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251.
针对近年来惯性类组合产品朝微型化发展趋势,设计了一种新型的微型惯性组合封装技术。介绍了该技术所涉及装置的构成及封装过程,专门设计了相应的挤压头,并对影响最终铆封接头成型的挤压量做了精心设计。将应用该技术后的产品进行了振动冲击试验和有限元仿真分析。结果表明,振动冲击后的产品铆封接头没有失效情况出现;而有限元分析结果显示,铆封接头边缘的最大位移值为0.01 mm。由此判定铆封接头牢固可靠。这种微型化封装技术不仅应用于惯性组合,同样也适用于其他行业的产品,有很高的推广价值。 相似文献
252.
采用晶圆级芯片尺寸封装(WLCSP)工艺完成了一款小型化CMOS驱动器芯片的封装.此WLCSP驱动器由两层聚酰亚胺(PI)层、重分配布线层、下金属层和金属凸点等部分构成.完成了WLCSP驱动器的设计,加工和电性能测试,并且对其进行了温度冲击、振动和剪切力测试等可靠性试验.结果表明,经过晶圆级封装的CMOS驱动器体积为1.8mm×1.2mm×0.35 mm,脉冲上升沿为2.3 ns,下降沿为2.5ns,开关时间为10.6 ns.将WLCSP的驱动器安装至厚度为l mm的FR4基板上,对其进行温度冲击试验及振动试验后,凸点正常无裂痕.无下填充胶时剪切力为20 N,存在下填充胶时,剪切力为200 N. 相似文献
253.
Vinylidene chloride copolymers are prominent in the barrier plastic packaging industry. These materials display excellent
barrier to the transport of oxygen (and other small molecules) as well as flavor and aroma molecules. However, they suffer
from a propensity to undergo degradative dehydrochlorination at process temperatures. To scavenge hydrogen chloride formed
and prevent its interaction with the metallic components of process equipment, a passive base is usually included as an additive
prior to processing. The base is most often an inorganic oxide or salt. These may negatively impact the properties of the
polymer, particularly as a film. An organic base that could be covalently incorporated into the copolymer might display better
behavior. Accordingly, a series of copolymers containing low levels of 4-vinylpyridine (0.05–3 mole%) have been prepared,
characterized, and examined by thermogravimetry to assess thermal stability. In all cases, polymers containing 4-vinylpyridine
units are less stable than the polymer containing none of this comonomer. Clearly, the pyridine moiety is a sufficiently strong
base to promote E2 elimination of hydrogen chloride to generate dichlormethylene units in the mainchain from which thermal
degradation may be initiated. 相似文献
254.
《Microelectronics Journal》2015,46(3):231-236
Devices that are compact in design and fabrication continue to draw attention for specific applications that require high performance. A compact elliptic bandpass filter using a cross-coupled topological structure with a hairpin resonator optimised for radar applications is presented in this paper. This work presents the design theory and corresponding semiconductor fabrication processes and describes the chip-on-board packaging method in detail. The proposed design of the bandpass filter can not only reduce the size of the device and result in good RF performance, but the accurate semiconductor fabrication process can also ensure high performance further. In addition, the presented chip-on-board packaging method can greatly enhance the reliability and long-term stability of a microwave device, which rarely introduces RF characteristic interference. The simulated, bare-chip measured and final chip-on-board measured results agreed well, which validated the correctness of the proposed approach. 相似文献
255.
《Helvetica chimica acta》2018,101(3)
Here we present a novel active surface that demonstrates pH responsiveness and can be used as a platform for designing ‘smart labels’. To generate our active surfaces, we immobilized polymer nanocompartments onto glass surfaces using thiol–ene chemistry. Prior to surface attachment, a pH responsive model dye was encapsulated within nanocompartments at two different pH values. We confirmed the attachment and distribution of dye‐loaded polymersomes and established the pH responsiveness of the active surface construct. The strategy presented here was carefully chosen to obtain small sized functional surfaces from commercially available materials that can be easily integrated into intelligent packaging systems. The ability to miniaturize such smart labels, while still being able to detect their response to the environment, is a crucial step towards developing active surfaces suitable for food packaging applications. 相似文献
256.
As an alternative to the time-consuming solder pastes and preforms currently being used, a method of electroplating the eutectic
Au/Sn alloy has been developed. Using a pulsed co-deposition process, it is possible to plate the solder directly onto a wafer
at or near the eutectic composition from a single solution. It has been shown that two distinct phase, Au5Sn and AuSn, can be deposited separately over a range of current densities at compositions of 15 at. %Sn and 50 at. %Sn, respectively.
by adjusting the deposition current pulse, it is possible to plate both phases in a layered composite thereby achieving any
desired composition between 15 and 50 at. %Sn, including the commercially important eutectic composition. 相似文献
257.
本文从应用的观点出发简要介绍了各种封装技术在新世纪中的发展趋势。论述了如CSP、BGA 及倒装芯片等先进封装技术在微电子工业中所发挥的重要作用。 相似文献
258.
259.
Thanas Budri 《Applied Surface Science》2008,254(15):4768-4773
In this paper, we summarize how the introduction of in-line TXRF monitoring provides detailed analytical information on aluminum, titanium and molybdenum contamination levels in order to improve several process steps from front-end processing, minimize product yield loss and make it possible to successfully manufacture multiple products and process geometries in the same fabrication platform. 相似文献
260.