侧墙技术在相变存储器中的应用

从相变存储器(phase change random access memory,PCRAM)的基本结构和工作原理出发,首先介绍了PCRAM的技术优势、面临的技术挑战、常用的解决策略以及存在的相应问题;接着阐述了在微电子加工中广泛应用的关键工艺——侧墙技术,并将其在PCRAM中的应用成果进行了分类;然后从加热电极的制备、相变材料限制结构的制备、新相变材料的制备与表征和器件间互联等4个方面展开叙述;最后展望了该技术在相变存储领域应用发展的趋势。侧墙技术因其具备自对准的特点,制备工艺可控性好,制备精度不依赖于光刻精度,在纳米技术飞速发展的今天,侧墙技术将会在更高精度上发挥其作用。     

Redback SM480——专为以太网业务传送而优化的电信平台

以太网是一种用途非常广泛的技术。这种技术为人熟识,相对便宜,一向是建构接入汇聚网、城域网及传输所采用的首选技术。事实上,市面上已有多种以太网平台可供使用,其中有交换机或路由器形式的,也有两者之组合。当前建造新一代城域网的大趋势,迫使运营商为了竞争而必须要求设备供应商提供能满足特定条件的解决方案（某程度上这些条件可能是互相矛盾的）：     

A Pattern Recognition Method of Personalized Adaptive Learning in Online Education

Mobile Networks and Applications - In order to effectively identify the pattern of personalized adaptive learning in online education and improve the recommendation satisfaction of personalized...     

A fully integrated multi-band ED-mode pHEMT VCO using variable transformer and switched resonator

A systematic approach to the design of a reconfigurable LC-coupled voltage-controlled oscillator (VCO) is proposed in this article. The focus is on the choice of the reactive elements of the resonance tank which are most suitable to switch to the desired oscillation frequencies. The optimum Q of the tank will be determined by the selected component. We report a 0.5-µm enhancement–depletion (ED) mode pHEMT (HEMT, high-electron mobility transistor) multiple-frequency VCO, and the generation of multiple frequencies are achieved using switched resonator topology. LC-tank circuit is built by square transformers. By careful selection of the reactive elements, evenly distributed results showed at each designed band. The multi-band ED-mode pHEMT VCO showed the output power of ?4.7?dBm for 2?GHz band, ?6.67?dBm for 3.86?GHz band and ?5.9?dBm for 4.5?GHz band, respectively. The phase noises at 1?MHz offset frequency from carrier were ?112.8?dBc/Hz for 2?GHz, ?105?dBc/Hz for 3.86?GHz and ?103.3?dBc/Hz for 4.5?GHz, respectively. The total chip size is only 1.17?×?0.83?mm².     

First-principles investigation of the optical properties of CuIn(SxSe1–x)2

We optimized the lattice structure of sulfur-doped CuInSe₂ using first principles. The lattice constants for CuIn(S_xSe_1–x)₂ vary linearly with x according to a(x)=–0.02828x+0.58786 nm and c(x)=–0.05692x+1.1834 nm, which agree well with experimental data. The optical properties of CuIn(S_xSe_1–x)₂ were then systematically investigated using first-principles calculations with the HSE06 functional. We present data for the complex dielectric function, refractive index, extinction coefficient, reflectivity index, absorption coefficient, and optical bandgap for CuIn(S_xSe_1–x)₂. The optical bandgap E_g obtained from the absorption coefficient is 1.07 eV for CuInSe₂ and 1.384 eV for CuInS₂. These values are very close to experimental results, indicating that first-principles calculations can yield accurate bandgap values. The optical bandgap of CuIn(S_xSe_1–x)₂ increases linearly with the sulfur concentration according to E_g=0.3139x+1.0825 eV.     

宽带无线TDMA系统的自适应调制技术

无线多媒体业务的快速增长促进了宽带无线ＴＤＭＡ通信系统的研究和开发,宽带无线ＴＤＭＡ通信系统方面出现了一些新的技术和系统设计概念。讨论宽带无线ＴＤＭＡ系统中采用的自适应调制技术。     

激光直写中光刻胶对激光能量的吸收模型

光刻胶对激光能量的吸收模型是激光直写中的重要模型,它是进行邻近效应计算机模拟进而实现邻近校正不可缺少的重要依据。分析了影响光刻胶吸收激光束能量的主要因素,提出了一种光刻胶对激光能量的吸收模型。实验表明,该模型能更精确地表示光刻胶吸收激光能量密度分布的实际情况,能为激光直写邻近校正及微光学元件等光刻过程的计算机模拟提供可靠的依据。     

有源激光敌我识别系统作用距离仿真

分析了有源激光敌我识别系统组成和工作原理;在建立大气衰减模型基础上,利用高斯光束理论描述激光光束的传拎,从誓光峰值功率、束散角等参数推导出激光光束传输的理论模型,在考虑安装平台尺寸以及系统瞄准性能的前提下,对有源激光敌霉识别鎏鱼的佳用雌壹进行了仿真计算,计算结果表明最小作用距离对系统的限制较大,是设计激光敌我识别系统激...     

Growth of CdS Nanoneedles by Pulsed Laser Deposition

CdS nanoneedles have been grown on Ni-coated Si (100) substrates by pulsed laser deposition. Substrate temperature and Ni-catalyst layer thickness were found to have great effects on the density and morphology of the as-grown CdS nanoneedles. Crystalline CdS nanoneedles with middle diameter and length of about 40?nm to 100?nm and 400?nm to 1000?nm, respectively, could be obtained at 350°C to 450°C on Ni-coated silicon (100) substrates, and nanoneedles with good shapes were obtained at 400°C substrate temperature. From the cross-section morphologies, it was found that the CdS nanoneedles grew out of the base CdS crystallite layer with thickness of about 500?nm. Based on the experimental results, vapor?Csolid and vapor?Cliquid?Csolid growth modes describe the CdS nanoneedle growth.     

基于不同场景的县乡OTN网络扩容方案研究

目前OTN网络在县乡层面已得到大量部署和全面应用,但现开通的电路并不能满足未来大带宽的需求,基于此,对县乡层面OTN组网模式和业务需求进行了分析,结合主流厂家的常见设备,提出了适合县乡不同场景的OTN网络扩容解决方案,以期为构建高速、智能、安全且面向未来的本地传送网络的理论创新与实践工作提供借鉴。