微波印制电路板制造工艺及其电阻集成

介绍了微波印制电路板制造工艺中的钻孔、孔金属化和图形制作等主要步骤以及电阻集成的方法。通过在微波印制电路板基材表面涂覆低介电常数的材料,改变了基材表面形貌和特性,采用薄膜工艺在微波印制电路板上集成了30～50Ω/的NiCr电阻。最后简要介绍了微波多层印制电路新技术。     

钌系玻璃釉电位器电阻浆料设计原理及研制

本文作者在深入研究厚膜钌系电阻浆料基础上获得经验和原理，结合厚膜钌系电阻浆料的导电模型和微观结构，提出了玻璃釉电位器电阻浆料的设计原理和电阻表面状态一玻璃相半球模型，通过获得玻璃相表面半球状态，能使电阻表面和铜触点之间的张力与摩擦力匹配，从而本质上改变了电位器特征参数CRV值。通过试验证明在这种状态下，电阻值在50Ω/□、100Ω/□、1kΩ/□、10kΩ/□、100kΩ/□、1MΩ/□都获得了良好的CRV值，在非电阻表面玻璃相半球状态下，电阻CRV值迅速增大。     

ITO薄膜的电阻并联效应研究

采用电子束蒸发镀膜方法在K9玻璃基底上分别镀制了ITO/SiO₂/ITO,ITO/Ti₂O₃/ITO和ITO/MgF₂/ITO结构的多层薄膜,用四探针方块电阻仪测量薄膜表面的方块电阻,用原子力显微镜观测样品的表面微观形貌。结果显示,当ITO薄膜的粗糙度较大且介质薄膜的物理厚度小于100nm时,各层ITO薄膜之间通过山峰状的凸起结构相连通,导致样片表面的方块电阻测量值与各层ITO薄膜电阻的并联值相当。这表明,当ITO薄膜的粗糙度较大且介质薄膜厚度较小时,各层ITO薄膜表现出电阻并联效应。利用多层ITO薄膜的电阻并联效应设计并制备了450～1200nm超宽光谱透明导电薄膜,用四探针方块电阻仪测量了试验样片的表面方块电阻,用紫外-可见-近红外分光光度计测试了样片的光谱透射率。结果显示,在相同表面方块电阻条件下,相比于单层ITO薄膜,利用ITO薄膜电阻并联效应所制备的多层透明导电薄膜具有更高的光谱透射率。     

化学镀镍铜磷在钕铁硼表面处理上的应用研究

为提高钕铁硼表面镀层的耐蚀性,使其具有更高的经济附加值,采用在化学镀镍磷合金液中添加适量的铜离子及其复合络合剂,制得镍铜磷三元合金。研究了镍离子、铜离子、次亚磷酸钠、复合络合剂添加量,沉积温度、pH值对合金镀层沉积速度的影响。利用中性盐雾试验比较了其与电镀镍、化学镀镍磷合金的耐蚀性能。结果表明：化学镀镍铜磷合金能明显提高钕铁硼表面处理后的耐蚀能力。     

应用无掩膜印刷术埋嵌微型聚合物厚膜电阻

Optomec公司开发了一种名为M3DTM的新型印刷技术,用于沉积高精度PTF(Polymer Thick Film)电阻。这种新方法生产出的电阻,面积小到0.05mm2,阻值范围达到100Ω-10000Ω,阻值公差能够保持在10%以内。M3DTM技术可以直接利用CAD文件决定电阻的位置以及阻值大小,而不需要制作掩膜模版,也不需要事后对阻值进行微调,是一种印刷埋嵌电阻的高性价比解决方案。     

浅结密栅线硅太阳电池工艺研究

通过提高发射区方块电阻,配合密栅线丝网印刷工艺,制备了性能优良的多晶硅太阳电池。对比两种不同扩散工艺的方块电阻和ECV浓度,分析发射区方块电阻对太阳电池电性能参数的影响。结果表明:方阻为80Ω/□的发射区比70Ω/□的发射区的太阳电池串联电阻增加了0.03mΩ,导致填充因子下降0.05%,但是开路电压和短路电流密度分别提高了0.9mV和0.13mA/cm2,最终转换效率仍然提高了0.08%。     

PCB基材上化学镀Ni-P合金层用于埋置电阻的工艺方法研究

文章研究了在PCB基材上化学镀Ni-P合金层用于埋置电阻的工艺方法。基于埋入电阻在挠性及刚性PCB板中的应用,分别研究了Ni-P合金在无卤的FR-4、无卤的PI两种PCB基材上镀层厚度与试验时间之间的关系,初步得出了在两种不同基材上化学沉积Ni-P合金的规律,该规律对后期的试验具有重要的指导作用。     

电子元件表面化学镀镍的可焊性参数

许多电子器件、基片、管壳与散热片都有化学镀镍的部分,除要求易于焊接外,还可能要求具有其他功能,如要求有良好的抗蚀性等。在电子元件上采用可焊镍镀层,目的是让镍层起到如下作用:(1)非可焊基材上的可焊面层;(2)给能溶于熔融焊料的基材提供可焊面层,让镍成为防止基材渗入熔融锡铅焊料的阻挡层;(3)提供可焊面层,又同时用作扩散阻挡层,从而尽可能抑制生成不需要的基材合金与表面精饰金属所组成的金属间化合物。化学镀镍层用于含有如下基材的电子元件上:42合金(42％镍)、铝、陶瓷、冷轧钢、铜、ASTM—     

用脉冲CO_2激光辐照降低多晶硅的薄层电阻

本文报导用脉冲CO_2激光辐照磷扩散多晶硅,获得多晶硅薄层电阻从17Ω/□降低到7.4Ω/□的结果。并用扫描电子显微镜观察了激光辐照后的表面结构形貌。对激光辐照多硅的热稳定性也进行了初步研究。     

二氧化钌对钽钌酸铅厚膜电阻特性的影响

<正> 笔者对钽钌酸铅电阻曾进行了广泛而深入的研究,钽钌酸铅电阻具有以下特性:1.电阻对烧结温度不敏感;2.10kΩ/□～10MΩ/□范围内不需要掺杂且性能良好;3.电     

Influence of Phosphorus Content on the Interfacial Microstructure Between Sn–3.5Ag Solder and Electroless Ni–P Metallization on Cu Substrate

Under bump metallization (UBM), which usually consists of a few thin metallic layers, provides good solderable surface while protecting the underlying metallization from reacting with solder. Electroless nickel (Ni-P) with a thin layer of immersion gold has been considered as one of the promising candidates for under bump and substrate metallizations. However, the presence of P in electroless Ni-P causes more complicated interfacial reactions with solder than pure Ni. The amount of P in the Ni-P layer affects the soldering reaction in terms of microstructure and reaction kinetics. In this paper, influence of P content on the interfacial microstructure between Sn-3.5Ag solder and electroless Ni-P metallization on Cu substrate has been investigated. Electroless Ni-P layers of three different P contents (6.1, 8.8, and 12.3 wt.%) with the same thickness were plated on Cu substrate. Multilayered samples with Sn-3.5Ag/Ni-P/Cu stack were then prepared and subjected to multiple reflows. Various types of interfacial compounds (IFCs) such as Ni₃Sn₄, Ni₃P, Ni-Sn-P, Cu-Sn, and Ni-Cu-Sn formed depending upon the number of reflows. Ni₃Sn₄ intermetallic compound that formed in the low P sample was found to be more stable, whereas, Ni₃Sn₄ that formed in the medium and high P samples mostly spalled off into the molten solder during reflow. The Ni ₃Sn₄ spallation was found responsible for thicker Cu-Sn and Ni-Cu-Sn intermetallics in the medium and high P samples as compared to that of low P sample. Explanation for the observed interfacial microstructure is proposed in the paper in detail     

Effects of phosphorus content on the reaction of electroless Ni-P with Sn and crystallization of Ni-P

The reaction between electroless Ni-P and Sn and the crystallization behavior of Ni-P were investigated to better understand the effect of P content on the Ni-P layer. Electroless Ni-P specimens with three different P contents, 4.6 wt.%, 9 wt.%, and 13 wt.%, were used to study the effect of the P content and the microstructure of Ni-P on the subsequent crystallization and intermetallic compound (IMC) formation during the reaction between Ni-P and electroplated Sn. Ni₃Sn₄ was the major phase formed in all samples heated up to 300°C, which totally transformed into Ni₃Sn₂ when samples were heated up to 450°C and the Sn layer was 0.5-μm thick. The IMC formed on the nanocrystalline Ni-P showed stronger texture compared to that formed on the amorphous Ni-P. Both the IMC thickness and density decreased with P content in the Ni-P layer, and Ni₃Sn₄ morphologies varied with P content. Dissolution of Ni into Sn increased with P content, which made IMC size in the bulk Sn increase with P content.     

不同阻值电阻分压器对MOV残压测试的影响

冲击电阻分压器是测量压敏电阻(Metal Oxide Varistor,MOV)残压必不可少的设备之一,为了测量残压的准确性,利用三组不同分压器对高压臂电阻值优选范围进行试验研究,同时在源阻抗为0.45Ω和1.1Ω的8/20μs波形冲击电流发生器下进行MOV残压试验。试验结果表明冲击电压发生器源阻抗低时,A、B、C三组分压器在20kA下测得残压不会发生分压比线性偏离,20kA以上高压臂阻值越高,分压器越稳定;冲击电压发生器源阻抗上升至1.1Ω时,A、C分压器在不同冲击电流下测试分压比均稳定,高压臂阻值对测量MOV残压影响很小。     

激光熔敷PdCuSi合金非晶涂层的研究

研究了采用５ｋＷＣＯ２连续激光器和２００ＷＹＡＧ脉冲激光器在Ｃｕ基材上进行熔敷ＰｄＣｕＳｉ合金非晶态涂层，讨论了两种激光器辐照条件下该合金的非晶形成能力和Ｎｉ－Ｐ非晶预镀层的作用。     

激光热处理对化学沉积Ni-P合金薄膜性能的影响

用扫描电镜(SEM)观察了化学沉积Ni-P合金薄膜/单晶硅基体的结构与颗粒度,利用X射线衍射(XRD)技术测试了其化学沉积后的残余应力,测量了激光热处理后残余应力的变化规律,分析了残余应力对磨损性能及界面结合强度的影响。实验结果表明,化学沉积Ni-P合金薄膜/硅基体的残余应力均表现为拉应力,经过激光热处理后残余应力发生了变化,由高值的拉应力变为低值的拉应力或压应力;薄膜残余应力对其磨损性能有明显的影响,其磨损量随着残余应力的减小而减小;薄膜与基体结合强度随着残余应力的增大而减小,合理地选择激光热处理参数可以精确地控制薄膜残余应力,提高其结合强度。     

PTCR陶瓷化学沉积镍电极界面结构及特性的研究

通过伏安特性和阻温特性测试研究了不同沉积条件下所得化学沉积镍电极BaTiO3基半导瓷热敏电阻元件的电性能，利用扫描电镜、透射电镜和X—衍射等现代分析手段，重点分析了在不同工艺条件下得到的化学镀镍电极与PTCR陶瓷之间的纳米界面结构及其特性，得到良好的欧姆接触化学镀镍电极的实验参数。     

一种高性能氧化钒热敏薄膜的制备和应用

报道一种制备高性能氧化钒热敏薄膜的方法和其应用。采用反应磁控溅射薄膜沉积技术，通过改变氧化钒热敏薄膜沉积时溅射功率，从而调整钒原子在溅射出来之后接触到基片表面时的沉积速率，同时通过对设备进行改造升级，即在钒溅射腔腔外增加一个控制电源来精确控制溅射电压及氧气分压等参数来精确控制反应过程中电流密度，优化了氧化钒薄膜的制备工艺，制备出方块电阻为500 kΩ/□，电阻温度系数（TCR）为?2.7% K?1的氧化钒薄膜。实验测试结果表明，利用高性能氧化钒热敏薄膜制作的非制冷红外焦平面探测器，其噪声等效温差（NETD）降低30%，噪声降低28%，显著提升了非制冷焦平面探测器的综合性能。     

Effects of the ink concentration on multi-layer gravure-printed PEDOT:PSS

To date, highly conductive PEDOT:PSS is the most promising transparent electrode for printing-based flexible organic electronics. Spin-coating and slot-die coating have been commonly used for printing this material. Among the roll-to-roll printing processes, gravure is the most promising for manufacturing large area electronics offering the advantages of high speed and high printing definition. However, gravure printing highly conductive PEDOT encounters some technological limitations such as low thickness, layer inhomogeneity and high surface roughness resulting in a layer not suitable as electrode in electronic devices. In order to realize an electrode of highly conductive PEDOT by gravure printing, a multilayer approach with variable ink concentration was tried using IPA as process solvent. Variable solvent amount of overlapped printed layers was found to play an important role in the spreading of the PEDOT ink onto the pre-printed layers and in the smoothing of its existent peaks. In particular, adopting increasing ink dilution with increasing of the overlapped layers, multi-layer gravure-printed highly conductive PEDOT was successfully realized with characteristics suitable as transparent electrode for organic electronic devices (sheet resistance lower than 130 Ω/sq, conductivity higher than 450 S/cm and optical transmittance over 80%). This is the first time that such results were reached by gravure printing technique thanks to the easy proposed approach.