0.5In0.5P多量子阱发光性能的影响.样品分为两类:一类只生长了(Al0.3Ga0.7)In0.5P/Ga0.5In0.5P多量子阱结构;另一类为完整的多量子阱LED结构.对于只生长了(Al0.3Ga0.7)In0.5P/Ga0.5In0.5P多量子阱结构的样品,掺Si没有改变量子阱发光波长,但使得量子阱发光强度略有下降,发光峰半高宽明显增大.这应是掺Si使量子阱界面质量变差导致的.而在完整LED结构的情况下,掺Si却大大提高了量子阱的发光强度.相对于未掺杂多量子阱LED结构,垒层掺Si使多量子阱的发光强度提高了13倍,阱层和垒层均掺Si使多量子阱的发光强度提高了28倍,并对这一现象进行了讨论.     

808nm InGaAlAs垂直腔面发射激光器的结构设计

为实现垂直腔面发射半导体激光器(VCSEL)在808 nm波长的激射,对VCSEL芯片的整体结构进行了设计。基于应变量子阱的能带理论、固体模型理论、克龙尼克-潘纳模型和光学传输矩阵方法,计算了压应变InGaAlAs量子阱的带隙、带阶、量子化子能级以及分布布拉格反射镜(DBR)的反射谱,从而确定了量子阱的组分、厚度以及反射镜的对数。数值模拟的结果表明,阱宽为6 nm的In0.14Ga0.74Al0.12As/Al0.3Ga0.7As量子阱,在室温下激射波长在800 nm左右,其峰值材料增益在工作温度下达到4000 cm-1;渐变层为20 nm的Al0.9Ga0.1As/Al0.2Ga0.8As DBR,出光p面为23对时反射率为99.57%,全反射n面为39.5对时反射率为99.94%。设计的顶发射VCSEL结构通过光电集成专业软件(PICS3D)验证,得到室温下的光谱中心波长在800 nm处,证实了结构设计的正确性。     

HCl/HF/CrO3溶液对 InGaAs/InGaAsP的选择性湿法刻蚀--应用于楔形结构的制备

利用动态掩膜湿法腐蚀技术,研究了HCl/HF/CrO3溶液对与InP衬底晶格匹配的InxGa1-xAs1-yPy(y=0,0.2,0.4,0.6)材料的腐蚀特性.对于HCl(36wt%)/HF(40wt%)/CrO3(10wt%)的体积比为x∶0.5∶1的溶液,随着x由0增加到1.25,相应的腐蚀液对In0.53Ga0.47As/In0.72Ga0 28As06P0.4的选择性由42.4降到1.4;通过调节腐蚀液的选择性,在In072Ga0.28As06P0.4外延层上制备出了倾角从1.35°到35.9°的各种楔形结构;当x为0.025和1.25时,相应的In0.72Ga0.28As0.6P0.4腐蚀表面的均方根粗糙度分别为1.1nm和1.6nm.还研究了溶液的组分与InxGa1-xAs1-yPy(y=0,0.2,0.4)的腐蚀速率间的关系,并对腐蚀机理进行了分析.     

HCl/HF/CrO3溶液对InGaAs/InGaAsP的选择性湿法刻蚀——应用于楔形结构的制备

利用动态掩膜湿法腐蚀技术，研究了HCl/HF/CrO3溶液对与InP衬底晶格匹配的InxGa1－xAs1－yPy(y=0,0.2,0.4,0.6)材料的腐蚀特性．对于HCl(36wt%)/HF(40wt%)/CrO3(10wt%)的体积比为x∶0.5∶1的溶液，随着x由0增加到1.25，相应的腐蚀液对In0.53Ga0.47As/In0.72Ga0.28As0.6P0.4的选择性由42.4降到1.4；通过调节腐蚀液的选择性，在In0.72Ga0.28As0.6P0.4外延层上制备出了倾角从1.35°到35.9°的各种楔形结构；当x为0.025和1.25时，相应的In0.72Ga0.28As0.6P0.4腐蚀表面的均方根粗糙度分别为1.1nm和1.6nm．还研究了溶液的组分与InxGa1－xAs1－yPy(y=0,0.2,0.4)的腐蚀速率间的关系，并对腐蚀机理进行了分析．     

(Al) Ga InP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。     

AlGaInP红、橙、黄光高亮度LED外延材料

采用金属有机化合物汽相淀积技术生长用于高亮度发光管 (UB-L ED)的 Al Ga In P/Ga As半导体微结构材料 ,突破了材料结构设计和材料生长工艺的关键技术 ,生长出满足于 Cd级的红、橙、黄光 L ED器件的外延材料。     

高反射性电流阻挡层用于提高InGaN/GaN发光二极管的光输出功率

由SiO₂/TiO₂分布布拉格反射镜(DBR)和Al镜组成的混合式反射电流阻挡层用于提高InGaN/GaN发光二极管的光输出功率。混合式反射电流阻挡层不仅增强了电流扩展效应而且有效的将射向p金属电极的光子反射防止其对p电极焊点附近光子的吸收。实验结果表明,淀积在p-GaN上1.5个周期的SiO₂/TiO₂DBR和Al镜在455nm垂直入射时的反射率高达97.8%。在20mA的工作电流下,与没有电流阻挡层的发光二极管相比,生长1.5对SiO₂/TiO₂ DBR和Al镜作为电流阻挡层的发光二极管的光输出功率提高了12.5%,且光输出功率的分布更加均匀。     

数值分析渐变DBR对垂直腔面发射激光器谐振腔模的影响

通过数值分析研究了含线性渐变层的Al0.9Ga0.1As/AlyGa1-yAs/GaAs/AlxGa1-xAS DBR的光学特性及其对VCSEL谐振腔光学特性的影响,建立了渐变型DBR渐变层厚度与折射率的关系,通过特征矩阵法计算了突变GaAs/Al0.9Ga0.1AS DBR和渐变型DBR的反射谱和反射相移,分析了渐变层对DBR反射率和反射相移的影响.对渐变型DBR,要使VCSEL谐振腔满足中心波长相位匹配条件,还需要在DBR靠近谐振腔一侧的最前面增加一定厚度的渐变层,称为相位匹配层.通过计算,我们得到了使VCSEL谐振腔满足相位匹配条件时均匀层和相位匹配层的厚度.     

Surface-emitting laser diode with distributed Bragg reflector and buried heterostructure

A surface-emitting laser diode (SELD) with distributed Bragg reflector (DBR) and buried heterostructure (BH) is fabricated by the metalorganic chemical vapour deposition (MOCVD), reactive ion beam etching (RIBE) and liquid phase epitaxial (LPE) regrowth techniques. An Al/sub 0.1/Ga/sub 0.9/As/Al/sub 0.7/Ga/sub 0.3/As multilayer is employed for the lower reflector. The active region is embedded with Al/sub 0.4/Ga/sub 0.6/As current blocking layers. The threshold current is 28 mA, and the spectral width is 2.5 AA. A 2*2 array is also demonstrated.<>     

Thermal Stability Improvement of Vertical Conducting Green Resonant-Cavity Light-Emitting Diodes on Copper Substrates

Green light vertical-conducting resonant-cavity light-emitting diodes (RCLEDs) have been fabricated on a Cu substrate by the combination of laser lift-off and plating techniques. The structure of the RCLED/Cu is consisted of the InGaN-GaN multiple-quantum-well active layer between three layers of the dielectric TiO-SiO distributed Bragg reflector as a top mirror and an Al metal layer as a bottom mirror. It was found that the RCLED with Cu substrate presents superior thermal dissipation and a stable electroluminescence emission peak wavelength (507 nm) under a high injection current. It is attributed to the Cu substrate providing a good heat sink and effectively reducing the junction temperature.     

Coherent operation of monolithically integrated master oscillator amplifiers

Monolithically integrated master oscillator power amplifiers have been fabricated. The oscillator is a second order distributed Bragg reflector (DBR) laser. The epitaxial layer structure consists of a double quantum well active region bonded by Al/sub 0.3/Ga/sub 0.7/As confining layers and Al/sub 0.4/Ga/sub 0.6/As cladding layers. The resultant output is a single longitudinal mode in a nearly diffraction limited output to a power level of 485 mW.<>     

Room-temperature pulsed operation of AlGaAs/GaAs vertical-cavitysurface-emitting laser diode on Si substrate

Room-temperature pulsed AlGaAs/GaAs vertical-cavity surface-emitting laser diode (VCSELD) has been grown on Si substrate using metalorganic chemical vapor deposition. The VCSELD structure grown on Si substrate consists of a single quantum well active layer and a 20-pair of AlAs/GaAs distributed Bragg reflector (DBR). The measured reflectivity of the 20-pair of AlAs/GaAs DBR was 93% at the wavelength of 860 nm. The VCSELD on Si substrate exhibited a threshold current of 79 mA and a threshold current density of 4.9 kA/cm² under pulsed condition at room temperature     

Thermal stability of C-doped GaAs/AlAs DBR structures

Thermal stability of heavily carbon-doped and undoped DBRs has been investigated by reflectivity measurements and Raman spectroscopy. These analytical techniques are used to study the effect of heavy C-doping on Al–Ga interdiffusion during subsequent high-temperature anneals. Reflectivity spectra around the DBR stop-band wavelength clearly show that the growth-rate is reduced due to etching associated with the CBr₄ precursor used, but they also indicate that no Al–Ga interdiffusion that could significantly degrade the DBR performance takes place for any samples during annealing. The results are supported by Raman spectra, which indicate the positions of the LO and LOPC modes do not change when the DBRs are annealed, whether the DBRs are doped or not. Simulations of Al–Ga interdiffusion at GaAs/AlAs DBR interfaces indicates that intermixing up to ～15 nm on either side of each interface will not affect the reflectivity of the DBR stack significantly. The observed small changes in the stop-band central wavelength and peak reflectivity due to annealing is most likely a consequence of increased surface roughness resulted from annealing.     

Epitaxial (Al,Ga)InP-oxide distributed Bragg reflectors for use invisible-wavelength optical devices

Epitaxially-grown distributed Bragg reflectors (DBR's) employing thermally oxidized AlAs as the low refractive index constituent and (Al,Ga)InP as the high index constituent are fabricated. The 4.5-pair Ga _0.5In_0.5 P-oxide and Al_0.5In_0.5 P-oxide DBR's exhibit high reflectivity (>90%) over a range of 635-967 nm and 470-676 nm, respectively. The (Al,Ga)InP-oxide DBR's are shown to require less material to produce high reflectivity and to have significantly wider bandwidth than all-semiconductor DBR's used in the visible spectrum     

Room temperature pulsed operation of 1.5 μm GaInAsP/InPvertical-cavity surface-emitting laser

Room-temperature pulsed operation of a GaInAsP/InP vertical-cavity surface-emitting laser diode (VCSELD) with an emission wavelength near 1.55 μm is reported. A double heterostructure with a 34-pair GaInAsP (λ_g=1.4 μm)/InP distributed Bragg reflector (DBR) was grown by metalorganic chemical vapor deposition (MOCVD). The measured reflectivity of the semiconductor DBR is over 97% and threshold current is 260 mA for a 40-μmφ device with a 0.88-μm-thick active layer. Threshold current density is as low as 21 kA/cm² at room temperature     

A novel vertical-cavity surface-emitting laser with semiconductor/superlattice distributed bragg reflectors

Taking into account the tunneling effect of the superlattice, the authors present for the first time a vertical-cavity surface-emitting laser with AlAs[GaAs-AlAs] semiconductor/superlattice distributed Bragg reflectors (DBRs). The structure of a 19-period-AlAs (73.3 nm)-18.5-pair [GaAs (3.0 nm)-AlAs (0.7 nm)] DBR was grown on an n-GaAs [100] substrate by molecular beam epitaxy, and the device was fabricated by using a modified technique of proton implantation. It was found from the experiments that the peak reflectivity of the DBR is as high as 99.7%, the central wavelength is at about 840 nm, and the reflection bandwidth is wide up to 90 nm. A 20/spl times/20 /spl mu/m/sup 2/ square mesa on the top of the DBR was made by the wet chemical etching method to measure the series resistance of the devices. It can be seen that more than a third of them are within 20-30 /spl Omega/ that lead to ideal optical characteristics, low dissipated power, and reliability-some of the most important factors for the devices to be used in a number of applications in the future.