共查询到20条相似文献,搜索用时 640 毫秒
1.
R. Raman Ashok Kumar Kapoor Shiv Kumar Akhilesh Pandey 《Journal of Electronic Materials》2009,38(10):2046-2051
Colloidal silver is observed to affect the transmittance of p-type Cd1−y
Zn
y
Te (CZT) single-crystal substrate material at room temperature. The optical transmittance spectra have been analyzed in the
near-infrared (NIR) and mid-infrared (MIR) regions. The transmittance characteristics of CZT showed significant reduction
in absorption due to split-off valance band transitions in the NIR region and intervalence band absorption in the MIR region
upon coating CZT substrates with silver paste. This reduction in absorption has been explained to be due to the compensation
of the acceptor defects (native and foreign). Silver atoms incorporated from the silver coating help in compensation of these
defects. A similar effect on transmittance characteristics of mercury cadmium telluride (MCT) epilayers grown on CZT substrates
after coating silver paste on the CZT substrate side was also observed. An improvement in the transmittance of CZT substrates
after the application of silver paste was observed. A similar improvement in transmittance is usually achieved by annealing
the substrates in a Cd/Zn atmosphere. The results are explained by considering the formation of neutral complexes of acceptors
(cadmium vacancies) and the interstitial silver. This study also points to the important conclusion that silver paste on CZT
should be applied with caution for measurement purposes since it diffuses even at room temperature and modifies the optical
characteristics. 相似文献
2.
Jianguo Liu Xiangyou Li Xiaoye Wang Xiaoyan Zeng 《Journal of Electronic Materials》2010,39(10):2267-2273
A homogeneous electrically conductive silver paste without solid or particle phase was developed using silver alkylcarbamates
[(C
n
H2n−1NHCOO)2Ag, n ≤ 4] as the precursor of the functional phase. The silver alkylcarbamates were light insensitive and had a low decomposition
temperature (below 200°C). The paste was a non-Newtonian fluid with viscosity significantly depending on the content of the
thickening agent ethyl cellulose. Array patterns with a resolution of 20 μm were obtained using this paste by a micropen direct-writing method. After the paste with about 48 wt.% silver methylcarbamate
[(CH3NHCOO)2Ag] precursor was sintered at 180°C for 15 min, an electrically conductive network consisting of more than 95 wt.% silver
was formed, and was found to have a volume electrical resistivity on the order of 10−5 Ω cm and a sheet electrical resistivity on the order of 10−2–10−3 Ω/□. The cohesion strength within the sintered paste and the adhesion strength between the sintered paste layer and the alumina
ceramic substrate were tested according to test method B of the American Society for Testing and Materials standard D3359-08.
None of the sintered paste layer was detached under the test conditions, and the cohesion and adhesion strengths met the highest
grade according to the standard. 相似文献
3.
银/导电陶瓷复合电极浆料导电性的研究 总被引:2,自引:2,他引:0
采用银和导电陶瓷(LaNiO3和LaFe0.25Ni0.75O3)作复合电极浆料,并研究了复合电极浆料的导电性与导电陶瓷比例及种类的关系。结果发现,复合电极浆料的电阻率随导电陶瓷比例的增加而增大,当LaNiO3和LaFe0.25Ni0.75O3两种导电陶瓷的质量分数<15%时,两种复合浆料的导电性均变化不大。SEM观测显示,复合电极浆料制成的电极有很好的烧成表面。 相似文献
4.
从排胶和共烧两方面 ,研究了氮化铝 ( Al N) /玻璃复合材料的低温共烧。排胶研究结果表明 :流延坯片和银浆的排胶特性不同 ,氧化性气氛有利于两者的排胶。共烧研究表明 :Al N/玻璃复合系统的烧结为液相烧结 ;引入微氧烧结气氛将改变界面状况 ,有利于 Al N/玻璃复合材料和银共烧的实现 相似文献
5.
Selim Achmatowicz Konrad Kie?basiński El?bieta Zwierkowska Valentinas Baltrušaitis 《Microelectronics Reliability》2009,49(6):579-584
A new thick-film photoimageable platinum paste has been elaborated. The paste is less sensitive to the visible light. The resolution line/space 20/30 μm is achievable. The application of the elaborated paste to produce heaters is demonstrated. The stability of the heaters has been evaluated. 相似文献
6.
7.
Guofeng Bai J. Jian Yin Zhiye Zhang Guo-Quan Lu van Wyk J.D. 《Advanced Packaging, IEEE Transactions on》2007,30(3):506-510
In this paper, we present the realization of high-temperature operation of SiC power semiconductor devices by low-temperature sintering of nanoscale silver paste as a novel die-attachment solution. The silver paste was prepared by mixing nanoscale silver particles with carefully selected organic components which can burn out within the low-temperature firing range. SiC Schottky diodes were placed onto stencil-printed layers of the nanoscale silver paste on Au or Ag metallized direct bonded copper (DBC) substrates for the die-attachment. After heating up to 300degC and dwell for 40 min in air to burn out the organic components in the paste and to sinter the nanoscale silver, the paste consolidated into a strong and uniform die-attach bonding layer with purity >99% and density >80%. Then the die-attached SiC devices were cooled down to room temperature and their top terminals were wire-bonded to achieve the high-temperature power packages. Then the power packages were heated up from room temperature to 300degC for high-temperature operation and characterization. Results of the measurement demonstrate the low-temperature silver sintering as an effective die-attach method for high-temperature electronic packaging. An advanced packaging structure for future SiC transistors with several potential advantages was also proposed based on the low-temperature sintering technology. 相似文献
8.
In this paper, the effect of silver oxalate addition on physical characteristics of metallo-organic-decomposition (MOD) silver screen-printable paste for thick film technology was investigated. The addition of silver oxalate in the paste not only produces fresh fine silver particles after curing, but also reduces the decomposition temperature of the lubricant coated on the silver flakes. This is an effective route to provide fine silver particles to the paste without significantly changing the rheological behavior. At the curing temperature of 225 °C, the resistivity decreases from 180.1 to 31.9 μΩ-cm, as the silver oxalate content increases from 0 to 10 wt%. This is due to the fact that active silver catalysts produced increase the packing density of silver flakes, and also the removal of lubricant from the surface of silver flakes enhances the electrical conductivity, thereby decreasing the resistance of film. 相似文献
9.
Micrometric-sized pixels of hybrid organic–inorganic thin films (Ag/parylene-C) have been printed by laser-induced forward transfer (LIFT) on flexible, cost-efficient substrates. Micrometric capacitors have been fabricated by laser printing such pixels together with silver nanoparticles (AgNP) paste. The AgNP paste has been deposited in the shape of square pads, acting as bottom electrode. This combination is suitable to be used in microelectronic circuits, as the electrical components exhibit controllable capacity in the pF–nF range. Electrical characterizations of the printed pixels demonstrate that the capacitors are fully operative and stable over time. 相似文献
10.
MLCI银端浆的无铅化研究 总被引:2,自引:1,他引:1
由无铅、无镉低软化点玻璃料、银粉、有机载体制备而成的银端浆具有烧结温度低、适用范围广等特点.实验结果表明:本浆各项技术指标、工艺性能良好,完全能满足多(叠)层片式电感器(MLCI)生产线的使用要求,并可用于制作绕线电感器(WWCI)与片式电容器(MLCC)的端电极. 相似文献
11.
12.
电子浆料用球形银粉的制备 总被引:6,自引:1,他引:5
介绍了化学沉淀法生产球形银粉的工艺技术,采用该工艺制备的球形银粉具有良好分散性、合适的粒径、适当的比表面积,可以广泛应用于电子浆料. 相似文献
13.
为了得到更稳定、可靠的片式NTC热敏电阻器,在芯片表面涂覆一层玻璃釉是有效的途径之一。为此调整了玻璃釉包覆片式NTC热敏电阻器所进行的工艺,进行了玻璃浆及银浆的选取和匹配工作。所研制的片式NTC热敏电阻器,克服了传统片式NTC热敏电阻的精度不高、稳定性不好、可靠性差等主要缺点,F级阻值合格率提高了45%,阻值的年漂移小于0.1%,端电极强度提高了约4.9N,耐焊上锡率提高了约5%。 相似文献
14.
15.
Multilayer resonators and a bandpass filter fabricated from a novel low-temperature co-fired ceramic 总被引:1,自引:0,他引:1
H. Jantunen S. Leppävuori A. Turunen A. Uusimäki 《Journal of Electronic Materials》2002,31(3):191-195
The main objective of this study was to make components from a novel low-loss, low-temperature Co-fired ceramic (LTCC) dielectric,
which was also compatible with a high-conductivity silver paste. The multilayer-component fabrication procedure is presented
together with a composition for a tape-casting slurry, choice of conductor paste, and LTCC process parameters. A good Q factor,
>100 at 2 GHz, using the novel material system has been achieved for λ/2 resonators operating in the frequency range 1.7–3.7
GHz. An excellent frequency response for a 2 GHz bandpass filter has also been achieved; the insertion losses in the passband
were less than −2 dB (bandwidth 60 MHz) and the attenuation more than 25 dB in the stopband located 190 MHz higher. 相似文献
16.
在Ag导电胶上化学镀铜工艺 总被引:1,自引:0,他引:1
概述了由Ag导电胶形成的Ag导电膜上的化学镀铜工艺,其特征在于采用新的活化工艺取代传统的Pd催化剂,可以在Ag导电膜上形成均匀致密,无镀层扩展和优良附着性的化学镀铜层,特别适用于印制板的Ag导电胶上选择性化学镀铜。 相似文献
17.
We have explored the electrical conductivity of thick films made from silver methylcarbamate paste using metallic silver as the electrically conductive phase. The paste was composed of 30 wt.% to 90 wt.% organic vehicle and 10 wt.% to 70 wt.% functional phase precursor (silver methylcarbamate). After the paste was sintered, films with thickness of 4.50 μm to 12.70 μm were obtained, in which the elemental percentage of silver varied from about 5 wt.% to above 99 wt.%. Experiments showed that both the electrical conductivity and the elemental percentage were mainly affected by the initial silver content in the paste and the parameters of the sintering process. For given sintering conditions, higher initial silver content led to higher elemental percentage of silver, improving the electrical conductivity of the thick film. The conditions of the sintering process had a significant influence on the evaporation and decomposition rates of the paste components, the elemental percentage of silver, and the microstructure of the thick film. Higher temperatures, longer times, lower heating rates, and more oxygen-rich sintering atmospheres were found to accelerate the evaporation and decomposition and increase the elemental percentage of silver, both of which served to enhance the electrical conductivity. For initial silver contents less than about 10 wt.%, the lowest electrical resistivity of the thick film only reached the order of 10?4 Ω cm, irrespective of the sintering conditions. For contents between 10 wt.% and 25 wt.%, it was possible to attain lowest resistivity values on the order of 10?5 Ω cm. Above 25 wt.%, the lowest resistivity could reach 10?6 Ω cm, comparable to that of bulk silver. 相似文献
18.
19.
超细银粉在有机介质中的分散及其稳定性 总被引:8,自引:2,他引:6
研究了银粉对银浆的分散及稳定性的影响 ,对浆料中粒子间的作用进行了探讨 ,找出了影响超细银粉在有机载体中分散的若干关键因素。根据对银粉团聚程度的分析和银浆流变学行为研究的结果 ,以及对有机介质链接特性的改进 ,可制出印刷特性优良 ,分散稳定的电子浆料 相似文献
20.
Hani Alarifi Anming Hu Mustafa Yavuz Y. Norman Zhou 《Journal of Electronic Materials》2011,40(6):1394-1402
Silver nanoparticle (NP) paste was fabricated and used to bond copper wire to copper foil at low temperatures down to 160°C.
The silver NP paste was developed by increasing the concentration of 50 nm silver NP sol from 0.001 vol.% to 0.1 vol.% by
centrifugation. The 0.001 vol.% silver NP sol was fabricated in water by reducing silver nitrate (AgNO3) using sodium citrate dihydrate (Na3C6H5O7·2H2O). The bond was formed by solid-state sintering among the individual silver NPs and solid-state bonding of these silver NPs
onto both copper wire and foil. Metallurgical bonds between silver NPs and copper were confirmed by transmission electron
microscopy (TEM). The silver NPs were coated with an organic shell to prevent sintering at room temperature (RT). It was found
that the organic shell decomposed at 160°C, the lowest temperature at which a bond could be formed. Shear tests showed that
the joint strength increased as the bonding temperature increased, due to enhanced sintering of silver NPs at higher temperatures.
Unlike low-temperature soldering techniques, bonds formed by our method have been proved to withstand temperatures above the
bonding temperature. 相似文献