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研制了双面键合长波长垂直腔面发射激光器(VCSEL),有效克服了传统外延生长方法存在的诸多难题通过对布拉格反射镜、有源区和光学腔的设计,结合键合技术进行工艺设计,于国内首次研制出双面键合长波长VCSEL,并分别采用光泵浦和电泵浦对其进行了测试与分析,测试结果表明结构及工艺设计是合理的,两次键合后的界面可以承受腐蚀、剥离、氧化等后工艺,且键合界面光、电性能良好,未对激光器性质造成明显的不良影响,器件激射波长约为1 273.6 nm,脉冲条件下表现出动态单纵模特性,在仪器测试范围内,20 μm尺寸的器件常温连续工作条件下的最大输出功率为0.16 mW.但P-I曲线的扭折说明器件仍旧存在着较大的热、电阻,需在后续的材料生长及键合技术中进一步优化. 相似文献
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系统阐述了金属键合的发展概况、基本工艺和方法、表征技术及其在光电器件中的应用.金属键合制备光电器件的一般工艺流程分为三步:蒸镀金属薄膜、键合、腐蚀去除衬底,列举了常用的金属键合方法及其工艺条件;并着重论述了该技术在光电器件特别是垂直腔面发射激光器(VCSEL)器件结构制作中的应用.金属键合可以实现衬底倒扣和改善器件热学性能,而对器件原有的光学性质影响不大. 相似文献
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为了降低光抽运外腔面发射激光器的热效应,提高激光器的输出功率,采用液体毛细键合方法将逆序生长的半导体外延片与高热导率的碳化硅散热窗口键合,并用化学刻蚀方法去除外延片的基质。实验研究了用基质刻蚀的外延片搭建的外腔面发射激光器的性能。当增益介质的有源区为InGaAs/AlGaAs多量子阱、抽运源为808nm的光纤耦合输出半导体激光器,输出镜对激光波长透过率为3%时,在室温下获得TEM00模的最大输出功率0.52W,激光波长1018nm,光谱线宽2nm(半峰全宽),激光器的光光转换效率约为20%。测得x方向与y方向的M2因子分别为1.01和1.00,说明输出光束为质量优良的近衍射极限高斯光束。结果表明,基质刻蚀技术可明显改善外腔面发射激光器的热性能,获得高功率、高光束质量的激光输出。 相似文献
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E. Bourdin S. Curran A. Davey W. Blau G. Blchl R. Becker H. Brunling 《Advanced functional materials》1994,4(1):43-49
Polydiheteroarylenemethines show a relatively high electrical conductivity. Two-coplanar-electrode measurements give a high surface conductivity of 10?9 S/□ and a high mobility up to 1 cm2 V?1. Depending on the type of side group, doping with iodine served to raise the conductivity by five orders of magnitude. Optical absorption analysed with DC and AC conductivity data revealed two components in the transport process: A VHR (variable range hopping) process shifting to a band tail polaronic process as the degree of polymerisation increases, corresponding to a very characteristic transition in the AC conductivity. The hopping process corresponds to an AC conductivity frequency power law dependence of ω0.66, whereas the polaronic process corresponds to a power law dependence of ω0.1. 相似文献
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本文通过对工艺条件的控制,获得了铜系混合导体材料Cu2Mo6S7、7、Cu2Mo6S8.0及Cu4Mo6S8.0.x射线衍射物相分析表明为Mo6S8结构的单相,并采用分析化学方法对其化学计量进行了分析,通过测试得到了三种混合导体的总电导率σ和离子电导率σi·当混合导体Cu2M06S7、7与固体电解质Rb4Cu16I7Cl13复合后可改善其电化学性能,复合比为2:1时,总电导率σ和离子电导率σi可达75(Ω·cm)-1和7×l0-2(Ω·cm)-1。 相似文献
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Strongly Anisotropic Thermal Conductivity of Free‐Standing Reduced Graphene Oxide Films Annealed at High Temperature 下载免费PDF全文
Jackie D. Renteria Sylvester Ramirez Hoda Malekpour Beatriz Alonso Alba Centeno Amaia Zurutuza Alexandr I. Cocemasov Denis L. Nika Alexander A. Balandin 《Advanced functional materials》2015,25(29):4664-4672
Thermal conductivity of free‐standing reduced graphene oxide films subjected to a high‐temperature treatment of up to 1000 °C is investigated. It is found that the high‐temperature annealing dramatically increases the in‐plane thermal conductivity, K, of the films from ≈3 to ≈61 W m?1 K?1 at room temperature. The cross‐plane thermal conductivity, K⊥, reveals an interesting opposite trend of decreasing to a very small value of ≈0.09 W m?1 K?1 in the reduced graphene oxide films annealed at 1000 °C. The obtained films demonstrate an exceptionally strong anisotropy of the thermal conductivity, K/K⊥ ≈ 675, which is substantially larger even than in the high‐quality graphite. The electrical resistivity of the annealed films reduces to 1–19 Ω □?1. The observed modifications of the in‐plane and cross‐plane thermal conductivity components resulting in an unusual K/K⊥ anisotropy are explained theoretically. The theoretical analysis suggests that K can reach as high as ≈500 W m?1 K?1 with the increase in the sp2 domain size and further reduction of the oxygen content. The strongly anisotropic heat conduction properties of these films can be useful for applications in thermal management. 相似文献
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S. Stefanoski L. N. Reshetova A. V. Shevelkov G. S. Nolas 《Journal of Electronic Materials》2009,38(7):985-989
We report on temperature-dependent thermal conductivity, resistivity, and Seebeck coefficient of two polycrystalline Br-containing
Sn-clathrate compounds with the type I crystal structure. Interstitial Br atoms reside inside the polyhedral cavities formed
by the framework, resulting in hole conduction. The framework bonding directly influences the transport properties of these
two compositions. The transport properties of these two clathrates are compared with those of other Sn-clathrates. We also
discuss our results in terms of the potential for thermoelectric applications. 相似文献
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Ramesh Chandra Mallik Christian Stiewe Gabriele Karpinski Ralf Hassdorf Eckhard Müller 《Journal of Electronic Materials》2009,38(7):1337-1343
The properties of Co4Sb12 with various In additions were studied. X-ray diffraction revealed the presence of the pure δ-phase of In0.16Co4Sb12, whereas impurity phases (γ-CoSb2 and InSb) appeared for x = 0.25, 0.40, 0.80, and 1.20. The homogeneity and morphology of the samples were observed by Seebeck microprobe and scanning
electron microscopy, respectively. All the quenched ingots from which the studied samples were cut were inhomogeneous in the
axial direction. The temperature dependence of the Seebeck coefficient (S), electrical conductivity (σ), and thermal conductivity (κ) was measured from room temperature up to 673 K. The Seebeck coefficient of all In-added Co4Sb12 materials was negative. When the filler concentration increases, the Seebeck coefficient decreases. The samples with In additions
above the filling limit (x = 0.22) show an even lower Seebeck coefficient due to the formation of secondary phases: InSb and CoSb2. The temperature variation of the electrical conductivity is semiconductor-like. The thermal conductivity of all the samples
decreases with temperature. The central region of the In0.4Co4Sb12 ingot shows the lowest thermal conductivity, probably due to the combined effect of (a) rattling due to maximum filling and
(b) the presence of a small amount of fine-dispersed secondary phases at the grain boundaries. Thus, regardless of the non-single-phase
morphology, a promising ZT (S
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σT/κ) value of 0.96 at 673 K has been obtained with an In addition above the filling limit. 相似文献
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该文从层压工序的设备、物料、生产管理等三个方面对层压板工序的产能进行了分析,就如何充分利用现有层压设备、控制好压板物料、做好生产管理来维持及提升层压工序的产能做了较详细的阐述。 相似文献