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1.
采用气态源分子束外延(GSMBE)技术优化生长了GaAs/AlAs分布布拉格反射镜(DBR)材料,并用X射线衍射(XRD)及反射光谱对其生长质量进行了表征。结果表明,采用5S间断生长的GaAs/AlAs DBR材料质量和界面质量优于无间断生长,并且10对GaAs/AlAs DBR的质量优于30对,说明DBR对数越多,周期厚度波动越大,材料质量越差。优化生长得到的30对GaAs/AlAsDBR的反射率大于99%,中心波长为1316nm,与理论设计结构的模拟结果基本一致,可用作1.3μm垂直腔面发射激光器(VVSEL)直接键合的反射腔镜。 相似文献
2.
GasSourceMolecularBeamEpitaxyGrowthofSi1-xGex/SiAloysLiuXuefeng,LiJianpingandSunDianzhao(刘学锋)(李建平)(孙殿照)MaterialScienceCenter... 相似文献
3.
A. Y. Lew C. H. Yan R. B. Welstand J. T. Zhu C. W. Tu P. K. L. Yu E. T. Yu 《Journal of Electronic Materials》1997,26(2):64-69
We have used cross-sectional scanning tunneling microscopy (STM) to study interface structure in arsenide/phosphide heterostructures grown by gas-source molecular beam epitaxy (GSMBE) and by low-pressure metalorganic vapor phase epitaxy (LP-MOVPE). High-resolution images of GSMBE samples consisting of GaAs interrupted at 200Å intervals with a 40 s P2 flux reveal substantial, growth-temperature-dependent incorporation of phosphorus with nanometer-scale lateral variations in interface structure. STM images of InGaAs/InP multiple quantum well structures grown by LP-MOVPE show evidence of interface asymmetry and extensive atomic cross-incorporation at the interfaces. Data obtained by STM have been corroborated by high-resolution x-ray diffraction and reflection high-energy electron diffraction. Together, these studies provide direct information about nanometer-scale grading and lateral nonuniformity of arsenide/phosphide interfaces that can occur under these growth conditions. 相似文献
4.
L. M. Woods P. Silvestre P. Thiagarajan G. A. Patrizi G. Y. Robinson K. M. Jones M. Al-Jassim 《Journal of Electronic Materials》1994,23(11):1229-1233
Quantum well (QW) structures consisting of InGaAsP wells and InGaAsP barriers grown by gas-source molecular beam epitaxy have
been examined by low temperature photoluminescence (PL) in order to evaluate the contributions of compositional fluctuations
in the quaternary alloy and of interface roughness to the PL linewidth. The well material was InGaAsP with a bandgap corresponding
to a wavelength of 1.3 μm and the barrier material was InGaAsP of 1.15 μm. The theory for QW excitonic linewidths as a function
of well thickness Lz due to fluctuations in alloy composition has been extended to include the case of the quaternary InGaAsP barrier. If the
interfaces are atomically abrupt, the linewidth is dominated by compositional fluctuations in the well at large Lz and compositional fluctuations in the barrier at small Lz. The theory predicts a weak dependence of the linewidth on Lz since the composition of the well and barrier are similar. For rough heterointerfaces, the theory indicates the usual increase
in linewidth with decreasing Lz. Photoluminescence measurements at 13K in arrays of single InGaAsP/InGaAsP QWs with Lz from 1.0 to 6.0 nm show only a weak variation of the full width at half maximum (FWHM) with Lz, in agreement with the theory for smooth interfaces. Furthermore, the lowest measured FWHM of 8.9 meV was found for a narrow
well of Lz=1.8 nm, indicating the InGaAsP/InGaAsP interfaces are smooth and that the PL linewidth is dominated by compositional fluctuations. 相似文献
5.
采用 GSMBE技术 ,在材料表征和分析的基础上 ,通过优化生长条件 ,生长出高性能In0 .4 9Ga0 .51P/ Ga As异质结双极晶体管 (HBT)微结构材料 ,并制备出器件。材料结构中采用了厚度为 6 0 nm、掺杂浓度为 3× 10 19cm-3的掺 Be Ga As基区和 5nm非掺杂隔离层 ,器件流片中采用湿法化学腐蚀制作台面结构。测试结果表明该类器件具有良好的结特性 ,在集电极电流密度 2 80 A/cm2时其共发射极电流增益达 32 0。由此说明非掺杂隔离层的引入有效地抑制了由于基区 Be扩散导致的 pn结与异质结偏位及其所引起的器件性能劣化。 相似文献
6.
采用气态源分子束外延方法及应用有源区同质结构及较薄的组分渐变InxGa1-xAs缓冲层,研制了波长扩展的InGaAs/InP光伏探测器系列,其室温下的截止波长分别约为1.9μm,2.2μm.和2.5μm.对此探测器系列在较宽温度范围内的性能进行了细致表征,结果表明在室温下其R0A乘积分别为765,10.3和12.7Ωcm2,比室温降低100K时其暗电流和R0A可改善约3个量级.瞬态特性测量表明此探测器系列适合高速工作,实测响应速度已达数十ps量级. 相似文献
7.
H. C. Kuo J. M. Kuo Y. C. Wang C. H. Lin H. Chen G. E. Stillman 《Journal of Electronic Materials》1997,26(8):944-948
We report the determination of band offset ratios, using photoluminescence excitation measurements, for GaInP/GaAs and AlInP/GaAs
quantum wells grown by gas-source molecular beam epitaxy. To reduce the uncertainty related to the intermixing layer at heterointerfaces,
the residual group-V source evacuation time was optimized for abrupt GalnP/GaAs (AlInP/GaAs) interfaces. Based upon thickness
and composition values determined by double-crystal x-ray diffraction simulation and cross-sectional transmission electron
microscopy, the transition energies of GalnP/GaAs and AlInP/GaAs quantum wells were calculated using a three-band Kane model
with varying band-offset ratios. The best fit of measured data to calculated transition energies suggests that the valence-band
offset ratio (γ band discontinuity) was 0.63 ± 0.05 for GalnP/GaAs and 0.54 ± 0.05 for AlInP/GaAs heterostructures. This result
showed good agreement with photoluminescence data, indicating that the value is independent of temperature. 相似文献
8.
The P-As exchange reaction on InP surface exposed to As4 beam was studied using photoluminescence (PL) and x-ray diffraction measurements as well as ultra-high vacuum scanning tunneling
microscopy observation. It was found that as high as 90–95% of P can be exchanged by As and that the average depth of exchange
reaction increases with the increase of As exposure time, being as deep as 5.5 ML for a long exposure. The splitting of PL
peak takes place when the reaction depth exceeds 2 ML and the number of the split subpeaks increases with the increase of
As exposure time. The PL peak splitting originates from the fluctuation of well thickness, caused by formation of InAs islands
for strain relief during the exchange reaction. 相似文献
9.
GSMBE InGaP/GaAs材料大面积均匀性研究 总被引:2,自引:0,他引:2
报道了气态源分子束外延 (GSMBE)技术生长的Φ5 0mm ,Φ75mmInGaP/GaAs材料的晶体完整性 ,组分均匀性和表面缺陷密度。用PhilipsX Pert′s四晶衍射仪沿Φ5 0mm ,Φ75mmInGaP/GaAs样品的x轴和y轴以 5mm间隔测量ω/2θ双晶摇摆曲线 ,获得沿x轴和y轴方向的晶格失配度分布和组分涨落分布。结果表明 ,用GSMBE生长的Φ5 0mm和Φ75mmIn0 .4 9Ga0 .51 P与GaAs衬底的失配度分别为 1× 10 - 4和 1× 10 - 5,组分波动Φ5 0mm沿x轴和y轴分别为± 0 .1%和± 0 .2 % ,Φ75mm <± 1%。表面缺陷密度在 1× 10~ 1× 10 2 cm- 2 。 相似文献
10.