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摘要
碳纳米管(CNT)由于其优异的场发射特性,被作为阴极发射材料广泛应用于真空电子器件中。研究CNT薄膜的场发射行为特性,对设计和制造性能优异的CNT薄膜冷阴极器件具有重要指导作用。通过酞菁铁(FePc)热解法在铜铬复合基底上制备出有束状CNT团聚颗粒随机分布的CNT薄膜。在场发射过程中,该CNT薄膜的最大发射电流表现出增强趋势。通过对比CNT薄膜场发射前后的SEM图片以及场发射图片,分析CNT薄膜微观形貌和有效发射区域的变化。结果表明:束状团聚颗粒CNT薄膜,以单个束状CNT颗粒为发射单位,尺寸最大的CNT颗粒优先发射。由于过大场发射电流对发射单位的损坏,束状CNT颗粒根据尺寸由大到小依次成为主要发射点,由此引起有效发射点数或发射面积的改变,间接影响发射电流大小和发射区域改变。因此,可通过控制CNT薄膜束状团聚颗粒的生长分布或老化损伤处理来调控场发射电流大小,改善CNT薄膜的发射性能。
Abstract
Carbon nanotubes used as the cathode emission materials are widely used in vacuum electronic devices because of its excellent field emission properties.Research on field emission behavior characteristic of carbon nanotube film,has an important guiding role to the design and manufacture of performance of CNT film cold cathode device.CNT film with randomly distributed bundle-like agglomeration was prepared on copper chromium composite substrate by FePc pyrolysis method.In the field emission process,the largest emission current of CNT film had an increase trend.The change of CNT film micro-structure and effective emission area were analyzed by comparing the field emission images and SEM photos of CNT film before and after field emission.Studies shown that:the single bundle-like agglomeration of CNT was a unit on CNT film and the largest bundle-like agglomeration was the first field emission unit prior to other units.Because the larger field emission units were damaged by the large field emission current first,the bundle-like agglomeration from big to small according to size become the main field emission units in turn.Which caused the change of field emission points or area,and indirectly affected the emission current size and the change of field emission region.So that,the emission current size can been regulated,and the emission properties of CNT film were improved by controlling the growth of CNT film with bundle-like agglomeration or aging damage processing.
关键词
碳纳米管
/
束状团聚颗粒
/
场发射
Key words
carbon nanotube
/
bundle-like agglomeration
/
field emission
束状团聚颗粒碳纳米管薄膜场发射行为研究[J].
化工新型材料, 2018, 46(11): 111-114 DOI:
[1] Baughman R H,Zakhidov A A,Heer W A D.Carbon nanotubes-the route toward applications[J].Science,2002,297(5582):787-792.
[2] Rinzler A G,Smalley R E.Unraveling nanotubes:field emission from an atomic wire[J].Science,1995,269(5230):1550-1553.
[3] Heer W A D,Chatelain A,Ugarte D.A carbon nanotube field-emission electron source[J].Science,1995,270(5239):1179-1180.
[4] De J N,Bonard J M.Carbon nanotube electron sources and applications[J].Philosophical Transactions of the Royal Society A Mathematical Physical & Engineering Sciences,2004,362(1823):2239-2266.
[5] Teo K B K,Chhowalla M,Amaratunga G A J,et al.Fabrication and electrical characteristics of carbon nanotube-based microcathodes for use in a parallel electron-beam lithography system[J].Journal of Vacuum Science & Technology B:Microelectronics and Nanometer Structures,2003,21(2):693-697.
[6] Teo K B K,Chhowalla M,Amaratunga G A J,et al.Fabrication and electrical characteristics of carbon nanotube-based microcathodes for use in a parallel electron-beam lithography system[J].Journal of Vacuum Science & Technology B:Microelectronics and Nanometer Structures,2003,21(2):693-697.
[7] Teo K B,Minoux E,Hudanski L,et al.Microwave devices:carbon nanotubes as cold cathodes[J].Nature,2005,437(7061):968-968.
[8] Jonge N D,Lamy Y,Schoots K,et al.corrigendum:high brightness electron beam from a multi-walled carbon nanotube[J].Nature,2002,420(6914):393-5.
[9] 麻华丽,霍海波,曾凡光,等.两种微结构阵列上碳纳米管薄膜强流脉冲发射比较[J].人工晶体学报,2014(8):2098-2101.
[10] 麻华丽,霍海波,曾凡光,等.微锥阵列对碳纳米管薄膜强流脉冲发射的影响[J].人工晶体学报,2016(6):1581-1584.
[11] 周雪东,雷威,张宇宁,等.丝网印刷制备碳纳米管场发射阴极的研究[J].真空科学与技术学报,2004,24(1):47-50.
基金资助
国家自然科学基金(11404291);河南省科技创新杰出人才(164200510006);航空科学基金(2014ZF55013和2015ZF55013);河南省高校科技创新人才支持计划(17HASTIT016)
