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所谓“钼锰法”就是采用金属化、镀镍随后用焊料焊接以形成陶瓷金属密封封接的许多方法中的一种。用这种方法将高氧化铝(94%Al_2O_3)瓷圆片和可伐件封接在一起。测量了封接层的抗张强度并用光学显微镜和扫描电子显微镜以及电子探针微分析仪来检查和分析了封接层.其结果如下: (1)当陶瓷在1450℃保温60分钟的条件下金属化时,封接层的抗张强度最大。 (2)封接层是由许多层构成的,这些层按下列次序排列: 陶瓷-中间层-金属化层一镀镍层-硬焊料层一镀镍层-可伐。中间层是由Al_2O·MnO和MgO以及少量的SiO_2和CaO-起组成的。层中的主要结晶相是MnO·A_2O_3。中间层的厚度与其相邻的金属化层的厚度成比例。 (3)铝-锰金属化层中的气孔被玻璃相和镍填充,前者来自陶瓷,后者来自镀镍层。这些物质的渗入和相互扩散形成牢固的真空密封层. 相似文献
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一、前言 陶瓷-金属封接是微波半导体器件的主要封装形式,随着器件可靠性的不断提高,要求陶瓷-金属的封接强度越高越好。影响陶瓷-金属封接强度的因素很多,择其要者,有以下四点: (1)、陶瓷与金属化配方的适应性。 (2)、金属化工艺规范——金属化烧结温度和保温时间。 (3)、金属化涂膏层的厚度。 (4)、焊料量。 本文就上述四因素对陶瓷-金属封接强度的影响,作一些初浅的探讨。 二、实验 1、样品 为接近实际使用情况,采用图1所示的样 相似文献
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镍基合金光束粉末堆焊质量的研究 总被引:1,自引:0,他引:1
研究了堆焊工艺和材料对镍基合金光束粉末堆焊质量的影响规律。为获得优质堆焊层 ,预涂层的宽度必须小于光斑直径 ,较大的预涂厚度会导致堆焊层与基材结合不良 ,厚度较小时 ,因过高的稀释率使堆焊层宏观硬度显著下降。采用多层焊和多道搭接工艺可获得大厚度、大面积堆焊层。堆焊层横向裂纹、焊道边缘气孔及层间未熔合是多层堆焊时易产生的缺陷。大面积堆焊时 ,焊趾位置会因选择性润湿而出现未搭接。合理控制堆焊线能量、对前道焊缝的清理以及堆焊过程中加强对熔池的保护 ,是获得大厚度、大面积堆焊层的关键。在镍基合金中加入与其相互润湿的金属陶瓷相 (镍包WC) ,并控制其加入量可获得无缺陷的、更高硬度的复合堆焊层。 相似文献
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85年12月份在国内首次研究出金属陶瓷结构的氩离子激光器。但是长度一米、内径均匀、直线性好的气密95氧化铝陶瓷管,国内至今仍不能生产。我们经大量调研和反复试验,用内径经过研磨的100毫米长的95氧化铝管,采用分段焊接法,初步制成金属陶瓷结构氩离子激光器用的长陶瓷管。具体焊接工艺流程如下:1.将内径研磨加工(误差<±0.1毫米),长度为100毫米的95氧化铝管两端采用高温钼锰法进行金属化处理;2.在金属化层上电镀4微米的镍膜;3.在950~1000℃的干氢中烧结20分钟,使镍膜与金属化层之间结合牢固; 相似文献
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采用活化Mo-Mn法对99%氧化铍陶瓷进行了金属化实验和抗拉强度实验.封接强度实验结果表明,活化Mo-Mn法适合99%氧化铍陶瓷金属化封接,其焊接强度与氧化铝陶瓷相当.通过对99%氧化铍陶瓷金属化层的显微结构及金属层中的元素在金属层及陶瓷中的分布情况分析,探讨了99%氧化铍陶瓷Mo-Mn金属化机理.研究发现,99%氧化铍陶瓷金属化时,在氧化铍陶瓷和Mo海绵骨架中间形成了一层约3μm的过渡层,金属化层的Mo海绵骨架结构通过过渡层与氧化铍陶瓷基体紧密连接. 相似文献
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MEMS THz滤波器的制作工艺 总被引:2,自引:0,他引:2
基于MEMS技术制作了太赫兹(THz)滤波器样品,研究了制作滤波器的工艺流程方案,其关键工艺技术包括硅深槽刻蚀技术、深槽结构的表面金属化技术、阳极键合和金-硅共晶键合技术。采用4μm的热氧化硅层作刻蚀掩膜,成功完成了800μm的深槽硅干法刻蚀;采用基片倾斜放置、多次离子束溅射和电镀加厚的方法完成了深槽结构的表面金属化,内部金属层厚度为3~5μm;用硅-玻璃阳极键合技术和金-硅共晶键合技术实现了三层结构、四面封闭的波导滤波器样品加工。测试结果表明,研制的滤波器样品中心频率138GHz,带宽15GHz,插损小于3dB。 相似文献
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压片预置式激光多层熔覆厚纳米陶瓷涂层结合性能 总被引:3,自引:1,他引:2
采用压片预置式激光多层熔覆制备了厚纳米Al2O3-13%TiO2(质量分数)涂层,研究了涂层的微观组织和结合性能,并分析了涂层厚度对结合强度的影响。结果表明,陶瓷涂层各层之间无明显界面,过渡缓和自然,涂层内部致密、连续,基本无孔隙及贯穿性大裂纹等缺陷;涂层由等轴晶的完全熔化区和残留纳米颗粒的部分熔化区组成,并且涂层中的裂纹基本集中于部分熔化区,另外晶粒尺寸表现为上小下大的梯度过渡特征。随着涂层厚度的增加,结合强度逐渐下降,其减小的趋势为先快后慢。厚度为175μm的试样结合强度高于78.6 MPa,而厚度为350、525、700μm的涂层结合强度分别为66.3、47.4、36.2MPa。 相似文献
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用保角变换法对共面波导金属厚度效应进行了理论分析,编制了相应的计算机程序,给出了数值解,并对此进行了多元曲线拟合,导出了考虑金属厚度后的形状比k、有效介电常数、特征阻抗、损耗的闭定表达式。用此修正表达式求得特征阻抗及损耗的数值解,并与K.C.格普塔的修正值及实验测量值进行了详细比较,结果表明此修正公式与实验值相符较好。 相似文献
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Large Multipurpose Exceptionally Conductive Polymer Sponges Obtained by Efficient Wet‐Chemical Metallization
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Markus Langner Seema Agarwal André Baudler Uwe Schröder Andreas Greiner 《Advanced functional materials》2015,25(39):6182-6188
Exceptionally conductive (250 S cm?1), very fast electrically heatable, thermally insulating, antimicrobial 3D polymeric sponges with very low density (≈30 mg cm?3), superhydrophobicity, and high porosity, their method of preparation, and manifold examples for applications are presented here. The electrical heatability is reversible, reaching 90 °C with 4.4 W in about 19–20 s and cooling immediately on switching off the voltage. The sponges show high contact angles >150° against water on the sponge surface as well as inside the sponge. Water droplets injected into the sponges are ejected. A facile wet‐chemical method established for macroscopic melamine–formaldehyde sponges is the key for the thorough in‐depth surface metallization of the sponges. The coating thickness and uniformity depend on the metallization formulation, conditions of metallization, and the type of metal used. A scanning electron microscope is used for morphology characterization. A reduced metallization rate in air is highly critical for the in‐depth uniform coating of metals. The resulting metallized sponges could be highly interesting for heating as well as insulation devices in addition to oil/water separation membranes. 相似文献
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Hutt D.A. Liu C. Conway P.P. Whalley D.C. Mannan S.H. 《Components and Packaging Technologies, IEEE Transactions on》2002,25(1):98-105
Electroless nickel has been used for many decades to provide a hard, corrosion resistant surface finish to engineering components. In recent years, its application has been extended to the electronics industry for the production of solderable surfaces on printed circuit boards, which utilize a further thin gold coating to prevent oxidation of the nickel surface. The recent interest in the use of flip-chip technology in electronics manufacture has required the development of low cost methods for solder bumping of semiconductor wafers. The electroless nickel process has been considered as a suitable candidate for the deposition of a solderable under bump metallization (UBM) layer onto the Al bondpads. However, the extension of existing electroless nickel plating processes to this new application requires greater understanding of the technique. In particular, the coating of the small isolated bondpads on the wafer surface introduces difficulties that make the use of many commercially available solutions impossible. This paper reports the results of a number of experiments carried out to investigate the electroless nickel bumping of Al bondpads and highlights the issues that need to be considered when selecting materials and techniques 相似文献
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An extensive analysis, based on a full-wave mode-matching technique, is described for coplanar strips (CPS) incorporating the strips' finite metallization thickness. Results for the effective dielectric constant and characteristic impedance are presented to show the effect of the metallization thickness. It is found that the characteristic impedance has a strong dependence on the metallization thickness, which signifies the fact that the finite metallization thickness needs to be considered in designing practical microwave circuits employing CPS. Numerical results of CPS with zero metallization thickness obtained using this method are found to be in good agreement with those published previously. Extensive investigation of the numerical convergence of these results is also described 相似文献