检索结果-南通市图书馆

High-precision measurement of low reflectivity specular object based on phase measuring deflectometry

在线全文

学校读者我要写书评

暂无评论

光电工程 2017年第8期44卷 772-780页

作者： Yuxiang Wu Huimin Yue Yong Liu State Key Laboratory of Electronic thin films and Integrated devices School of Optoelectronic Information University of Electronic Science and Technology of China

Phase measuring deflectometry(PMD)is a robust,noncoherent technique for the characterization of specular *** measuring high specular reflectivity surface,PMD can deliver micron radian range local ***,when the measured surface has low specular reflectivity,the accuracy of the measured gradient is low since the captured fringe pattern shows low signal to noise *** phase error characteristics in PMD system when testing low reflectivity surfaces are *** analysis illustrates that the random phase error increases rapidly while the nonlinear error drops slowly with the decreasing of the tested surface *** order to attain high precision measurement of low reflectivity specular surface,a robust error reduction method based on wavelet de-noising is proposed to reduce the phase *** error reduction method is compared with several other normally used methods in both simulation and experiment *** method based on the wavelet de-noising shows better performance when measuring the low reflectivity specular surface.

关键词：光电工程电学技术测试调整

OBSERVATION ON DEFECTS IN POLYCRYSTALLINE SILICON thin filmS

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 295-299页

作者： Y.F. Hu1), H. Shen2), L. Wang3), Z.C. Liang3), Z.Y. Liu1) and L.S. Wen1) 1) College of Mechanical Engineering, South china university of Technology, Guan gzhou 510640, china 2) The School of Physics and Engineering, Zhongshan university, Guangzhou 510275 , china 3) Guangzhou institute of Energy Conversion, The Chinese Academy of Sciences, G uangzhou 510640, china College of Mechanical Engineering South China University of Technology Guangzhou 510640China The School of Physics and Engineering Zhongshan University Guangzhou 510275China Guangzhou institute of Energy Conversion The Chinese Academy of Sciences Guangzhou 510640China

Polycrystalline silicon thin films were prepared by RTCVD (rapid thermal chemica l vapor deposition) method on several substrates such as SSP (silicon sheet from powder) ribbon, poly-Si wafer and mono-Si wafer. Intra-granular defects such as stacking faults, twins and microstructure defects were investigated on thin fil ms by scan electron microscopy (SEM) technique.

关键词： poly-Si thin film intra-granular defects surface cross-section

High frequency performance of nano-scale ultra-thin-body Schottky-barrier n-MOSFETs

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2011年第8期54卷 1756-1761页

作者： DU Gang,LIU XiaoYan & HAN RuQi institute of Microelectronics,Peking university,Beijing 100871,china 1. institute of Microelectronics Peking University Beijing 100871 China

The high frequency performances of nano-scale ultra-thin-body (UTB) Schottky-barrier n-MOSFETs (SB-nMOSFETs) are investigated using 2D full-band self-consistent ensemble Monte Carlo method. The UTB SB-nMOSFET devices offer excellent RF performance with high values of f T and f *** significant dependence of f T and f max on gate voltage and weak dependence on barrier height are ***,the significant dependence of g m and g ds on both gate voltage and SB height are shown. Moreover,the scalability of f T is outstanding and close to the ideal case (f T ∝ 1/L2g ). The high frequency performances of 45 nm channel length SB-nMOSFETs at ballistic transport limit are also investigated. Results show that scattering strongly affects the capacitances C gs,C gd and C *** ballistic transport limit the f T and f max are almost 10 times *** Scattering effects in nano-scale SB-nMOSFETs cannot be neglected.

关键词： Monte Carlo ultra thin body (UTB) Schottky-barrier MOSFETs (SB-MOSFETs) high frequency

VHF-PECVD制备微晶硅材料及电池初步研究

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

太阳能学报 2004年第6期25卷 789-793页

作者：张晓丹朱锋赵颖薛俊明孙建耿新华熊绍珍南开大学光电所天津300071

研究了用甚高频等离子体增强化学气相沉积(VHF-PECVD)方法制备的不同沉积气压下的微晶硅薄膜样品。随着沉积气压的逐渐增大,样品的沉积速率也逐渐增大;样品的光敏性和激活能测试结果表明:随气压的变化两者发生了规律性一致的变化;傅立... 详细信息

研究了用甚高频等离子体增强化学气相沉积(VHF-PECVD)方法制备的不同沉积气压下的微晶硅薄膜样品。随着沉积气压的逐渐增大,样品的沉积速率也逐渐增大;样品的光敏性和激活能测试结果表明:随气压的变化两者发生了规律性一致的变化;傅立叶变换红外(FTIR)测试表明制备的样品中含有一定量的氧,使得样品呈现弱n型;室温微区喇曼光谱测试分析得到样品的微晶化特征与IR的分析是一致的,用高斯函数对喇曼谱解谱分析定量得出了晶化程度;分析了H处理p/I界面对电池性能的影响;首次在国内用VHF-PECVD制备出效率达4.24%的微晶硅电池。

关键词：甚高频等离子体增强化学气相沉积微晶硅薄膜微晶硅电池微区喇曼光谱傅立叶变换红外光谱

基于SOI技术的单层多晶EEPROM和SONOS EEPROM抗总剂量辐照特性研究

在线全文

学校读者我要写书评

暂无评论

物理学报 2011年第2期60卷 762-767页

作者：肖志强李蕾蕾张波徐静陈正才电子科技大学电子薄膜与集成器件国家重点实验室中国电子科技集团公司第五十八研究所西安电子科技大学微电子学院

在自行研发的0.8μm SOI工艺平台上开发了基于SOI技术的单层多晶硅EEPROM(electrically erasable programmable read only memory)和SONOS(silicon-oxide-nitride-oxide-silicon)EEPROM,并进行了抗总剂量辐照实验研究,分析了各种EEPROM结构在抗总剂量辐照下的失效机理.结果表明基于SOI技术的SONOS EEPROM具有良好的抗总剂量辐照性能,为抗辐照EEPROM电路中的存储单元结构选取提供了依据.

关键词： EEPROM SOISONOS 辐照浮栅

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth Sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2 & LENG Qin1,3 1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,china 2 Graduate School of Chinese Academy of Sciences,Beijing 100049,china 3 Department of Science and Technology,Bryant university,Smithfield RI 02917,USA 1. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100049 China3. Department of Science and Technology Bryant University Smithfield RI 02917 USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

Second mode unstable disturbance measurement of hypersonic boundary layer on cone by wavelet transform

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2011年第4期27卷 488-493页

作者： Jian Han.Nan Jiang.Yan Tian Department of Mathematics,Tianjin university,300072 Tianjin,china Department of Mechanics,Tianjin university,300072 Tianjin,china Tianjin Key Laboratory of Modern Engineering Mechanics,300072 Tianjin,china State Key Laboratory of Nonlinear Mechanics,institute of Mechanics,Chinese Academy of Sciences,100190 Beijing,china Department of Mathematics Tianjin University Tianjin China Department of Mechanics Tianjin University Tianjin China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

Experimental investigation of hypersonic boundary layer instability on a cone is performed at Mach number 6 in a hypersonic wind tunnel. Time series signals of instantaneous fluctuating surface-thermal-flux are measured by Pt-thin-film thermocouple temperature sensors mounted at 28 stations on the cone surface in the streamwise direction to investigate the development of the unstable disturbance. Wavelet transform is employed as a mathematical tool to obtain the multi-scale characteristics of fluctuating surfacethermal-flux both in the temporal and spectrum space. The conditional sampling algorithm using wavelet coefficient as an index is put forward to extract the unstable disturbance waveform from the fluctuating surface-thermal-flux *** generic waveform for the second mode unstable disturbance is obtained by a phase-averaging technique. The development of the unstable disturbance in the streamwise direction is assessed both in the temporal and spectrum space. Our study shows that the local unstable disturbance detection method based on wavelet transformation offers an alternative powerful tool in studying the hypersonic unstable mode of laminar-turbulent transition. It is demonstrated that, at hypersonic speeds, the dominant flow instability is the second mode, which governs the course of laminar-turbulent transition of sharp cone boundary layer.

关键词： Hypersonic boundary layer. Sharp cone Insta-bility Wavelet transform

Performances of carbon nanotube field effect transistors with altered channel length

在线全文

学校读者我要写书评

暂无评论

Science china(Technological Sciences) 2010年第1期53卷 253-256页

作者： FENG Ying,HUANG ShiHua,KANG Kai & FENG YuGuang institute of Optoelectronic Technology,Beijing Jiaotong university,Beijing 100044,china 1. institute of Optoelectronic Technology Beijing Jiaotong University Beijing 100044 China

The influence of channel length on the performances of carbon nanotube field effect transistors(CNT-FETs) has been *** oxide etching was used to remove approximately a 60 nm layer from the original 100 nm silicon dioxide layer,to thin the dielectric layer of the back *** length of the CNT-FETs was changed along with the etching *** dependence of drain-source current on gate voltage was measured to analyze the performance of the CNT-FETs,including the transconductance,carrier mobility,current ON/OFF ratio,*** results indicate that the devices still keep good quality.

关键词： carbon nanotube field effect transistors mobility buffered oxide etching

Organic thin-film solar cells:devices and materials

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2012年第4期55卷 553-578页

作者： LI ZhiGang1, ZHAO XinYan2, LI Xin1,2, GAO ZhiQiang1, MI BaoXiu1 & HUANG Wei2 1Jiangsu Engineering Centre for Flat-Panel Displays & Solid-state Lighting and School of Materials Science & Engineering, Nanjing university of Posts & Telecommunications, Nanjing 210046, china 2Key Laboratory for Organic electronics & Information Displays (KLOEID) institute of Advanced Materials (IAM), Nanjing university of Posts & Telecommunications, Nanjing 210046, china 1. Jiangsu Engineering Centre for Flat-Panel Displays & Solid-state Lighting and School of Materials Science & Engineering Nanjing University of Posts & Telecommunications Nanjing 210046 China2. Key Laboratory for Organic Electronics & Information Displays (KLOEID) institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing 210046 China

In recent years, the performance of organic thinfilm solar cells has gained rapid progress, of which the power conversion efficiencies （r/p） of 3%-5% are commonly achieved, which were difficult to obtain years ago and are improving steadily now. The r/p of 7.4% was achieved in the year 2010, and r/p of 9.2% was disclosed and confirmed at website of Mitsubishi Chemical in April, 2011. The promising future is that the r/p of 10% is achievable according to simulation results. Apparently, these are attributed to material innovations, new device structures, and also the better understanding of device physics. This article summarizes recent progress in organic thinfilm solar cells related to materials, device structures and working principles. In the device functioning part, after each brief summary of the working principle, the methods for improvements, such as absorption increment, organic/electrode interface engineering, morphological issues, are addressed and summarized accordingly. In addition, for the purpose of increasing exciton diffusion efficiency, the benefit from triplet exciton, which has been proposed in recent years, is highlighted. In the active material parts, the chemical nature of materials and its impact on device performance are discussed. Particularly, emphasis is given toward the insight for better understanding device physics as well as improvements in device performance either by development of new materials or by new device architecture.

关键词： organic – solar cell – photovoltaic – devices – materials