共查询到18条相似文献,搜索用时 156 毫秒
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《真空电子技术》1971,(2)
阴极中毒是因发射表面上吸附气体层之故。吸附气体的量与吸附热、气体压强以及阴极温度有关。吸附的气体在阴极表面上形成带电偶极子,它导致逸出功增加,从而引起发射下降或阴极中毒。因为偶极矩大小和吸附气体的量非定量所知,所以通过实驗測量阴极中毒。本文叙述使用的实驗裝置和实驗方法。介紹的实驗結果包括鎢阴极、六硼化鑭阴极和浸漬镧的碳化鎢阴极受氧的中毒。六硼化鑭阴极的抗氧中毒的能力强于鎢或浸漬鑭的磺化鎢阴极。还测量了六硼化鑭阴极受氮、二氧化碳、空气、氬和氫等气体的中毒特性。测得的鎢阴极、六硼化鑭阴极和浸漬鑭的磺化鎢阴极受氧中毒的特性,与其他不同类型阴极受氧中毒的数据作了比較。这就为选择使用在中毒环境下的阴极提供定量基础。 相似文献
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采用电子束蒸发方法在商用PDP玻璃衬底和Ta衬底上沉积六硼化镧薄膜。分别对PDP玻璃衬底上沉积的六硼化镧薄膜的可见光范围内的透过率、薄膜生长取向和附着力进行了研究;对钽衬底上沉积的六硼化镧薄膜阴极的逸出功进行了研究。结果表明,制备的六硼化镧薄膜厚度为43nm时,在可见光范围内透过率大于90%,优于传统MgO保护层;六硼化镧薄膜具有(100)晶面择优生长的特点,薄膜的晶格常数与靶材相差小于0.2‰,薄膜的晶粒细小,成膜致密均匀;制备的透明六硼化镧薄膜的逸出功为2.56eV。 相似文献
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为了研究镧钼阴极表面发射机制,采用专为研究阴极设计的与俄歇能谱仪相连的脉冲激光沉积装置制备薄膜阴极.通过测量阴极发射性能和原位分析表面成分(原子数分数),研究了阴极表面元素镧La和氧O变化对阴极发射性能的影响.实验发现随着阴极表面镧膜变薄,阴极发射性能逐渐减弱;阴极发射性能与表面元素La,O 的含量有关,表面层中La/O越高,阴极的发射性能越好.结果表明,传统的单原子层理论无法解释镧钼阴极的发射机制;超额镧在镧钼阴极的发射中起到了关键作用. 相似文献
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William M. Jones Runyu Zhang Eshwari Murty Xiuting Zhu Yifan Yao Harish Manohara Paul V. Braun Lauren C. Montemayor 《Advanced functional materials》2019,29(16)
Electronics to be used in space must often perform in high temperature or radiation hard environments that render conventional solid‐state technologies unable to meet mission requirements. As a result, microscale and nanoscale field emission devices are being explored as fundamental components of electronics capable of operating in these harsh environments. Wide scale implementation of these devices is hindered by the difficulty of fabricating large, mechanically stable, uniform arrays of sharp emitting tips. This work presents a scalable method to produce uniform arrays of field emitting tips. Polystyrene spheres are applied as a template for electrochemical deposition. An electrochemical etching process is developed to sharpen tips to a radius of curvature of 5–10 nm, optimizing them for field emission applications. The flexibility of the fabrication process allows for device optimization in terms of tip geometry, density, and constituent material to achieve high field enhancement factors, exceeding 100. Miniaturized field emitting diode and gated triode devices are fabricated. Finally, the electrochemically deposited material is used as a scaffold for the deposition of a refractory, low work function emitting layer, and the hybrid cathode is characterized as a field emitter at temperatures up to 300 ºC. 相似文献
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为了进一步降低PDP面板着火电压,提高其放电效率,采用丝网印刷方法在商用PDP玻璃衬底上印刷LaB6薄膜.分别对PDP玻璃衬底上印刷的LaB6薄膜的可见光范围内的透过率、薄膜表面形貌进行了研究;对印刷了LaB6薄膜的PDP玻璃衬底进行了封装,测试了其在Xe-Ne环境下的放电特性.结果表明,印刷了LaB6作为添加层的放电单元相比传统单一MgO保护层的放电单元,其着火电压和放电延迟分别降低了5%和25%.说明采用高二次电子发射系数的六硼化镧材料能够有效提升PDP的放电性能. 相似文献
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E. Gat F. Bounasri M. Chaker M. F. Ravet M. Moisan J. Margot 《Microelectronic Engineering》1996,30(1-4):337-340
The influence of the substrate temperature (from Ts = +20°C to Ts = −45°C) on the etching characteristics (etch rate and anisotropy) of tungsten material has been investigated using a surface-wave sustained magnetoplasma reactor operated with SF6. By correlating the F-atom concentration and the ion current density to the etching characteristics, we found that ion-assisted etching becomes more important than spontaneous chemical etching as the substrate temperature and SF6 gas pressure decrease, ensuring, in absence of external biasing, high etching anisotropy together with high microscopic uniformity for submicrometer features (0.2 to 1 μm). Our results reveal the competitive influence between substrate temperature (which inhibits spontaneous chemical reaction as it is lowered) and gas pressure (which favours spontaneous chemical reaction as it is increased). Obtaining high anisotropy requires, in the present case, a substrate temperature of Ts = −20°C for P = 0.5 mTorr and a temperature as low as Ts = −35°C for P = 1.5 mTorr. 相似文献
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添加剂在扩散式阴极基底中的作用 总被引:1,自引:0,他引:1
文章着重介绍掺入扩散式有基底中添加剂Cr2O3,InO,In2O3,ZrO2,TiO2,TiO2+H2IrO6,不仅降低了阴极的逸出功,增大了发射电流密度降低了工作温度,延长了寿命,减少了发射物质蒸发,还增强了耐离子轰击特性。 相似文献