Te掺杂超宽带隙隧穿结研究

研究制备得到峰值电流密度为65.3A/cm2的GaInP/AlGaAs宽带隙隧穿结和峰值电流密度为6.1A/cm2的AlGaInP/AlGaAs超宽带隙隧穿结。在隧穿结中使用二乙基碲（DETe）作为n型掺杂剂,实验中研究了材料生长温度、阀门开关处理以及DETe的流量等生长参数。采用预掺杂和升温后处理的方式来解决碲源的开关效应,而Te掺杂引入的晶格失配采用应力平衡技术来消除。另外研究了不同DETe流量下制备得到的隧穿结性能。     

Interface Reaction Between Electroless Ni–Sn–P Metallization and Lead-Free Sn–3.5Ag Solder with Suppressed Ni3P Formation

The voids formed in the Ni₃P layer during reaction between Sn-based solders and electroless Ni–P metallization is an important cause of rapid degradation of solder joint reliability. In this study, to suppress formation of the Ni₃P phase, an electrolessly plated Ni–Sn–P alloy (6–7 wt.% P and 19–21 wt.% Sn) was developed to replace Ni–P. The interfacial microstructure of electroless Ni–Sn–P/Sn–3.5Ag solder joints was investigated after reflow and solid-state aging. For comparison, the interfacial reaction in electroless Ni–P/Sn–3.5Ag solder joints under the same reflow and aging conditions was studied. It was found that the Ni–Sn–P metallization is consumed much more slowly than the Ni–P metallization during soldering. After prolonged reaction, no Ni₃P or voids are observed under SEM at the Ni–Sn–P/Sn–3.5Ag interface. Two main intermetallic compounds, Ni₃Sn₄ and Ni₁₃Sn₈P₃, are formed during the soldering reaction. The reason for Ni₃P phase suppression and the overall mechanisms of reaction at the Ni–Sn–P/Sn–3.5Ag interface are discussed.     

HgCdTe阳极硫化+ZnS钝化膜表面与界面的研究

报道了HgCdTe阳极硫化+ZnS钝化膜表面与界面X射线光电子能谱(XPS)的研究及结果.系统地介绍了HgCdTe阳极硫化+ZnS钝化膜的制备,Br2-CH3OH与HgCdTe化学抛光的反应过程,阳极硫化的化学组成及生长机制.阐述了该钝化结构不同深度的组分分布及其对HgCdTe光伏器件电学特性的影响.     

1.3414μm Nd∶YAlO3激光泵浦的室温中红外Co∶MgF2激光器

报道了１３４１４μｍＮｄ∶ＹＡｌＯ３激光端面泵浦的室温２１０００μｍＣｏ∶ＭｇＦ２脉冲激光的实验结果,得到了２７９４ｍＪ能量输出,器件斜率效率达２３％,阈值能量为１２５ｍＪ。     

双折射率色散效应对液晶可调光衰减器的影响

文章利用Jones矩阵方法计算和分析了双折射率色散效应对一种液晶可调光衰减器(VOA)衰减能力的影响.结果表明,当激光谱线宽度较窄时,双折射率色散效应将导致液晶VOA的光衰减能力大幅度减弱;反之,双折射率色散效应对液晶VOA光衰减能力的影响可以忽略,但液晶VOA本身的光衰减能力很低.因此,液晶VOA适用于较窄线宽的激光光源,在设计和使用时应充分考虑液晶双折射率色散效应对其光衰减能力的影响.     

聚丙烯激光透射焊接工艺及性能研究

利用激光透射焊接技术对聚丙烯(PP)塑料进行焊接,研究了激光焊接热塑性塑料的可行性。通过正交试验法研究了激光功率、焊接速度、碳黑含量对焊接强度和焊接质量的影响。探讨了线能量对焊接强度的影响。结果表明:对PP材料来说,激光功率是首要影响因素,其次是焊接速度,最后是碳黑含量。最佳的焊接工艺参数为激光功率50 W,焊接速度15 mm/s,碳黑质量分数0.15%。线能量对焊接质量有较大影响,线能量在1.5~3 J/mm可得到较好强度的焊件。     

Atomic Insights into the Enhanced Surface Stability in High Voltage Cathode Materials by Ultrathin Coating

Surface properties of electrode materials play a critical role in the function of batteries. Therefore, surface modifications, such as coatings, have been widely used to improve battery performance. Understanding how these coatings function to improve battery performance is crucial for both scientific research and applications. In this study the electrochemical performance of coated and uncoated LiNi_0.5Mn_1.5O₄ (LNMO) electrodes is correlated with ensemble‐averaged soft X‐ray absorption spectroscopy (XAS) and spatially resolved scanning transmission electron microscopy‐electron energy loss spectroscopy (STEM‐EELS) to illustrate the mechanism of how ultrathin layer Al₂O₃ coatings improve the cycle life of LiNi_0.5Mn_1.5O₄. Mn²⁺ evolution on the surface is clearly observed in the uncoated sample, which results from the reaction between the electrolytic solution and the surfaces of LiNi_0.5Mn_1.5O₄ particles, and also possibly atomic structure reconstructions and oxygen loss from the surface region in LiNi_0.5Mn_1.5O₄. The coating effectively suppresses Mn²⁺ evolution and improves the battery performance by decelerating the impedance buildup from the surface passivation. This study demonstrates the importance of combining ensemble‐averaged techniques (e.g., XAS) with localized techniques (e.g., STEM‐EELS), as the latter may yield unrepresentative information due to the limited number of studied particles, and sheds light on the design of future coating processes and materials.     

基于乡村振兴背景的村庄规划设计策略探索——以龙山县尖岩村规划设计为例

本文以建构系统性的策略框架模型,有效助力乡村规划方案的运营实施并实现规划设计的建设为研究目的。从环境资源现状、村本产业情况、历史文脉资源等方面分析当前乡村规划设计现状及相关问题。阐明了乡村规划设计应平衡环境生态,注重基础功能设施完善,推动产业链闭合,实现多维度创新,重视历史文脉,重塑乡村肌理,打造特色田园,助推景村融合的设计策略。文章以龙山县尖岩村规划设计为例,进行乡村规划设计策略的探寻和实践,为实现全面乡村振兴构建一条科学高效的探索路径。     

超宽带网络异常流量检测与防治技术探析

随着网络接入带宽的不断提升,异常流量对网络的威胁日益严重,防治的需求更为紧迫。本文阐述了异常流量攻击防治技术的现状,并针对现有技术应用的不足,提出了基于云计算在全网范围内实现集中调度、并行处理、就近清洗的异常流量清洗方案,分析了该方案的优势,最后对异常流量攻击防治技术的研究进行了展望。     

应变In0.20 Ga0.80As／GaAs单量子阱结构的光谱研究

报道了用光致发光光谱，吸收光谱和光电流谱研究具有相同组伊阱宽，不同覆盖层厚度的应变Ｉｎ０．２０Ｇａ０．８０Ａｓ／ＧａＡｓ单量子阱结构的实验结果，结果理论计算，观察到ＧａＡｓ覆盖层厚度对单量子阱结构的材料质量，应力驰豫和发光淬灭机制的影响，确定了各样品应变值和导带不连续因子Ｑｃ，并讨论了这种结构发光机制。