期刊文献+
共找到18篇文章
< 1 >
每页显示 20 50 100
微波管栅发射问题的研究 被引量:3
1
作者 王小霞 廖显恒 +2 位作者 赵青兰 余晓军 张济忠 《电子与信息学报》 EI CSCD 北大核心 2002年第7期1005-1008,共4页
利用离子束辅助沉积技术在 Mo栅极上镀上并注入一层 Hf膜,对镀后的样品进行了形貌、结构、成份、膜厚及 Mo、Hf界面分析。将样品进行电子管模拟栅发射试验,栅极温度为 650℃,试验 1000h以上基本无栅发射电流,可以提高栅控管的可靠性和... 利用离子束辅助沉积技术在 Mo栅极上镀上并注入一层 Hf膜,对镀后的样品进行了形貌、结构、成份、膜厚及 Mo、Hf界面分析。将样品进行电子管模拟栅发射试验,栅极温度为 650℃,试验 1000h以上基本无栅发射电流,可以提高栅控管的可靠性和寿命。实验结果表明,阴极中的活性物质Ba蒸发到镀Hf的 Mo栅极表面,Ba,Hf和O_2能形成化合物,从而有效抑制栅极发射电流。 展开更多
关键词 微波管 栅发射 离子束辅助沉积 化合物
下载PDF
Hf栅极栅电子发射的研究 被引量:1
2
作者 赵青兰 王小霞 +2 位作者 廖显恒 王其富 李云 《真空科学与技术学报》 EI CAS CSCD 北大核心 2011年第5期603-606,共4页
栅发射在栅控行波管及速调管中是较为普遍的现象,为了降低栅发射,通常采用高功函数金属作为栅极或在栅极表面沉积高功函数物质或沉积能与蒸散到栅极上的活性物质反应形成高功函数化合物的金属。本文直接采用纯金属Hf作为栅极,与普通Mo... 栅发射在栅控行波管及速调管中是较为普遍的现象,为了降低栅发射,通常采用高功函数金属作为栅极或在栅极表面沉积高功函数物质或沉积能与蒸散到栅极上的活性物质反应形成高功函数化合物的金属。本文直接采用纯金属Hf作为栅极,与普通Mo栅极对比,研究了Hf栅极在模拟电子管中管子激活前、阴极激活后栅发射的情况,并对氧化物阴极加速寿命中栅发射情况进行测试分析。结果表明:在阴极激活前后及寿命过程中,纯Hf栅极具有较小的栅发射电流。 展开更多
关键词 Hf 栅发射电流 浸渍Ba-W阴极 氧化物阴极
下载PDF
C、Hf薄膜抑制栅极电子发射的机理研究
3
作者 吴雪梅 诸葛兰剑 柳襄怀 《功能材料》 CSCD 北大核心 2005年第z1期28-30,35,共4页
利用双离子束溅射和射频磁控溅射技术在Mo基底上分别制备了C膜和Hf膜,并利用化学方法制备了BaO涂层以模拟行波管栅极结构,随后在N2保护下,通过在900~1300K 范围内退火,研究样品处于高温工作环境下表面相结构和成分的变化,以此解释了C... 利用双离子束溅射和射频磁控溅射技术在Mo基底上分别制备了C膜和Hf膜,并利用化学方法制备了BaO涂层以模拟行波管栅极结构,随后在N2保护下,通过在900~1300K 范围内退火,研究样品处于高温工作环境下表面相结构和成分的变化,以此解释了C、Hf薄膜抑制栅极电子发射的工作机理。 展开更多
关键词 栅发射 C薄膜 Hf薄膜 BAO
下载PDF
SiO_2/聚酰亚胺/SiO_2复合薄膜绝缘性能及基于聚酰亚胺复合薄膜的后栅型场致发射性能的研究 被引量:2
4
作者 郑灼勇 于光龙 +3 位作者 张志坚 陈景水 郭太良 张永爱 《真空科学与技术学报》 EI CAS CSCD 北大核心 2012年第3期214-218,共5页
使用射频磁控溅射和化学溶液法制备了SiO2/聚酰亚胺(PI)/SiO2绝缘膜。分别使用X射线衍射、扫描电镜对薄膜结构和薄膜表面形貌进行了表征;利用超高阻微电流测试仪测试了SiO2/PI/SiO2复合绝缘膜漏电流和电压击穿特性;采用SiO2/PI/SiO2作... 使用射频磁控溅射和化学溶液法制备了SiO2/聚酰亚胺(PI)/SiO2绝缘膜。分别使用X射线衍射、扫描电镜对薄膜结构和薄膜表面形貌进行了表征;利用超高阻微电流测试仪测试了SiO2/PI/SiO2复合绝缘膜漏电流和电压击穿特性;采用SiO2/PI/SiO2作为绝缘膜,制作了后栅型场致发射器件,使用场发射测试系统测试了器件的开启电压、发射电流以及发光亮度。结果表明:SiO2/PI/SiO2复合绝缘膜具有高的击穿电压和低的漏电流密度,后栅器件中栅极对阴极表面的电场强度调控作用明显,阳极电压为750V时,栅极开启电压为91 V,阳极电流可达384μA,栅极漏电流仅为59μA,器件最高亮度可达600 cd/m2。 展开更多
关键词 聚酰亚胺场发射复合薄膜后
下载PDF
金属钼、铪栅极材料电子发射问题研究
5
作者 方有维 刘林 +1 位作者 俞世吉 李玉涛 《真空》 CAS 2022年第6期60-64,共5页
利用离子束辅助沉积技术在Ba-W阴极表面上分别沉积金属钼膜和铪膜,以模拟栅控行波管中钼栅极和铪栅极表面吸附阴极蒸发物质时的表面状态。研究了这两种栅极表面微观结构和成分的变化,并测试了其表面热电子发射能力和二次电子发射系数。... 利用离子束辅助沉积技术在Ba-W阴极表面上分别沉积金属钼膜和铪膜,以模拟栅控行波管中钼栅极和铪栅极表面吸附阴极蒸发物质时的表面状态。研究了这两种栅极表面微观结构和成分的变化,并测试了其表面热电子发射能力和二次电子发射系数。实验结果表明,铪栅极表面吸附的阴极发射物质要远少于钼栅极,用金属铪作栅极材料能有效抑制栅极电子发射。 展开更多
关键词 Ba-W阴极 栅发射 热电子发射 二次电子发射系数
下载PDF
新型前栅场发射器件的研究 被引量:2
6
作者 杨帆 胡利勤 +2 位作者 林贺 郑隆武 郭太良 《真空科学与技术学报》 EI CAS CSCD 北大核心 2012年第3期192-195,共4页
采用刻蚀型介质制作前栅场发射器件。该器件中阴栅结构的形成是利用刻蚀工艺刻蚀介质层,一次性实现栅孔和阴极电极的连通,最后利用电泳沉积工艺转移碳纳米管制备成阴极发射点阵。该工艺避免了对准或套印,使前栅场发射器件制作工艺更简单... 采用刻蚀型介质制作前栅场发射器件。该器件中阴栅结构的形成是利用刻蚀工艺刻蚀介质层,一次性实现栅孔和阴极电极的连通,最后利用电泳沉积工艺转移碳纳米管制备成阴极发射点阵。该工艺避免了对准或套印,使前栅场发射器件制作工艺更简单,降低了成本,更容易实现大面积制作。场发射测试表明当阳压在1500和2000 V时,栅压都能够有效地控制阴极的电子发射。 展开更多
关键词 刻蚀型介质前发射
下载PDF
折叠波导行波管铪栅极退火温度及其性能(英文) 被引量:2
7
作者 马天军 陈振海 +3 位作者 俞世吉 孙建海 伊福廷 刘濮鲲 《材料热处理学报》 EI CAS CSCD 北大核心 2015年第S1期213-217,共5页
在充分考虑电子枪栅极的工作环境后,对铪(Hf)栅极进行了800、900和1000℃的真空退火处理,对其组织、织构特点进行了分析,并利用离子束辅助沉积技术在Ba-W阴极表面分别沉积金属钼膜和铪膜,以模拟栅控行波管中钼栅极和铪栅极表面吸附阴极... 在充分考虑电子枪栅极的工作环境后,对铪(Hf)栅极进行了800、900和1000℃的真空退火处理,对其组织、织构特点进行了分析,并利用离子束辅助沉积技术在Ba-W阴极表面分别沉积金属钼膜和铪膜,以模拟栅控行波管中钼栅极和铪栅极表面吸附阴极蒸发物质时的表面状态,测试了这两种栅极表面"热电子发射"能力和"二次电子发射"系数。结果表明,随着退火温度的升高,铪(Hf)栅极的结晶度、晶粒尺寸增加,织构减少,铪的最佳退火温度为900℃,铪栅极表面吸附的阴极发射物质要远少于钼栅极,用金属铪作栅极材料能有效抑制栅电子发射。 展开更多
关键词 退火 织构 栅发射 二次电子发射
下载PDF
离子束辅助沉积铂碳混合膜及其抑制栅电子发射性能 被引量:1
8
作者 江炳尧 冯涛 +1 位作者 王曦 柳襄怀 《功能材料与器件学报》 CAS CSCD 北大核心 2008年第4期757-762,共6页
采用离子束辅助沉积技术,在硅、钼衬底上分别制备铂碳混合膜。XRD的分析结果表明,当铂碳混合膜中铂的组份较多时,有较强的铂(111)面衍射峰和较弱的铂(200)面衍射峰,铂的组份呈(111)择优取向。Raman谱的分析结果表明,碳基本上呈非晶状态... 采用离子束辅助沉积技术,在硅、钼衬底上分别制备铂碳混合膜。XRD的分析结果表明,当铂碳混合膜中铂的组份较多时,有较强的铂(111)面衍射峰和较弱的铂(200)面衍射峰,铂的组份呈(111)择优取向。Raman谱的分析结果表明,碳基本上呈非晶状态。模拟二极管的实验表明,在纯钼阳极上镀覆铂碳混合膜,其抑制热电子发射的性能明显优于纯钼阳极。 展开更多
关键词 离子束辅助沉积 铂碳混合膜 电子发射
原文传递
固态微波毫米波、太赫兹器件与电路的新进展 被引量:11
9
作者 赵正平 《半导体技术》 CAS CSCD 北大核心 2011年第12期897-904,共8页
固态微波毫米波、太赫兹器件与电路是微电子、纳电子领域的战略制高点之一,SiCMOS技术进入纳米加工时代,GaAs,InP材料的"能带工程"(超晶格、异质结),GaN材料的宽禁带和界面特性以及石墨烯纳米级新材料的创新发展都深刻影响着... 固态微波毫米波、太赫兹器件与电路是微电子、纳电子领域的战略制高点之一,SiCMOS技术进入纳米加工时代,GaAs,InP材料的"能带工程"(超晶格、异质结),GaN材料的宽禁带和界面特性以及石墨烯纳米级新材料的创新发展都深刻影响着固态微波毫米波、太赫兹器件与电路的进展。描述了固态微波、毫米波和太赫兹器件与电路当前发展的新亮点,包括纳米加工技术、石墨烯新材料、GaN MMIC功率合成突破3 mm频段百瓦级、三端器件进入太赫兹和两端器件倍频链突破2.7 THz微瓦功率。并重点就当前发展的RF CMOS,SiGe HBT,LDMOS,GaAsPHEMT,GaAs MHEMT,InP HEMT,InP HBT,GaN HEMT,GFET和THz倍频链等10个领域的发展特点、2011年最新发展以及未来发展趋势进行介绍。 展开更多
关键词 固态微波 毫米波 太赫兹 RF CMOS 高电子迁移率晶体管 控式场发射 极管
下载PDF
New type gate electrode of CNT-FED fabricated by chemical corrosive method
10
作者 陈静 雷威 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期241-243,共3页
To obtain a triode structure canbon nanotube field emission display (CNT-FED), the glass plate which contains a glass channels matrix is designed and used as the triode part of the CNT-FED. Normally, the gate electr... To obtain a triode structure canbon nanotube field emission display (CNT-FED), the glass plate which contains a glass channels matrix is designed and used as the triode part of the CNT-FED. Normally, the gate electrode can be fabricated with screen printing methods and a channels matrix can be fabricated by two- faced chemical corrosion. By adjusting the etch time and the concentration of acid in the process, different shapes of the tunnels can be obtained. The size and morphology of channels are observed by a scanning electron microscope (SEM), and the ingredients of the corrosion solution are detected by infrared ray (IR) analysis. Voltage is added to the triode structure for obtaining the brightness image of the spot on the screen. Eventually, the electron trace pulling from cathode to anode under an electric field is obtained by simulation. It is concluded that the simulation results accord with the experimental results which realize the optimized triode structure. 展开更多
关键词 canbon nanotube field emission display (CNT-FED) gate electrode chemical corrosion glass hole
下载PDF
A Low-Power,Single-Poly,Non-Volatile Memory for Passive RFID Tags 被引量:1
11
作者 赵涤燹 闫娜 +3 位作者 徐雯 杨立吾 王俊宇 闵昊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第1期99-104,共6页
Single-poly,576bit non-volatile memory is designed and implemented in an SMIC 0.18μm standard CMOS process for the purpose of reducing the cost and power of passive RFID tag chips. The memory bit cell is designed wit... Single-poly,576bit non-volatile memory is designed and implemented in an SMIC 0.18μm standard CMOS process for the purpose of reducing the cost and power of passive RFID tag chips. The memory bit cell is designed with conventional single-poly pMOS transistors, based on the bi-directional Fowler-Nordheim tunneling effect, and the typical program/erase time is 10ms for every 16bits. A new ,single-ended sense amplifier is proposed to reduce the power dissipation in the current sensing scheme. The average current consumption of the whole memory chip is 0.8μA for the power supply voltage of 1.2V at a reading rate of 640kHz. 展开更多
关键词 RFID single-poly non-volatile memory standard CMOS process sense amplifier low power
下载PDF
Automatic Assessment of Fabric Smoothness Grade Using Double CCD Grating Projection
12
作者 陈慧敏 张渭源 顾洪波 《Journal of Donghua University(English Edition)》 EI CAS 2007年第5期614-618,共5页
Automatically assessing fabric smoothness grade is very important in the evaluation of fabric appearance.A system for objectively evaluating the fabric smoothness grade based on a grating projection unit and double co... Automatically assessing fabric smoothness grade is very important in the evaluation of fabric appearance.A system for objectively evaluating the fabric smoothness grade based on a grating projection unit and double colored CCD(short form of charge coupled device) was constructed in this paper.Two images captured by different CCD compensated each other which reduced the influence of noises.The application of the four-step phase-shifting method enabled the calculation of the exact phase in a point easy and quick.A large amount of 3D points with three coordinates X,Y and Z were obtained precisely making the definition and calculation of fabric smoothness characters easy.Then four parameters which intuitively denoted the fabric smoothness degree were obtained.Finally,a proper neural network was built,which successfully performed the fabric smoothness classification.The experimental results show that the system is applicable for all the fabric whatever pattern or color.The experimental grades provided by this grating projection system are also highly consistent with the subjective results. 展开更多
关键词 smoothness grade FABRIC grating projection double CCD
下载PDF
Optical diffraction gratings embedded in BK-7 glass by low-density plasma formation using femtosecond laser
13
作者 Jung-Kyu PARK Sung-Hak CHO +1 位作者 Kwang-Ho KIM Myung-Chang KANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第A01期165-169,共5页
The optical embedded diffraction gratings with the internal refractive index modification in BK-7 glass plates were demonstrated using low-density plasma formation excited by a high-intensity femtosecond (130 fs) Ti... The optical embedded diffraction gratings with the internal refractive index modification in BK-7 glass plates were demonstrated using low-density plasma formation excited by a high-intensity femtosecond (130 fs) Ti: sapphire laser (λp=790 rim). The refractive index modifications with diameters ranging from 400 nm to 4 gm were photoinduced after plasma formation occurred upon irradiation with peak intensities of more than 1 ×10^13 W/cm2. The graded refractive index profile was fabricated to be a symmetric around the center of the point at which low-density plasma occurred. The maximum refractive index change (An) was estimated to be 1.5x10 2. Several optical embedded gratings in BK-7 glass plate were demonstrated with refractive index modification induced by the scanning of low-density plasma formation. 展开更多
关键词 BK-7 glass plate diffraction grating refractive index modification plasma formation femtosecond laser
下载PDF
The Optical Emission Spectroscopy Experiment of Open Air Plasmas
14
作者 S. Mijovic M. Vuceljic M. Scepanovic 《Journal of Chemistry and Chemical Engineering》 2013年第7期671-673,共3页
A plasma spectroscopy experiment is described and its performances are given, ways oI excltauon u^ttc~,t tc~,,,,,~ ,,, free-burning plasma at atmospheric pressure is analyzed in detail. The fixed-grating spectrograph ... A plasma spectroscopy experiment is described and its performances are given, ways oI excltauon u^ttc~,t tc~,,,,,~ ,,, free-burning plasma at atmospheric pressure is analyzed in detail. The fixed-grating spectrograph PGS-2 Carl Zeiss Jena is actually a variation on the very first spectrometer design, where photo-plate was replaced with a detector array of PIXIS-Roper Scientific camera. Abilities of the system are analyzed and its limitations are determined. 展开更多
关键词 Plasma physic SPECTROSCOPY open air plasma.
下载PDF
FBG-based ultrasonic wave detection and acoustic emission linear location system 被引量:12
15
作者 姜明顺 隋青美 +2 位作者 贾磊 彭蓬 曹玉强 《Optoelectronics Letters》 EI 2012年第3期220-223,共4页
The ultrasonic (US) wave detection and an acoustic emission (AE) linear location system are proposed, which employ fiber Bragg gratings (FBGs) as US wave sensors. In the theoretical analysis, the FBG sensor response t... The ultrasonic (US) wave detection and an acoustic emission (AE) linear location system are proposed, which employ fiber Bragg gratings (FBGs) as US wave sensors. In the theoretical analysis, the FBG sensor response to longitudinal US wave is investigated. The result indicates that the FBG wavelength can be modulated as static case when the grating length is much shorter than US wavelength. The experimental results of standard sinusoidal and spindle wave test agree well with the generated signal. Further research using two FBGs for realizing linear location is also achieved. The maximum linear location error is obtained as less than 5 mm. FBG-based US wave sensor and AE linear location provide useful tools for specific requirements. 展开更多
关键词 Acoustic emissions SENSORS Signal detection
原文传递
Investigation on emissive properties of peroskite-type oxide LSMO with grating surface
16
作者 HUANG JinGuo XUAN YiMin LI Qiang 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第1期220-225,共6页
This paper aims to investigate thermal radiative characteristics of thermochrornic material La0.825Sr0.175MnO3(LSMO) with one-dimensional grating structured surfaces. The dielectric function of LSMO was calculated b... This paper aims to investigate thermal radiative characteristics of thermochrornic material La0.825Sr0.175MnO3(LSMO) with one-dimensional grating structured surfaces. The dielectric function of LSMO was calculated by K-K approach. Numerical calculation was conducted to obtain spectral emittance distribution of such surfaces with different structural parameters using the finite difference time domain (FDTD) method. It was found that the spectral emittance of LSMO structured surface exhib- ited the feature of selective enhancement due to the excitation of microcavity effect. The effects of structural parameters on spectral emittance indicated that the desired radiative enhancement could be achieved by the rational design of the structural parameters of grating. The temperature dependence of averaged emittance of LSMO was also calculated, The results showed that LSMO with grating structured surface had a better thermochromic performance compared with LSMO with smooth surface. 展开更多
关键词 GRATING thermochromic materials EMISSION
原文传递
Acoustic Emission Source Linear Localization Based on an Ultra-Short FBGs Sensing System 被引量:1
17
作者 Zhongwei JIN Mingshun JIANG Qingmei SUI Faye ZHANG Lei JIA 《Photonic Sensors》 SCIE EI CAS 2014年第2期152-155,共4页
An acoustic emission (AE) linear location system was proposed, which employed fiber Bragg gratings (FBGs) as AE sensors. It was demonstrated that the FBG wavelength could be modulated as the static case when the g... An acoustic emission (AE) linear location system was proposed, which employed fiber Bragg gratings (FBGs) as AE sensors. It was demonstrated that the FBG wavelength could be modulated as the static case when the grating length was much shorter than the AE wavelength. In addition, an improved AE location method based on the Gabor wavelet transform (WT) and threshold analysis was represented. The method was testified through AE linear location experiments based on a tunable narrow-band laser interrogation system using ultra-short FBG sensors as AE sensors. Results of the experiments showed that 86% of the linear location errors were less than 10mm. 展开更多
关键词 Acoustic emission (AE) linear location fiber Bragg gratings (FBGs) Gabor wavelet transform (WT) threshold analysis
原文传递
An FBG acoustic emission source locating system based on PHAT and GA
18
作者 申景诗 曾晓东 +1 位作者 李伟 姜明顺 《Optoelectronics Letters》 EI 2017年第5期330-334,共5页
Using the acoustic emission locating technology to monitor the health of the structure is important for ensuring the continuous and healthy operation of the complex engineering structures and large mechanical equipmen... Using the acoustic emission locating technology to monitor the health of the structure is important for ensuring the continuous and healthy operation of the complex engineering structures and large mechanical equipment. In this paper, four fiber Bragg grating(FBG) sensors are used to establish the sensor array to locate the acoustic emission source. Firstly, the nonlinear locating equations are established based on the principle of acoustic emission, and the solution of these equations is transformed into an optimization problem. Secondly, time difference extraction algorithm based on the phase transform(PHAT) weighted generalized cross correlation provides the necessary conditions for the accurate localization. Finally, the genetic algorithm(GA) is used to solve the optimization model. In this paper, twenty points are tested in the marble plate surface, and the results show that the absolute locating error is within the range of 10 mm, which proves the accuracy of this locating method. 展开更多
关键词 Acoustic emissions Genetic algorithms LOCATION Nonlinear equations OPTIMIZATION
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部