Field emission from diamond nanotips treated with nitrogen plasma immersion ion implantation
Field emission from diamond nanotips treated with nitrogen plasma immersion ion implantation
复制标题
DOI：
10.1088/0957-4484/18/45/455706
复制
发表时间：
2007-11
期刊：
影响因子：
3.5
通讯作者：
M. Chen;K. Wu;J. Hwang;M. Chang;L. Chou;C. Kou
中科院分区：
文献类型：
--
作者：
M. Chen;K. Wu;J. Hwang;M. Chang;L. Chou;C. Kou
采用微波等离子体增强化学气相沉积法在金刚石/硅衬底上制备了金刚石纳米尖。金刚石纳米尖端的高度为101 μm，纳米尖端底部的直径为10200 nm。用氮等离子体浸没离子注入（PIII）处理10 min后，生长的金刚石纳米尖显示出优异的场发射特性。在9 V µm −1时，实现了3 V µm −1的低开启场和4 mA cm−2的高电流密度。金刚石纳米尖的形貌在氮PIII处理后没有变化。钻石质量随着处理时间的延长而降低。在-25 kV脉冲电压下，氮离子加速金刚石中的sp3键断裂，导致拉曼谱G峰展宽。用高分辨透射电子显微镜观察到，在结晶金刚石纳米尖中产生了几个纳米级的非晶区。场发射性能的改善与非晶区和可能的退火诱导的原子缺陷有关。
Diamond nanotips were synthesized on diamond/Si substrates by using a microwave plasma-enhanced chemical vapor deposition process. The diamond nanotips are ∼1 µm in height and the diameter at the bottom of a nanotip is ∼200 nm. The as-grown diamond nanotips exhibit excellent field emission characteristics after treating with nitrogen plasma immersion ion implantation (PIII) for 10 min. A low turn-on field of 3 V µm−1 and a high current density of 4 mA cm−2 at 9 V µm−1 are achieved. The morphologies of diamond nanotips are unchanged after the nitrogen PIII treatment. The diamond quality reduces with treatment time. The sp3 bonds in diamond can be broken by the nitrogen ions accelerated by the pulse voltage of −25 kV, which results in G peak broadening in Raman spectra. Several nanoscale amorphous regions are generated in a crystalline diamond nanotip, observed by the high resolution transmission electron microscope. The improvement of field emission properties is correlated to the amorphous regions and possible implantation-induced atomic defects.