相变存储器存储单元瞬态电流测量

介绍了相变存储单元瞬态电流的测量方法。根据相变存储器的工作特性,利用微弱电流取样电阻测量法,合理选择测量参数测得了相变存储单元的瞬态电流,电阻与电流关系特性曲线和动态电阻。并根据测量电路等效电路模型分析影响测量的因素,估算出电路中的分布电容。     

丁苯橡胶装置干燥系统的技术改造

通过对干燥系统原有流程的节能、扩能优化改造 ,使装置达到年产 130kt丁苯橡胶的生产能力 ,蒸汽单耗降低了 0 .2 4t ,同时为扩建改造节省了大量投资 ,效益显著     

CIGS Thin Films for Cd-Free Solar Cells by One-Step Sputtering Process

Cu(In_1?x Ga _x )Se₂ (CIGS) thin films were deposited by a one-step radio frequency (RF) magnetron sputtering process using a quaternary CIGS target. The influence of substrate temperature on the composition, structure, and optical properties of the CIGS films was investigated. All the CIGS films exhibited the chalcopyrite structure with a preferential orientation along the (112) direction. The CIGS film deposited at 623 K showed significant improvement in film crystallinity and surface morphology compared to films deposited at 523 and 573 K. To simplify the manufacturing procedure of solar cells and avoid the use of the toxic element Cd, the properties of ZnS films prepared by RF sputtering were also investigated. The results revealed that the sputtered ZnS film exhibits good lattice matching with the sputtered CIGS film with significantly lower optical absorption loss. Finally, all-sputtered Cd-free CIGS-based heterojunction solar cells with the structure SLG/Mo/CIGS/ZnS/AZO/Al grids were fabricated without post-selenization. Furthermore, the results demonstrated the feasibility of using a full sputtering process for the fabrication of Cd-free CIGS-based solar cell.     

Effect of Heat Treatments on the Structural and Magnetic Properties of La-Co Substituted Strontium Ferrite Films

A sputter-deposited strontium ferrite film with perpendicular anisotropy has been developed. The film, composed of La_0.33Sr_0.67Co_0.25Fe_11.75O₁₉, has been fabricated directly on quartz glass substrates by radio frequency magnetron sputtering with various heat treatments. The structural and magnetic property dependence of those films on heat treatments has also been studied. The optimized condition is the heat treatment of in situ heating at 400°C and post-annealing at 850°C–900°C. When post-annealing temperature exceeds 900°C, parasitic phases of γ-Fe₂O₃ and LaFeO₃ appear and gradually increase; meanwhile, the magneto plumbite phase gradually decreases. High c-axis perpendicularly oriented films with the coercivity (4148 Oe), remanence squareness ratio (0.89) and perpendicular magnetic anisotropy energy density (1.65 × 10⁶ erg/cm³) are achieved, which is attributed to the single magneto plumbite phase with compact platelet grains and almost complete (0 0 l) texture of the c-axis normal to the film plane.     

Investigation into Texture,Preferential Orientation,and Optical Properties of Zinc Oxide Nanopolycrystalline Thin Films Deposited by the Sol–Gel Technique on Different Substrates

ZnO nanopolycrystalline thin films were deposited by the sol–gel technique on glass and silicon, and compared systematically via atomic force microscopy, scanning electron microscopy, x-ray diffraction, UV–Vis spectrophotometry, and fluorescence spectrophotometry. The thickness of the ZnO films was measured by ellipsometric microscopy. A higher preheating temperature was needed to obtain films with a strong preferential orientation. The optimal annealing temperatures for c-axis films on glass and silicon substrates were 525°C and 750°C, respectively. The relative intensity of the blue–green emission peak tends to increase with the annealing temperature. When the film is annealed in N₂, the transmittance of the film reduces while the intensity of the blue–green emission increases.     

磁光盘的介质膜材料AlN,AlSiN薄膜的电子显微分析

本文研究了磁光盘介质薄膜－ＡｌＮ和ＡｌＳｉＮ薄膜的电子显微结构，通过透射电镜分析了ＡｌＮ薄膜的多晶结构和ｃ轴垂直取向；通过Ｘ射线衍射分析、透射电镜分析和Ｘ射线光电子能谱分析，确定了ＡｌＳｉＮ薄膜并不是多晶ＡｌＮ和ＳｉＮ薄膜的简单组合，而是形成了稳定的非晶特征结构。且ＡｌＳｉＮ薄膜由于其非晶结构而比ＡｌＮ薄膜的磁光克尔效应增强效果更优越。     

Microscopic mechanism of imprint in hafnium oxide-based ferroelectrics

Hafnia-based ferroelectrics have greatly revived the field of ferroelectric memory(FeRAM),but certain reliability issues must be satisfactorily resolved before ...     

Magnetic Moments in SmCo5 and SmCo5?x Cu x Films

SmCo₅ is an emerging perpendicular magnetic material for super-high density magnetic recording, due to its large magnetic anisotropy energy. In this paper, the magnetic moments of SmCo_5?x Cu _x have been studied using first principles calculation based on density-functional theory (DFT). Calculations are performed using the pseudopotential plane wave DFT code Vienna ab initio simulation package (VASP) with the projector augmented wave (PAW) method. The local density approximation LDA+U method is used for the calculation of the exchange correlation energy of Sm. The calculation results show that the average Co magnetic moment of SmCo_5?x Cu _x decreases with the increase of Cu doping concentrations, and the influence of the Cu doping on the spin state of Co is greater than that of Sm. The magnetic anisotropy energy of SmCo₅ is analyzed. The electronic density of states and the differential in spin densities of atoms show that the spatial distribution of 4f electron and the 4f?C3d coupling are the controlling factors of the magnetic anisotropy energy of SmCo₅.     

RE－TM磁光记录薄膜的磁场电效应研究

研究了磁性薄膜磁场电效应的测试方法，ＲＥ－ＴＭ磁光薄膜的测试样品制备、样品的磁场电效应（霍尔效应和磁阻效应）及其温度特性。实验结果表明，制备的ＴｂＦｅＣＯ薄膜的补偿点约为─３８℃。