Strained AlGaInAs/AlGaAs quantum wells and quantum-well lasersgrown by molecular beam epitaxy

Suitable growth conditions for strained AlGaInAs grown on GaAs substrates by molecular beam epitaxy (MBE) are presented, and strained layer multiple quantum well AlGaInAs lasers grown by MBE are demonstrated. Low-temperature photoluminescence was used to characterize quantum wells grown at different temperatures with different Al, Ga, and In compositions to establish growth parameters     

高饱和电流14xx nm应变量子阱激光器的研制

报道了14xx nm应变量子阱(SQW)激光器管芯的研制成果。通过金属有机化学气相沉积(MOCVD)生长工艺生长14xx nm AlGaInAs/AlInAs/InP应变量子阱外延片,采用带有锥形增益区的脊型波导结构制作激光器管芯。生长好的外延片按照双沟脊型波导激光器制备工艺进行光刻、腐蚀,制作P面电极(溅射 TiPtAu)、减薄、制作N面电极(蒸发AuGeNi),然后将试验片解理成Bar;为获得高的单面输出功率,用电子回旋共振等离子体化学气相沉积(ECR)进行腔面镀膜,HR=90%,AR=5%;解理成的管芯P面朝下烧结到铜热沉上,TO3封装后在激光器综合测试仪进行测试。管芯功率达到440 mW以上,饱和电流3 A以上,峰值波长1430 nm,远场发散角为40°×14°。     

Strained 1.3 μm MQW AlGaInAs lasers grown by digital alloy MBE

AlGaInAs strained MQW lasers, emitting at 1.3 μm, have been prepared for the first time using a digital alloy approach. 2 μm stripe geometry lasers have characteristics comparable to those of lasers prepared using bulk alloy layers. The infinite length threshold current densities are as low as 140 kA/cm²/quantum well and T ₀ values (20-40°C) range from 75-90 K for chip lengths of 375-2375 μm     

1.3-μm InAsP modulation-doped MQW lasers

The effect of both n-type and p-type modulation doping on multiple-quantum-well (MQW) laser performances was studied using gas-source molecular beam epitaxy (MBE) with the object of the further improvement of long-wavelength strained MQW lasers. The obtained threshold current density was as low as 250 A/cm² for 1200-μm-long devices in n-type modulation-doped MQW (MD-MQW) lasers. A very low CW threshold current of 0.9 mA was obtained in 1.3-μm InAsP n-type MD-MQW lasers at room temperature, which is the lowest ever reported for long-wavelength lasers using n-type modulation doping, and the lowest value for lasers grown by all kinds of MBE in the long-wavelength region. Both a reduction of the threshold current and the carrier lifetime in n-type MD MQW lasers caused the reduction of the turn-on delay time by about 30%. The 1.3-μm InAsP strained MQW lasers using n-type modulation doping with very low power consumption and small turn-on delay time are very attractive for laser array applications in high-density parallel optical interconnection systems. On the other hand, the differential gain was confirmed to increase by a factor of 1.34 for p-type MD MQW lasers (N_A=5×10¹⁸ cm ^-3) as compared with undoped MQW lasers, and the turn-on delay time was reduced by about 20% as compared with undoped MQW lasers. These results indicate that p-type modulation doping is suitable for high-speed lasers     

Strained InGaAs quantum well lasers grown on

The growth by molecular beam epitaxy (MBE) of AlGaAs/GaAs/InGaAs strained quantum well lasers on GaAs     

Performance improvement of circular-grating surface-emitting DBRlasers using an MQW structure with etch-stop layer

The authors demonstrate low threshold current high efficiency operation of circular-grating surface-emitting distributed Bragg reflector (CG-SE-DBR) lasers. A strained InGaAs-GaAs triple quantum well with an etch-stop layer was grown by MBE. Circular gratings are defined by electron beam lithography. A threshold current as low as 17 mA and a pulsed output power >170 mW at ~980 nm wavelength are obtained     

MBE生长InGaAs／GaAs应变层单量子阱激光器结构材料的研究

采用ＶａｒｉａｎＧｅｎⅡＭＢＥ生长系统研究了ＩｎＧａＡｓ／ＧａＡｓ应变层单量子阶（ＳＳＱＷ）激光器结构材料。通过ＭＢＥ生长实验，探索了Ｉｎ＿ｘＧａ＿（１－ｘ）ｔＡｓ／ＧａＡｓＳＳＱＷ激光器发射波长（λ）与Ｉｎ组分（ｘ）和阱宽（Ｌ＿ｚ）的关系，并与理论计算作了比较，两者符合得很好。还研究了材料生长参数对器件性能的影响，主要包括：Ⅴ／Ⅲ束流比，量子阱结构的生长温度Ｔ＿ｇ（ＱＷ），生长速率和掺杂浓度对激光器波长、阈值电流密度、微分量子效率和器件串联电阻的影响。以此为基础，通过优化器件结构和ＭＢＥ生长条件，获得了性能优异的Ｉｎ＿（０．２）Ｇａ＿（０．８）Ａｓ／ＧａＡｓ应变层单量子阱激光器：其次长为９６３ｎｍ，阈值电流密度为１３５Ａ／ｃｍ￣２，微分量子效率为３５．１％。     

MBE-grown Ridge-waveguide InGaAs/InGaAsP Strained Quantum Well Lasers at 2 μm Wavelength

The result of molecular beam epitaxy (MBE)-grown ridge-waveguide InGaAs/ InGaAsP/InP strained quantum well lasers at 2 μm wavelength is reported. The pulsed electrical luminescence spectrum at room temperature is observed with peak wavelength of about 1.98 μm. At 77 K the lasers become lasing in pulse regime, with threshold current of about 18～30 mA, peak wavelength of about 1.87～ 1. 91 μm, and single longitudinal mode operation in the current range of 160～230 mA.     

(InAs)/sub 1//(GaAs)/sub 4/ superlattice strained quantum well laser at 980 nm

The first successful MBE growth of (InAs)/sub 1//(GaAs)/sub 4/ short-period superlattice (SPS) strained quantum well lasers emitting at approximately 980 nm is reported. The SPS consists of six periods of one and four monolayers of InAs and GaAs, respectively. The measured threshold current density was approximately 100 A cm/sup -2/ for 0.96 mm long lasers. Devices have operated up to 170 degrees C with a characteristic temperature T/sub 0/ of 148 K. The (InAs)/sub m//(GaAs)/sub n/ superlattice is an ordered counterpart of the InGaAs random alloy, and provides an alternative method fabricating high speed electronic and photonic devices.<>     

刻蚀端面AlGaInAs/AlInAs激光器的制作与特性

利用Cl2／BCl3／CH4电感应耦合等离子体（ICP）干法刻蚀技术，实现了对AlGaInAs，InP材料的非选择性刻蚀。AlGaInAs与InP的刻蚀速率分别为820nm／min与770nm／min，获得了刻蚀深度为4．9μm，垂直光滑的AlGaInAs／AlInAs激光器的刻蚀端面。在此基础上制作出宽接触的刎蚀端面AlGaInAs／AlInAs激光器，实现了室温脉冲激射，其阈值电流和微分量子效率与传统的解理端面激光器基本相当。并通过刻蚀端面与解理端面激光器特性的比较（包括电流-电压、电流输出光功率以及远场特性），分析了刻蚀端面的引入对激光器特性的影响。     

高功率14xxnm半导体激光器

高功率14xxnm半导体激光器是光纤Raman放大器的理想泵浦源,它能够提供大功率、宽带输出,而且其动态可调谐,频率稳定性好,成本低。本文详细介绍了高功率14xxnm半导体激光器的材料生长、器件结构和封装工艺,总结了AlGaInAs材料生长的难点和结构方面的改进措施,指出了带有锥形增益区的脊形波导结构是获取高功率、良好远场单模特性的有效途径。本文还报导了国内外高功率14xxnm半导体激光器的最新产品性能和研发状况,指出了国内进一步研制高功率14xxnm激光器的研究难点和重点。     

Monolithic integration on InP of a Wannier Stark modulator with astrained MQW DFB 1.55-μm laser

We present the technical approach and the preliminary device results on the first integration of a Wannier Stark (WS) electroabsorption (EA) modulator with a DFB laser on InP. The WS modulator active layer consists of a lattice matched InGaAs-InAlAs superlattice (SL) grown by solid source MBE. It is butt-coupled to a laser grown by AP-MOVPE whose active layer includes a strained InGaAsP-InGaAsP MQW stack. Device results cover static performances of integrated lasers and modulators, and measurements of high frequency characteristics (small signal bandwidth and 10 Gb/s eye diagram)     

MOVPE生长1.3 μm无致冷AlGaInAs/InP应变补偿量子阱激光器研究

通过低压金属有机化学气相外延 (LP MOVPE)工艺生长了AlGaInAs应变补偿量子阱材料 ,通过X射线双晶衍射、光荧光、二次离子质谱的测试分析得到了材料生长的优化工艺参数 ,降低了材料中的氧杂质含量 ,得到了高质量AlGaInAs应变补偿量子阱材料 ,室温光致发光半宽FWHM =2 6meV。采用此外延材料成功制作了 1 3μm无致冷AlGaInAs应变量子阱激光器 ,器件测试结果为 :激射波长 :12 90nm≤ λ≤ 1330nm ;阈值电流 :Ith(2 5℃ )≤15mA ;Ith(85℃ )≤ 2 5mA ;量子效率变化 :Δηex(2 5～ 85℃ )≤ 1 0dB。     

1.3-/spl mu/m Vertical-cavity surface-emitting lasers with double-bonded GaAs-AlAs Bragg mirrors

We demonstrate, for the first time, double-bonded AlGaInAs strain-compensated quantum-well 1.3-/spl mu/m vertical-cavity surface-emitting lasers (VCSELs). GaAs-AlAs Bragg mirrors were wafer-bonded on both sides of a cavity containing the AlGaInAs strain-compensated multiple-quantum-well active layers sandwiched by two InP layers. The lasers have operated under pulsed conditions at room temperature. A record low pulsed threshold current density of 4.2 kA/cm/sup 2/ and a highest maximum light output power greater than 4.6 mW have been achieved. The maximum threshold current characteristic temperature T/sub 0/ of 132 K is the best for any long wavelength VCSELs. The laser operated in a single-longitudinal mode, with a side-mode suppression ratio of more than 40 dB, which is the best results for 1.3-/spl mu/m VCSELs.     

Design and performance of a vertical cavity surface emitting laserbased on III-V quaternary semiconductor alloys for operation at 1.55μm

A highly efficient Vertical Cavity Surface Emitting Laser (VCSEL) has been designed and fabricated for operation at a wavelength of 1.546 μm. The device design incorporates optimized Bragg mirrors with minimized number of periods. The present structure employs quaternary III-V semiconductor alloys with GaInAsP as the active layer and AlGaInAs/InP multilayer stack as the Distributed Bragg Reflector (DBR). The material parameters of the quaternary alloys including index of refraction and bandgap energy are calculated over the entire composition range. The difference in the indices of refraction between AlGaInAs and InP alternating layers is found to be 0.46 resulting in a significant reduction of the number of DBR layers. The MBE technique is employed for the epitaxial VCSEL structure growth and the selective oxidation of AlInAsP single layer is used to form the current confinement aperture. The VCSEL gain performance has been calculated and measured, resulting in the experimental threshold current of about 3 mA and the output power of 1 mW     

Wafer fusion of infrared laser diodes to GaN light-emittingheterostructures

In this letter, we use wafer fusion to integrate AlGaInAs quantum-well (QW) laser heterostructures to GaN laser diode and light-emitting diode (LED) structures. After fusion of the laser heterostructure to the GaN layers, AlGaInAs QW lasers are fabricated and characterized. Lasers of 15×510 μm operate with a threshold of 20 mA and external differential quantum efficiency of 15.5%/facet at a wavelength of 820 nm, InGaN-GaN LED's, fabricated 75 μm from the lasers, emit at 458 nm. The operation of the lasers and LED's fused to GaN demonstrates that the fused interface is mechanically robust, and the properties of fused heterostructures are not adversely affected by the fusion process     

10Gbit/s高T0无制冷分布反馈激光器

与折射率耦合分布的分布反馈（DFB）激光器相比,不管界面反射率是多少,增益耦合DFB激光器都能稳定地单纵模工作,而且具有高速、低啁啾的特性．本课题组用AlGaInAs/InP材料,采用增益耦合DFB结构,进行了单纵模激光器研发,并对器件特性进行了测试分析．     

高功率、高效率线阵半导体激光器的阳极氧化制备方法

在分子束外延(MBE)生长的基础上,采用脉冲阳极氧化工艺制作了非对称、宽波导InGaAlAs/AlGaAs/GaAs应变双量子阱(DQW)结构准连续(QCW)线阵半导体激光器,实现了808 nm波段线阵激光器的高效率、高功率运转。脉冲阳极氧化工艺主要用于器件工艺中的蚀刻与绝缘膜制备,电解液采用乙二醇∶去离子水∶磷酸∶2%盐酸的体积比为40∶20∶1∶1的混合溶液。研制的准连续线阵半导体激光器的填充因子约为72.7%,100 Hz,200μs准连续工作条件下的阈值电流约为24 A,斜率效率达到1.25 W/A,最大电-光转换效率达到51%。     

Growth and characterization of continuously graded index separateconfinement heterostructure (GRIN-SCH) InGaAs-InP long wavelengthstrained layer quantum-well lasers by metalorganic vapor phase epitaxy

A report is presented on the growth and characterization of the first InGaAs-InP-based graded-index separate-confinement-heterostructure (GRIN-SCH) strained quantum-well lasers operating near 1.47 μm. The structure features linearly graded InGaAsP waveguide layers for both optical and carrier confinement in a very narrow, strained quantum-well layers. The excellent structural quality of the active and waveguide regions has been confirmed by transmission electron microscopy (TEM) and secondary ion mass spectroscopy (SIMS) analysis results. Strained quantum-well lasers with well widths as narrow as 5-6 nm were fabricated with threshold current densities as low as 750 A/cm². Buried-heterostructure lasers based on strained quantum-well active lasers exhibit threshold currents as low as 10-15 mA with quantum efficiency of 70-80%. With antireflection coating on one side of the sample, the laser shows threshold current of 35 mA with highest output power of 160 mW     

GaInAs/AlGaInAs DH and MQW lasers with 1.5-1.7 mu m lasing wavelengths grown by atmospheric pressure MOVPE

The first successful growth and fabrication of long wavelength (1.5-1.7 mu m) DH and MQW lasers by atmospheric pressure MOVPE in a 'phosphorus-free' material system is reported. The GaInAs/AlGaInAs DH and MQW lasers were grown on InP substrates. DH lasers emitting at around 1690 nm exhibit threshold current densities down to 2.8 kA/cm/sup 2/ at 25 degrees C; the characteristic temperature is 50 K in the 15-55 degrees C range. First MQW lasers with 1565 nm emission wavelength have threshold current densities around 3.2 kA/cm/sup 2/.<>