一种Xilinx FPGA有效配置位保护方法

机载电子设备中广泛采用的静态随机存储器(Static Random Access Memory, SRAM)型现场可编程门阵列(Field Programmable Gate Array, FPGA)易受到大气中子辐射的影响而发生单粒子翻转。为了提高抗干扰能力,针对SRAM型FPGA需要进行抗单粒子翻转防护,提出了一种Xilinx FPGA有效配置位的保护方法。该方法提取电路中的有效配置位,纠错电路检测到电路中发生单粒子翻转时,纠正有效配置位上发生的翻转。实验表明该方法可以有效保护Xilinx FPGA的有效配置位并提高了纠错电路的效率。     

基于SRAM型FPGA单粒子效应的故障传播模型

SRAM型FPGA在辐射环境中易受到单粒子翻转的影响,造成电路功能失效.本文基于图论和元胞自动机模型,提出了一种针对SRAM型FPGA单粒子效应的电路故障传播模型.本文将单粒子翻转分为单位翻转和多位翻转来研究,因为多位翻转模型还涉及到了冲突处理的问题.本文主要改进了耦合度的计算方式,通过计算FPGA布局布线中的相关配置位,从而使得仿真的电路故障传播模型更接近于实际电路码点翻转的结果,与以往只计算LUT相关配置位的方法比较,平均优化程度为19.89%.最后阐述了本模型在故障防御方面的一些应用,如找出最易导致故障扩散的元胞.     

超大规模FPGA的单粒子效应脉冲激光测试方法

建立了一种28 nm HPL硅工艺超大规模SRAM型FPGA的单粒子效应测试方法。采用静态测试与动态测试相结合的方式,通过ps级脉冲激光模拟辐照实验,对超大规模FPGA进行单粒子效应测试。对实验所用FPGA的各敏感单元(包括块随机读取存储器、可配置逻辑单元、可配置存储器)的单粒子闩锁效应和单粒子翻转极性进行了研究。实验结果证明了测试方法的有效性,揭示了多种单粒子闩锁效应的电流变化模式,得出了各单元的单粒子效应敏感性区别。针对块随机读取存储器、可配置逻辑单元中单粒子效应翻转极性的差异问题,从电路结构方面进行了机理分析。     

基于FPGA定时刷新控制单元的应用技术研究

SRAM型FPGA在航天领域有着广泛的应用,为解决FPGA在宇宙环境中单粒子翻转的问题,适应空间应用需求,给出了一种低成本抗辐照解决方案,对耐辐射FPGA器件进行抗单粒子翻转加固设计。该方案兼容多种型号FPGA芯片,从3片SPI FLASH中读取配置数据,通过串行接口配置FPGA,并在配置完成后按照设定时间周期性刷新芯片,可以满足航天领域对抗辐照型FPGA的使用需求。     

一种静态随机存储器型现场可编程门阵列的单粒子软错误率的软件分析方法

静态随机存取存储器(SRAM)型现场可编程门阵列(FPGA)在当前空间电子设备中取得了广泛的应用,尽管它对空间辐射引起的单粒子翻转效应极其敏感。在FPGA的配置存储器中发生的单粒子翻转造成的失效机理不同于传统的存储器中的单粒子翻转。因此,如何评价这些单粒子翻转对系统造成的影响就成了一个值得研究的问题。传统的方法主要分为辐照实验和故障注入两种技术途径。本文中提出了一种新的方法,可以用来分析单粒子翻转对构建在FPGA上的系统造成的影响。这种方法基于对FPGA底层结构以及单粒子翻转带来的失效机理的深入理解,从布局布线之后的网表文件出发,寻找所有可能破坏电路结构的关键逻辑节点和路径。然后通过查询可配置资源与相应的配置数据之间关系来确定所有敏感的配置位。我们用加速器辐照实验和传统的故障注入方法验证了这种新方法的有效性。     

Virtex FPGA抗单粒子翻转技术

SRAM型FPGA开发过程灵活,在航天领域有广泛的应用,但该系列FPGA易发生单粒子翻转事件,导致功能中断或信息丢失。配置刷新结合三模冗余能有效抑制单粒子翻转带来的影响。在详细讨论了配置刷新+三模冗余的基础上,提出了FPGA自主刷新+三模冗余的解决方案,保证FPGA抗单粒子性能的基础上提高了系统的资源利用率,经注错试验验证了方案可行性。     

SRAM型FPGA单粒子翻转测试及加固技术研究

SRAM型FPGA空间应用日益增多,只有针对其特点设计相应的单粒子试验的测试程序才能系统、准确地获取该类芯片的单粒子翻转特性,为抗辐射加固设计提供依据.阐述了单粒子翻转的静态和动态的测试方法.静态测试包括硬件设计和配置位回读程序的设计;动态测试主要针对CLB(配置逻辑单元)和BRAM(块存储器)两部分进行了相应的软件测...     

模拟低空环境下FPGA的SEU测试系统结果分析

为了探究在低空环境下SRAM型FPGA产生单粒子翻转事件与大气中高能粒子剂量的关系,设计了一种便携式测试系统。使用该系统在某地6个不同海拔的测试点对SRAM型FPGA进行单粒子翻转测试。某地平均海拔在3000～5000 m,可以很好地模拟低空飞行环境。通过测试试验,该系统获得了大量现场数据,使用Matlab对测试数据进行了分析。结合在某地的测试结果,从SRAM型FPGA的存储结构、单粒子翻转产生机理、测试系统的工作原理等方面入手,对该测试系统的科学性与实用性进行了验证分析。分析结果表明,该便携式测试系统科学有效,可为航空航天领域中SRAM型FPGA的选型与使用提供一种参考方式。     

基于FPGA芯片的抗单粒子翻转的动态刷新技术研究

在分析FPGA空间单粒子效应的基础上,为了实现星载电子设备运行的稳定性,研究FPGA的动态刷新原理,介绍了几种抗单粒子翻转方法,根据位流文件设计出用于动态刷新的指令并通过实例验证。通过FPGA定期从PROM中读取用户配置信息,动态刷新内部配置信息,从而减少FPGA配置存储器发生单粒子翻转的概率,提高星载电子设备运行的可靠性。     

Virtex-Ⅱ系列FPGA的回读与部分重配置

介绍了基于SRAM的Virtex-Ⅱ系列FPGA试验样板的系统功能,实现了对XQ2V3000FPGA的回读与部分重配置,并给出了JTAG接口下的时序,最后分析了试验的结果。结果表明,FPGA回读可以有效地检测FPGA是否发生了单粒子翻转,而部分重配置可以有效地降低FPGA发生翻转的累积效应,并修复系统功能。     

Technology innovation and process integrations for sub-100nm gate patterning

This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration.     

White organic light-emitting devices based on fac tris（2- phenylpyridine） iridium sensitized 5,6,11,12-tetraphenylnap -hthacene

We have fabricated the white organic light-emitting devices （WOLEDs） based on 4,4＇ -bis（2,2 -diphenyl vinyl）-1,1＇ - biphenyl （DPVBi） and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene （rubrene）. The device structure is ITO/2T-NATA （20 nm）/NPBX （20 nm）/CBP： x%Ir（ppy）3：0.5% rubrene （8 nm）/NPBX （5 nm）/DPVBi （30 nm）/Alq（30 nm）/LiF（0.5 nm）/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris （2-phenylpyridine） iridium [Ir（ppy）3], acts as a yellow light-emitting layer, and N,N＇ -bis- （1-naphthyl）- N,N＇ -diphenyl -1, 1＇ -biphenyl-4,4＇ -diamine （NPBX） acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir （PPY）3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V.     

Complete approach to automatic identification and subpixel center location for ellipse feature

To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction.     

小角度扩展相关性近似算法分析

本论文提出一种在多天线MIMO信道相关性建模中小角度扩展近似理论算法,并应用于分析MIMO系统性能。分析中分别对三种不同角能量分布情况下的空间相关性研发快速近似计算法,并同时提出双模(Bi-Modal)角能量分布情况下的近似运算。通过分析这些新方法的近似效率,可以得到计算简单、复杂度低、而且符合实际的MIMO相关信道矩阵,对系统级的快速高效计算法的研究和系统级的评估以及误差分析具有重要的意义。     

Curved crystal spectrometer for the measurement of X-ray lines from laser-produced plasmas

In order to diagnose the laser-produced plasmas, a focusing curved crystal spectrometer has been developed for measuring the X-ray lines radiated from a laser-produced plasmas. The design is based on the fact that the ray emitted from a source located at one focus of an ellipse will converge on the other focus by the reflection of the elliptical surface. The focal length and the eccentricity of the ellipse are 1350 mm and 0.9586, respectively. The spectrometer can be used to measure the X- ray lines in the wavelength range of 0.2-0.37 nm, and a LiF crystal （200） （2d = 0.4027 nm） is used as dispersive element covering Bragg angle from 30° to 67.5°. The spectrometer was tested on Shengnang- Ⅱ which can deliver laser energy of 60-80 J/pulse and the laser wavelength is 0.35 μm. Photographs of spectra including the 1 s2p ^1P1-1s^2 ^1S0 resonance line（w）, the 1s2p ^3P2-1s^2 1S0 magnetic quadrupole line（x）, the 1s2p ^3P1-1 s^2 ^1S0 intercombination lines（y）, the 1 s2p ^3S~1-1 s^2 ^1S0 forbidden line（z） in helium-like Ti Ⅹ Ⅺ and the 1 s2s2p ^2P3/2-1 s622s ^2S1/2 line（q） in lithium-like Ti Ⅹ Ⅹhave been recorded with a X-ray CCD camera. The experimental result shows that the wavelength resolution（λ/△ 2） is above 1000 and the elliptical crystal spectrometer is suitable for X-ray spectroscopy.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.     

A Versatile Mixed-Signal Pin Approach for Cost-Effective Test of Automotive ICs

Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V.     

Electronic Structure of Semiconductor Nanocrystals

This paper reviews our recent development of the use of the large-scale pseudopotential method to calculate the electronic structure of semiconductor nanocrystals, such as quantum dots and wires, which often contain tens of thousands of atoms. The calculated size-dependent exciton energies and absorption spectra of quantum dots and wires are in good agreement with experiments. We show that the electronic structure of a nanocrystal can be tuned not only by its size,but also by its shape. Finally,we show that defect properties in quantum dots can be significantly different from those in bulk semiconductors.     

Critical Stage Rule-Based Real Time Dispatch（RTD）System in Highly-Mixed-Products （HMP） FAB

An improving utilization and efficiency of critical equipments in semiconductor wafer fabrication facilities are concerned. Semiconductor manufacturing FAB is one of the most complicated and cost sensitive environments. A good dispatching tool will make big difference in equipment utilization and FAB output as a whole. The equipment in this paper is In-Line DUV Scanner. There are many factors impacting utilization and output on this equipment group. In HMP environment one of the issues is changing of reticule in this area and idle counts due to load unbalance between equipments. Here we'll introduce a rule-based RTD system which aiming at decreasing the number of recipe change and idle counts among a group of scanner equipment in a high-mixed-products FAB.     

Optical vibration and deviation measurement of rotating machine parts

It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer （LDV）.