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951.
952.
Tzung-Lin Li Wu-Lin Ho Hung-Bin Chen Wang H.C.-H. Chun-Yen Chang Chenming Hu 《Electron Devices, IEEE Transactions on》2006,53(6):1420-1426
A novel dual-metal gate technology that uses a combination of Mo-MoSi/sub x/ gate electrodes is proposed. An amorphous-Si/Mo stack was fabricated as a gate electrode for the n-channel device. It was thermally annealed to form MoSi/sub x/. Pure Mo served as the gate electrode for the p-channel device. The work functions of MoSi/sub x/ and pure Mo gates on SiO/sub 2/ are 4.38 and 4.94 eV, respectively, which are appropriate for devices with advanced transistor structures. The small increase in the work function (< 20 meV) and the negligible equivalent oxide thickness variation (< 0.08 nm) after rapid thermal annealing at 950 /spl deg/C for 30 s also demonstrate the excellent thermal stabilities of Mo and MoSi/sub x/ on SiO/sub 2/. Additional arsenic ion implantation prior to silicidation was demonstrated further to lower the work function of MoSi/sub x/ to 4.07 eV. This approach for modulating the work function makes the proposed combination of Mo-MoSi/sub x/ gate electrodes appropriate for conventional bulk devices. The developed dual-metal-gate technology on HfO/sub 2/ gate dielectric was also evaluated. The effective work functions of pure Mo and undoped MoSi/sub x/ gates on HfO/sub 2/ are 4.89 and 4.34 eV, respectively. A considerable work-function shift was observed on the high-/spl kappa/ gate dielectric. The effect of arsenic preimplantation upon the work function of the metal silicide on HfO/sub 2/ was also demonstrated, even though the range of modulation was a little reduced. 相似文献
953.
A.W.M. Lee B.S. Williams S. Kumar Qing Hu J.L. Reno 《Photonics Technology Letters, IEEE》2006,18(13):1415-1417
We report the use of a /spl sim/50-mW peak power 4.3-THz quantum cascade laser (QCL) as an illumination source for real-time imaging with a 320 /spl times/ 240 element room-temperature microbolometer focal-plane array detector. The QCL is modulated synchronously with the focal-plane array for differential imaging. Signal-to-noise ratios of /spl sim/340 are achieved at a 20-frame/s acquisition rate, and the optical noise equivalent power of the detector array at 4.3 THz is estimated to be /spl sim/320 pW//spl radic/Hz. Both reflection and transmission mode imaging are demonstrated. 相似文献
954.
This paper simulates a kind of new sub-50 nm n-type double gate MOS nanotransistors by solving coupled Poisson-Schrödinger equations in a self-consistent manner with a finite element method, and presents a systematic simulation-based study on quantum-mechanical effects, gate leakage current of FinFETs. The simulation results indicate that the deviation from the classical model becomes more important as the gate oxide, gate length and Fin channel width becomes thinner and the Fin channel doping increases. Gate tunneling current density reduces with the body thickness decreasing. Excessive scaling increases the gate current below Fin thickness of 5 nm. The gate current can be dramatically reduced beyond 1017 cm−3 with the Fin body doping increasing. In order to understand the influence of electron confinement, quantum mechanical simulation results are also compared with the results from the classical approach. Our simulation results indicate that quantum mechanical simulation is essential for the realistic optimization of the FinFET structure. 相似文献
955.
M.H. Hu Hong Ky Nguyen Kechang Song Yabo Li N.J. Visovsky Xingsheng Liu N. Nishiyama S. Coleman L.C. Hughes Jr. J. Gollier W. Miller R. Bhat Chung-En Zah 《Photonics Technology Letters, IEEE》2006,18(4):616-618
We report on the static and dynamic performance of high-power and high-modulation-speed 1060-nm distributed Bragg reflector (DBR) lasers for green-light emission by second-harmonic generation. Single-wavelength power of 387 mW at 1060-nm wavelength and green power as high as 99.5 mW were achieved. A thermally induced wavelength tuning of 2.4 nm and a carrier-induced wavelength tuning of -0.85 nm were obtained by injecting current into the DBR section. Measured rise-fall times of 0.2 ns for direct intensity modulation and 0.6 ns for wavelength modulation make the lasers suitable for >50-MHz green-light modulation applications. 相似文献
956.
介绍PowerPoint2003中内、外部声音的运用与控制技术. 相似文献
957.
958.
本文讨论了分布式环境下报表超级汇总处理系统的特点、总体结构及处理流程,提出了一个基于Internet和Borland公司MIDAS技术的远程提交报表数据的方法,设计并实现了一个分布式超级汇总报表处理系统SRAFT,该系统由四个子系统组成:基于C/S结构的报表制度设计器、基于C/S结构的报表数据处理器、基于MIDAS技术的远程提交数据系统和基于B/S结构的报表数据查询与发布系统。 相似文献
959.
采用逆转录-聚合酶链式反应(RT-PCR)方法,从鲤鱼脑垂体获得了两种GtH β亚基的cDNA, 克隆在pMD18-T载体.经测序确证后,将这两个基因克隆到原核表达载体pET -32(a)中,转化E.coli表达菌BL21(DE3),以IPTG诱导融合蛋白的高效表达.利用初步纯化后的抗原免疫新西兰大白兔,制备多克隆抗体.应用制备的兔抗血清与抽提的鲤鱼脑垂体的总蛋白分别进行Western-blot及ELISA分析,结果显示获得的多抗能特异识别各自的天然蛋白.该结果为纯化天然GtH蛋白提供了有效的检测手段,为进一步制备GtH单克隆抗体奠定了基础. 相似文献
960.
针对钢筋混凝土高耸构筑物爆破拆除出现问题较多的情况,建立了钢筋混凝土高耸构筑物定向倒塌的力学模型,提出在计算爆破切口角度时,应计入被炸裸露钢筋的支撑力。从钢结构的设计理论出发,提出了爆破切口高度计算的新方法。对某工程进行了验算,计算结果与实际采用爆破参数吻合,对钢筋混凝土高耸构筑物爆破拆除设计具有指导意义。 相似文献