Preparation of nanometer MgO by sol-gel auto-combustion

Nanometer MgO was prepared via a sol-gel auto-combustion technique using magnesium nitrate as raw material and citric acid as chelating agent. IR spectra of the dried gel were used to investigate the structure of the precursors. By studying the different TG curves of magnesium citrate gel prepared by different methods, we found that a combustion process occurred and the nitrate ions acted as an oxidant in the combustion process. TEM photographs of synthesized powders from the sol-gel auto-combustion showed that the crystallites were uniform in size. In addition, the XRD pattern of this sample showed that the particle size was 8.9 nm. The BET curves, in turn, showed that the specific surface of the sample was 26.34 m²/g. The mechanism of the frothing process in restraining agglomeration is discussed. __________ Translated from Journal of East China Normal University (Natural Science), 2007, (2): 52–57 [译自: 华东师范大学学报(自然科学版)]     

Indentation responses of piezoelectric films

Frictionless indentation responses of transversely isotropic piezoelectric film/rigid substrate systems under circular cylindrical indenter (i.e., punch), conical indenter (i.e., cone), and spherical indenter (i.e., sphere) are investigated. Both insulating and conducting indenters are considered. The technique of Hankel transformation is employed to derive the corresponding dual integral equations for the mixed boundary value indentation problems. For the two limiting cases of infinitely thick and infinitely thin piezoelectric films, closed-form solutions are obtained. For piezoelectric films of finite thickness, a numerical method is constructed to solve the dual integral equations and semi-empirical models having only two unknown parameters are proposed for the responses of indentation force, electric charge and electric potential, and contact radius. With the two parameters inferred from the numerical results, the semi-empirical formulae are found to provide good estimates of the indentation responses for the two limiting cases of infinitely thick and thin piezoelectric films, as well as those in between. The inferred parameters in the proposed semi-empirical formulae for normalized indentation force and electric charge are checked against four different piezoelectric materials and are found to be insensitive to the selection of piezoelectric materials. It is believed that the proposed semi-empirical indentation formulae are useful in developing experimental indentation techniques to extract the material properties of piezoelectric films.     

A 16-Mb MRAM featuring bootstrapped write drivers

A 16-Mb magnetic random access memory (MRAM) is demonstrated in 0.18-/spl mu/m three-Cu-level CMOS with a three-level MRAM process adder. The chip, the highest density MRAM reported to date, utilizes a 1.42/spl mu/m/sup 2/ 1-transistor 1-magnetic tunnel junction (1T1MTJ) cell, measures 79 mm/sup 2/ and features a /spl times/16 asynchronous SRAM-like interface. The paper describes the cell, architecture, and circuit techniques unique to multi-Mb MRAM design, including a novel bootstrapped write driver circuit. Hardware results are presented.     

企业信息化中的网络存储整合应用

首先介绍了网络存储技术中NAS技术和SAN技术的基本原理,并对两者的特性进行了比较;然后详细介绍了企业信息化过程中网络存储整合的一个典型案例,分析了其整合前存在的不足,制定有效的整合实施方案,并对实施过程中许多关键技术部分进行了阐述,最终很好的达到了预定目标;最后总结了网络存储整合需要规划多种技术相融合的必要性.     

Miniature InGaAsP/InP phase modulator for integrated opto-electronics

Miniature, etching ridge InGaAsP/InP Phase Modulator with highly efficient phase shifting efficiency of 60°/V.mm and 43°/V.mm for TE and TM modes, respectively, and 3 dB bandwidth of 650 MHz at 1.52 μm are reported. It is well suited for integrated opto-electronics. Some functions depending on bandwidth of the devices are discussed.     

LB技术制备大面积超薄PMMA抗蚀层的研究

采用自行研制的ＬＢ自动提膜装置，制备出大面积（１０×８ｃｍ２）、高质量的ＰＭＭＡ超薄抗蚀剂膜，并将其用于高分辨率铬掩模版的研制。通过电子束曝光，湿法蚀刻，制作了分辨率优于０．５μｍ，特征线宽０．３８μｍ的４（１００ｍｍ）铬掩模版。     

用于红外地平仪的双列硅集成热堆传感器

本文报道了试用于红外地平仪的新型热堆传感器。由于尺寸小、集成热偶对数高,故设计成双列硅集成结构,集成B-Sb热偶对为112对。采用集成电路工艺和微细加工技术研制,使器件获得较好的稳定性和可靠性。测得器件性能为:电阻10±1kΩ,响应率0.9～1.2V/W,时间常数<100ms.探测率D~*≈1×10~8cmHz~(1/2)/W。     

基于公共存储器进行数据交换的高速数字图象处理系统

本文介绍了一种基于公共存储器进行数据交换的高速数字图象处理系统．给出了公共存储器的设计，描述了处理器对公共存储器的进程同步控制．     

The Cubooctahedron Shape──A Suboptimal Cell Shape for 3－Dimensional Cellular System

ＴｈｅＣｕｂｏｏｃｔａｈｅｄｒｏｎＳｈａｐｅ──ＡＳｕｂｏｐｔｉｍａｌＣｅｌｌＳｈａｐｅｆｏｒ３－ＤｉｍｅｎｓｉｏｎａｌＣｅｌｌｕｌａｒＳｙｓｔｅｍＣｈａＧｕａｎｇｍｉｎｇ；ＬｉＺｈｅｎｇｍａｏ；ＬｕＦａｎ（ＵｎｉｖｅｒｓｉｔｙｏｆＥｌｅｃｔｒｏｎｉ...     

Closed-form physical model for VLSI bipolar devices consideringenergy transport

A closed-form physical model is reported for VLSI bipolar devices considering energy transport. Based on the model, for a base width of 810 Å, the bipolar device, biased at V_cb=2 V, has a peak electron temperature of over 700 K, which results in a 5% reduction in the collector current