基于CVD直接生长法的碳纳米管场发射阴极  

Carbon nanotube field emission cathode based on direct growth technique

作　　者：周彬彬 张建[1] 何剑锋 董长昆[1] ZHOU Bin-bin;ZHANG jian;HE Jian-feng;DONG Chang-kun(Institute of Micro-Nano Structures ＆ Optoelectronics,Wenzhou University,Wenzhou 325035,China)

机构地区：[1]温州大学微纳结构与光电器件研究所,浙江温州325035

出　　处：《真空》2018年第5期10-14,共5页Vacuum

基　　金：国家自然科学基金资助;项目号:(61620106006;11274244)

摘　　要：碳纳米管(CNT)场发射阴极具有启动快、分辨率高、寿命长、功耗小等优点,在多种真空电子设备与器件上,包括平板显示器、真空测量、微波管、X射线管等得到了应用。本文讨论了碳纳米管阴极的主要制备方法以及存在的问题,介绍了基于化学气相沉积法和阳极化工艺、在含催化金属基底直接制备碳纳米管冷阴极所具有强附着力特点,以及应用在X射线管等强流真空电子器件上的优势。文章介绍了在不锈钢基底直接生长CNT阴极的场发射性能,其开启电场为1.46 V/μm。与常规催化金属镀膜层上生长的CNT阴极相比,大电流发射与稳定性显著提高。金属基底阳极化工艺显著改善碳纳米管结构与场发射性能。直径2 cm的不锈钢基底上生长的CNT具有晶体性好、分布均匀等特点,场发射性能提高。在镍基底上生长的CNT阴极电流密度可以达到500 mA/cm^2以上。Carbon nanotube（CNT） field emission cathode has the advantages of quick start, high resolution, long lifetime, and low power consumption. The CNT cathode can be employed in a variety of vacuum electronic devices and components,including flat panel display, vacuum measurement, and vacuum electronic devices. This article discusses major methods for development of carbon nanotube cathode, and emphasizes on direct growth of CNT emitters on catalytic substrate by chemical vapor deposition and substrate anodization with strong adhesion and advantages for applications in the X-ray tube and other vacuum electronic devices. The field emission properties of CNT cathode grown directly on stainless steel substrate are investigated, with the turn-on electric field of 1.46 V/μm. The high current emission and stability properties of the direct grown CNT emitters are improved significantly comparing with that of the CNT cathode by conventional synthesis on catalytic metal film. The substrate anodization improves clearly the CNT structure and field emission performance. Advantages of large scale production of up to 2 cm in diameter and high current emission of 500 mA/cm^2 are also demonstrated.

关 键 词：碳纳米管 场发射 直接生长法 阳极化 化学气相沉积 

分 类 号：TN304[电子电信—物理电子学] TH813[机械工程—仪器科学与技术]