Low-resistance polysilicon process in contact application for high density devices

For the lowest resistance, it is required to have the epitaxial silicon contact between the silicon plug and the substrate and good step coverage at the high aspect-ratio contact holes, simultaneously. In this work, a double polysilicon (DPS) deposition technique was proposed for the requirements. The first, thin silicon layer is deposited in a single-wafer process chamber with an in-situ H₂-RTP (rapid thermal process) treatment for the epitaxial contact, and the second silicon layer is formed in a batch-type furnace for good step coverage. From chain resistance, Kelvin R_c, and current-voltage (I–V) measurement, the DPS process meets both low resistance and good uniformity, so that it suggests a breakthrough in the small-sized, semiconductor device application.     

矿山数字化摄影测量系统的设计与实现

本文主要阐述矿山数字化摄影测量的基本原理、方法、矿山数字化摄影系统的硬件配置及软件组成，扼要介绍了系统所采用的算法及相关技术。     

DPS数据处理软件在发酵培养基优化中的应用

在发酵工业中,发酵培养基的优化对发酵水平的提高具有非常重要的作用。DPS(Data Processing System)是一款强有力的数据处理软件,兼具多种类型的试验设计技术以及齐全的统计分析功能。文中介绍了DPS数据处理软件在发酵培养基优化中的具体实施方法和步骤,运用该软件对试验结果进行处理,结果表明,DPS数据处理软件能简单且有效地对发酵培养基进行优化。     

MIMO信道中衰落信号的多谱勒功率谱

MIMO系统中的角度功率谱有多种分布形式,所以经典多普勒功率谱不再适用。针对常用的均匀分布、余弦分布、高斯分布和拉氏分布的入射波角度功率谱,分别推导了多谱勒功率谱解析式。通过仿真比较了不同角度功率谱下的多普勒功率谱,并分析各种参数对其的影响。这些工作对MIMO信道中频率扩散的刻画做了拓展。     

<Emphasis Type="Bold">Development of Divisional Parallel Scan Technology in Large-Scale Laminated Object Manufacturing</Emphasis>

Many technological difficulties exist in the field of rapid prototyping (RP) technology when making large-scale prototypes. The manufacturing efficiency is the main problem, and the process implemention and RP equipment also present difficulties. In this paper, the concept of divisional parallel scan is presented. Laminated object manufacturing (LOM) technology is used for the basic forming process and has been improved continuously through practice. Static divisional scan technology was also better developed to dynamic divisional scan technology, which can help in achieving the object of improving work efficiency and optimising design.     

Modal analysis of the microwave frequency response and composite right‐/left‐handed operation of a rectangular waveguide loaded with double positive and double negative materials

This article presents a theoretical study of the electromagnetic wave propagation in a rectangular waveguide, loaded with double positive (DPS) and double negative (DNG) dielectrics. The frequency response of the waveguide is analyzed using a modal technique. The results show that when at least one of the dielectrics is a DNG material the cutoff frequency of the waveguide is much more lower than the cutoff frequency of the DPS loaded or the empty waveguide. This interesting property means that very low frequency signals could be guided by structures that have very small size. Properties of composite right‐ and left‐handed wave propagation are also observed as well as the characteristic stop‐band between the frequency regions in which RH and LH wave propagation occurs. © 2007 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2007.     

A proteomic analysis of green and white sturgeon larvae exposed to heat stress and selenium

Temperature and selenium are two environmental parameters that potentially affect reproduction and stock recruitment of sturgeon in the San Francisco Bay/Delta Estuary. To identify proteins whose expression is modified by these environmental stressors, we performed a proteomic analysis on larval green and white sturgeons exposed to 18 or 26 °C and micro-injected with Seleno-L-Methionine to reach 8 µg g⁻¹ selenium body burden, with L-Methionine as a control. Selenium and high temperature induced mortalities and abnormal morphologies in both species, with a higher mortality in green sturgeon. Larval proteins were separated by two-dimensional gel electrophoresis and differential abundances were detected following spot quantitation and hierarchical cluster analysis. In green sturgeon, 34 of 551 protein spots detected on gels showed a variation in abundance whereas in white sturgeon only 9 of 580 protein spots were differentially expressed (P < 0.01). Gel replicates were first grouped according to heat treatment. Fifteen of these spots were identified using MALDI TOF/TOF mass spectrometry. Proteins involved in protein folding, protein synthesis, protein degradation, ATP supply and structural proteins changed in abundance in response to heat and/or selenium. 40S ribosomal protein SA, FK506-binding protein 10, 65 kDa regulatory subunit A of protein phosphatase 2, protein disulfide isomerase, stress-induced-phosphoprotein 1, suppression of tumorigenicity 13 and collagen type II alpha 1, were differentially expressed in high temperature treatment only. Serine/arginine repetitive matrix protein 1, creatine kinase, serine peptidase inhibitor Kazal type 5 and HSP90 were sensitive to combined temperature and selenium exposure. Valosin-containing protein, a protein involved in aggresome formation and in protein quality control decreased more than 50% in response to selenium treatment. Potential use of such proteins as biomarkers of environmental stressors in larval sturgeons could indicate early warning signals preceding population decline.     

冶金企业谐波分析仪系统的研究

介绍基于TMS320VC5509A的冶金企业谐波分析仪系统的研究,并根据工业现场数据传输的要求,选出谐波分析仪合适的以太网数据传输方式,实现了冶金企业对生产设备谐波监测的要求。     

煤炭生物絮凝絮体分形试验研究

为解决化工产品类絮凝剂的大量使用会对环境造成严重污染的问题,采用对煤炭具有良好絮凝作用的枯草芽孢杆菌作为生物絮凝剂产生菌,开展煤炭生物絮凝试验和絮体分形试验研究。通过对生物絮凝的絮体进行显微图像采集与分析,利用絮凝体的投影面积与最大长度的函数关系计算絮凝体的分形维数。研究发现,枯草芽孢杆菌絮凝剂用量和絮体分形维数与煤泥水透光率之间具有显著的相关性。研究结果表明,以絮凝体分形维数为主控指标,可以实现对枯草芽孢杆菌絮凝剂的定量控制,能够比较客观地反映煤泥水的絮凝沉降过程。     

FPGA芯片内数字时钟管理器的设计与实现

在FPGA芯片内,数字时钟管理器(DCM)不可或缺,DCM主要完成去时钟偏移、频率综合和相位调整的功能,其分别由延迟锁相环(DLL)、数字频率合成器(DFS)以及数字相移器(DPS)三个模块来实现。对这三个模块的原理及设计进行了详细地阐述,并给出了仿真结果,该DCM电路通过了0.13μm工艺流片。测试结果表明,在低频模式下,该DCM能工作在24～230 MHz之间;在高频模式下,该DCM能工作在48～450 MHz之间,其输入及输出抖动容忍度在低频模式下能达到300 ps,在高频模式下能达到150 ps。