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1 前言 近年来GaAs—AlGaAs双异质结(DH)激光器的惊人进展,是与晶体液相外延生长技术的改善分不开的。对充分利用异质结光电特微的DH激光器来说,很明显界质结介面的质量对器件的各种特性都有很大的影响。我们认为致使GaAs—AlGaAs异质结质量下降的最重要因素是因为混入了氧。AlGaAs中随着AlAs百分比的增加就 相似文献
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本文叙述了用半导体激光器产生光脉冲的基本原理,介绍了用电脉冲驱动AlGaAs/GaAs双异质结激光器产生ps光脉冲的线路原理及实验结果。 相似文献
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本文讨论了GaAs/AlGaAs异质结界面的H线发光及其性能。用双晶X射线衍射及皮秒光致发光证明了H线与界面质量密切相关,并且有相似于激子跃迁的寿命行为。用限制于异质结界面势阱的二维电子(或空穴)与分布于GaAs边的三维空穴(或电子)组成的二维激子效应,解释了H线的实验结果。并讨论了不同外延生长的异质结与界面有关的发光行为。 相似文献
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为了提高器件的可靠性和使用寿命,设计并研制了一种将p-n结和有源层分开的高功率AlGaAs/GaAs单量子阱远异质结(SQW-RJH)激光器,发射波长为808nm,腔长900μm,条宽100μm,其外延结构与通常的808nm AlGaAs/GaAs单量子阱半导体激光器的结构不同,在p-n结和有源区间多了一层p型AlGaAs层,其厚度约为0.1μm。为减小衬底表面位错对外延层质量的影响,在n^ -GaAs衬底和n-Al0.5Ga0.5As下包层间加一层n^ -GaAs缓冲层。对器件进行了电导数测试及恒流电老化实验。与常规AlGaAs/GaAs大功率半导体激光器相比,远结大功率半导体激光器具有阈值电流Ith偏大、导通电压Vth偏高的直流特性。3000h的恒流电老化结果表明,器件在老化初期表现出阈值电流随老化时间缓慢下降,输出功率随老化时间缓慢上升的远结特性。 相似文献
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在GaAs基底上已做出GaAs—GaAlAs—GaAs—GaAlAs异质结构,它与corning7056玻璃粘结,基底GaAs以及在基底GaAs上面的AlGaAs用化学方法腐蚀掉,腐蚀GaAs与AlGaAs的腐蚀剂分别为NH_4OH—H_2O_2与HF溶液。GaAs—AlGaAs玻璃结构具有特别好的形态、厚度均匀和透射式光电发射性能好的特点。 相似文献
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利用金(Au)辅助催化的方法,通过金属有机化学气相沉积技术制备了GaAs纳米线及GaAs/InGaAs纳米线异质结构.通过对扫描电子显微镜(SEM)测试结果分析,发现温度会改变纳米线的生长机理,进而影响形貌特征.在GaAs纳米线的基础上制备了高质量的纳米线轴、径向异质结构,并对生长机理进行分析.SEM测试显示,GaAs/InGaAs异质结构呈现明显的“柱状”形貌与衬底垂直,InGaAs与GaAs段之间的界面清晰可见.通过X射线能谱对异质结样品进行了线分析,结果表明在GaAs/InGaAs轴向纳米线异质结构样品中,未发现明显的径向生长.从生长机理出发分析了在GaAs/InGaAs径向纳米线结构制备过程中伴随有少许轴向生长的现象. 相似文献
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《Physica E: Low-dimensional Systems and Nanostructures》2011,43(10):2722-2726
Heterostructure in the catalyst-free GaAs nanowire grown on the Si substrate was studied for the application of optical devices in the next generation. We fabricated AlGaAs/GaAs/AlGaAs quantum well (QW) structure on the side facet of the catalyst-free GaAs nanowire grown by molecular beam epitaxy (MBE). The cathode luminescence (CL) measurement showed that the uniform GaAs quantum well was formed between AlGaAs shell layers. On the basis of this structure, we also grew the thick AlGaAs shell layers (∼700 nm) on GaAs nanowires, and observed whispering gallery mode (WGM) resonant in the thick AlGaAs hexagonal structure. 相似文献
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A.A. Shakhmin M.V. Zamoryanskaya I.N. Arsentyev S.G. Konnikov D.A. Vinokurov A.L. Stankevich I.S. Tarasov 《Superlattices and Microstructures》2009,45(4-5):376-382
The article shows the cathodoluminescence technique application to a quality analysis of a semiconductor multilayer heterostructures. Two structures with a GaAs quantum well embedded between the AlGaAs and GaInP barriers were investigated. The AlGaAs/GaAs/GaInP and GaInP/GaAs/AlGaAs structures were grown by MOCVD on a GaAs substrate. In this work we study the interface quality of quantum-dimensional GaAs layer by means of the local cathodoluminescence. Degradation and broadening of GaAs/GaInP interface occurring during the growth process of GaAs on GaInP layer was assumed to result in the formation of a layer with mixed composition at the interface. In addition, the presence of the layer prevented the formation of a quantum well in the GaAs layer. The transition layer was clearly observed by the cathodoluminescence. In the other case it was found that the growth of a structure with GaAs layer on top of AlGaAs produced a quantum well with a 10 nm thickness. The interface quality and layer thicknesses were also confirmed by the X-ray diffraction investigation of these structures. 相似文献
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《Current Applied Physics》2019,19(6):756-761
An externally applied magnetic field was used to induce increased photocarrier transport along the high mobility channel in GaAs/AlGaAs modulation-doped heterostructures (MDH). The terahertz (THz) emission from GaAs/AlGaAs MDH increases with increasing magnetic field, applied parallel to the heterojunction. The THz emission enhancement factors due to the magnetic field in MDH are higher than in undoped GaAs/AlGaAs heterojunction and in bulk SI-GaAs. This demonstrates that properly utilizing the high-mobility channel for carrier transport promises to be a viable design consideration for efficient THz photoconductive antenna (PCA) devices. Moreover, it was observed that for MDH, as well as for an undoped GaAs/AlGaAs heterojunction, the enhancement for one magnetic field direction is greater than the enhancement for the opposite direction. This is in contrast to the symmetric enhancement with magnetic field direction observed in a bulk SI-GaAs. An analysis of photocarrier trajectories under an external magnetic field supports the explanation that the enhancement asymmetry with magnetic field direction in MDH is due to the cycloid motion of electrons as affected by the GaAs/AlGaAs interface. 相似文献
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《Superlattices and Microstructures》1998,23(2):265-271
We present a study of GaInP/GaAs interfaces by means of photoluminescence (PL) of multi quantum wells (MQW), embedded in GaInP, or asymmetric structures having an AlGaAs barrier GaInP/GaAs/AlGaAs. The PL energies of quantum wells were compared with calculations based on the transfer matrix envelope function approximation, well suited for asymmetric structures. GaInP/GaAs/AlGaAs MQW structures (GaInP grown first) are in reasonably good agreement with calculations. Reverse ones, AlGaAs/GaAs/GaInP, present a lower PL energy than calculated. But the agreement with theory is recovered on single quantum well samples, or in MQW when the GaInP thickness is increased up to 100 nm. We interpret this phenomenon as a diffusion of arsenic atoms from the next GaAs well through the GaInP barrier. Arsenic atoms exchange with phosphorus atoms at the GaInP-on-GaAs interface of the former well, leading to a small gap strained InGaAs region responsible for the lowering of PL energies. 相似文献
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A. Rastelli R. Songmuang O. G. Schmidt 《Physica E: Low-dimensional Systems and Nanostructures》2004,23(3-4):384
We report on a new method to produce self-assembled, unstrained, GaAs/AlGaAs quantum dots (QDs) with large confinement energy. First we create nanoholes on a GaAs surface by growing InAs islands on GaAs(0 0 1), overgrowing them with GaAs and etching the surface in situ with AsBr3 gas. Then we transfer the holes to an AlGaAs surface, fill them with GaAs and overgrow them with AlGaAs. In this way we obtain GaAs inclusions in an AlGaAs matrix. We investigate the optical properties of such QDs by photoluminescence spectroscopy and their morphology by atomic force microscopy. We show that the QD size can be tuned and emission with inhomogeneous broadening down to 8.9 meV can be achieved. 相似文献
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G. K. Rasulova P. N. Brunkov I. V. Pentin V. V. Kovalyuk K. N. Gorshkov A. Yu. Kazakov S. Yu. Ivanov A. Yu. Egorov D. A. Sakseev S. G. Konnikov 《Technical Physics》2011,56(6):826-830
The interaction of self-oscillators based on 30-period weakly coupled GaAs/AlGaAs superlattices is studied. The action of
one self-oscillator on the other was observed for a constant bias voltage in the absence of generation of self-sustained oscillations
in one of the oscillators. It is shown that induced oscillations in a forced oscillator appear due to excitation of oscillations
in the system of coupled oscillators forming the electric-field domain wall at the frequency of one of the higher harmonics
of a forcing oscillation. 相似文献
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Comparison of two kinds of active layers for high-power narrow-stripe distributed feedback laser diodes
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Usually GaAs/AlGaAs is utilized
as an active layer material in laser diodes operating
in the spectral range of 800--850 nm. In this work, in addition to a
traditional unstrained GaAs/AlGaAs distributed feedback (DFB) laser diode,
a compressively strained InGaAlAs/AlGaAs DFB laser
diode is numerically investigated in characteristic. The simulation results show that the
compressively strained DFB laser diode has a lower transparency carrier
density, higher gain, lower Auger recombination rate, and higher stimulated
recombination rate, which lead to better a device performance, than
the traditional unstrained GaAs/AlGaAs DFB laser diode. 相似文献
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T. P. Martin R. P. Taylor H. Linke C. A. Marlow G. D. R. Hall I. Shorubalko I. Maximov W. Seifert L. Samuelson T. M. Fromhold 《Superlattices and Microstructures》2003,34(3-6):179
We present measurements of the potential profile of etched GaInAs/InP billiards and show that their energy gradients are an order of magnitude steeper than those of surface-gated GaAs/AlGaAs billiards. Previously observed in GaAs/AlGaAs billiards, fractal conductance fluctuations are predicted to be critically sensitive to the billiard profile. Here we show that, despite the increase in energy gradient, the fractal conductance fluctuations persist in the harder GaInAs/InP billiards. 相似文献