电磁场辅助HFCVD制备高场发射性能薄膜

发布时间：2018-01-29 07:39

本文关键词： 化学气相沉积电磁耦合场金刚石石墨纳米尖锥场致电子发射　出处：《表面技术》2017年08期 　论文类型：期刊论文

【摘要】：目的提高碳素薄膜的场发射性能。方法在热丝化学气相沉积(HFCVD)技术的基础上,针对不同的甲烷浓度(体积分数,全文同)1%和5%,通过施加外场(电场、磁场以及电磁耦合场)分别调控出不同组织结构的薄膜。采用SEM观察薄膜的表面形貌,用Raman检测薄膜的成分,用场发射测试装置来表征薄膜的场发射性能。结果外场作为革新传统工艺的手段,可以影响HFCVD沉积过程。磁场的主要作用是降低晶粒尺寸,电场能够有效促进sp~3相向sp~2相转变,电磁耦合场在此基础上,还可以有效调控出高长径比的表面形貌。甲烷浓度为1%时,制备了金刚石薄膜,开启电场为11.2 V/μm,加入电场或电磁耦合场后,薄膜表面被刻蚀,发生金刚石向石墨的转变,开启电场降低到6.75 V/μm,场发射性能提高。甲烷浓度为5%时,加入磁场、电场制备的薄膜,开启电场由12.75 V/μm依次下降为11.5、9 V/μm,电磁耦合场的刻蚀作用可以获得尖锥状的形貌,且石墨相含量高,开启电场最低(5.65 V/μm),场发射性能最好。结论采用外场(电场、磁场以及电磁耦合场)辅助HFCVD的方式可以制备出多种薄膜,电磁耦合场在较高甲烷浓度时,不但可以提高石墨相含量,还可以获得高长径比的表面形貌,可有效提高薄膜的场发射性能。
[Abstract]:Objective to improve the field emission properties of carbon thin films. Methods based on the hot filament chemical vapor deposition (HFCVD) technique, different concentrations of methane (volume fraction, 1% and 5%) were studied. The films with different structure were regulated by external field (electric field, magnetic field and electromagnetic coupling field). The surface morphology of the film was observed by SEM and the composition of the film was detected by Raman. The field emission test device was used to characterize the field emission properties of the films. Results as a means of innovating the traditional process, the external field can affect the deposition process of HFCVD. The main function of magnetic field is to reduce the grain size. The electric field can effectively promote the phase transition from sp~3 to sp~2. On the basis of the electromagnetic coupling field, the surface morphology of the ratio of height to diameter can be effectively controlled. Diamond thin films are prepared when the methane concentration is 1. The opening electric field is 11.2 V / 渭 m. When the electric field or electromagnetic coupling field is added, the surface of the film is etched, and the transition of diamond to graphite occurs, and the open electric field decreases to 6.75 V / 渭 m. The field emission performance is improved. When methane concentration is 5, the film prepared by adding magnetic field and electric field decreases from 12.75 V / 渭 m to 11.59 V / 渭 m in turn. The electromagnetically coupled field etching can obtain sharp conical morphology, high graphite phase content, the lowest open electric field (5.65 V / 渭 m), and the best field emission performance. Conclusion the external field (electric field) is used. Many kinds of films can be prepared by magnetic field and electromagnetic coupling field (HFCVD). When the concentration of methane is high, the content of graphite phase can be increased. The surface morphology of the films with high aspect ratio can also be obtained, and the field emission properties of the films can be improved effectively.
【作者单位】：中南大学材料科学与工程学院;中南大学粉末冶金研究所;
【基金】：国家自然科学基金资助项目(51301211,21271188)~~
【分类号】：TB383.2;TQ127.11
【正文快照】： Received:2017-02-12;Revised:2017-03-12innovating traditional crafts,external field could influence the deposition process of CVD.The magnetic field could reducegrain size while electric field could effectively promotetranformation from sp3 phase to sp2 p

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