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71.
Yunlong Sun 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2002,90(10):1627-1636
Link processing with individual laser pulses has become an industry standard process in IC memory chip manufacturing. It is gaining wide acceptance in analog chip reprogramming and tuning as well. Traditional laser processing, using the standard output of Nd:YAG at 1.064-/spl mu/m and Nd:YLF at 1.047-/spl mu/m laser wavelengths, works well for polysilicon links but is not satisfactory for metal links. This paper describes the physics modeling and computer simulation of the laser link process and a new technique of using 1.3-/spl mu/m laser wavelength for the process. While light absorption of link materials at 1.064-, 1.047-, and 1.3-/spl mu/m wavelengths are relatively the same, the absorption of a Si substrate at 1.3 /spl mu/m is considerably less. The improved absorption contrast between the link material and silicon substrate at 1.3-/spl mu/m delivers a much wider laser process window. Both simulation and experimental results are given and discussed. A brief introduction of another new technique, which uses UV laser pulses for link processing, is given. This UV laser process delivers a laser beam spot size much smaller than 1.5 /spl mu/m. 相似文献
72.
Zhi Jiang Yang Wang Shuoguo Yuan Lu Shi Ni Wang Jie Xiong Wenhui Lai Xuanyu Wang Feiyu Kang Wei Lin Ching Ping Wong Cheng Yang 《Advanced functional materials》2019,29(9)
Commercial aluminium electrolyte capacitors (AECs) are too large for integration in future highly integrated electronic systems. Supercapacitors, in comparison, possess a much higher capacitance per unit volume and can be embedded as passive capacitors to address such challenges in electronics scaling. However, the slow frequency response (<101 Hz) typical of supercapacitors is a major hurdle to their practical application. Here, it is demonstrated that 1T‐phase MoSe2 nanosheets obtained by laser‐induced phase transformation can be used as an electrode material in embedded micro‐supercapacitors. The metallic nature of MoSe2 nanosheet‐based electrodes provides excellent electron‐ and ion‐transport properties, which leads to an unprecedented high‐frequency response (up to 104 Hz) and cycle stability (up to 106 cycles) when integrated in supercapacitors, and their power density can be ten times higher than that of commercial AECs. Furthermore, fabrication processes of the present device are fully compatible with system‐in‐package device manufacturing to meet stringent specifications for the size of embedded components. The present research represents a critical step forward in in‐package and on‐chip applications of electrolytic capacitors. 相似文献
73.
F. Tao Y. Liang G. Yin D. Xu Z. Jiang H. Li M. Han Y. Song Z. Xie Z. Xue J. Zhu Z. Xu L. Zheng X. Wei Y. Ni 《Advanced functional materials》2007,17(7):1124-1130
Highly ordered arrays of submicrometer‐sized coaxial cables composed of submicrometer‐sized C60 and C70 tubes filled with Ni nanowires are successfully prepared by combining a sol–gel method with an electrodeposition process. The wall thickness of the submicrometer‐sized tubes can be adjusted by the concentration of fullerenes and the immersion time. The thermal stability of the submicrometer‐sized C60 tubes is studied by Raman spectroscopy and it is found that these structures can be easily decomposed to form carbon nanotubes at relatively low temperatures (above 573 K) in an alumina template. These novel coaxial cable structures have been characterized by transmission electron microscopy (TEM), high‐resolution TEM (HRTEM), scanning electron microscopy (SEM), field‐emission SEM (FESEM), Raman spectroscopy, elemental mapping, energy dispersive X‐ray (EDX) spectroscopy, X‐ray diffraction (XRD), vibrating sample magnetometer (VSM) experiments, and superconducting quantum interference device (SQUID) measurements. Magnetic measurements show that these submicrometer‐sized cables exhibit enhanced ferromagnetic behavior as compared to bulk nickel. Moreover, submicrometer‐sized C70/Ni cables show uniaxial magnetic anisotropy with the easy magnetic axis being parallel to the long axis of the Ni nanowires. C70/Ni cables also exhibit a new magnetic transition at ca. 10 K in the magnetization–temperature (M–T) curve, which is not observed for the analogous C60/Ni structures. The origin of this transition is not yet clear, but might be related to interactions between the Ni nanowires and C70 molecules. There is no preferred magnetization axis in submicrometer‐sized C60/Ni cables, which implies that the Ni nanocrystals have different packing modes in the two composites. These different crystalline packing modes lead to different magnetic anisotropy in the two composites, although the Ni nanocrystals have the same face‐centered cubic (fcc) structure in both cases. 相似文献
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Yu Zhang Zefeng Ni Chuan Heng Foh Jianfei Cai 《Communications Letters, IEEE》2007,11(6):498-500
We investigate the packet loss behavior in the IEEE 802.11e wireless local area networks (WLANs) under various retry limit settings. Considering scalable video traffic delivery over the IEEE 802.11e WLANs, our study shows the importance of adaptiveness in retry limit settings for the unequal loss protection (ULP) design. Based on the study, we present a simple yet effective retry limit based ULP which adaptively adjusts the retry limit setting of the IEEE 802.11e medium access control protocol to maintain a strong loss protection for critical video traffic transmission. The simulation results illustrate significant advantages in the delivered video quality for our proposed design. 相似文献
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本文分析了信息在战争中不断增强的地位和侦察装备获取战场信息的发展概况,认为全维(全时空、全频谱)侦察网络是获取战场信息的主要途径,是未来信息化战争的物质基础。 相似文献