ECR微波等离子体对单晶金刚石表面的碳纳米墙修饰

利用电子回旋共振(ECR)微波等离子体，在CH₄/H₂体系下，对高温高压单晶金刚石表面进行了碳纳米墙修饰。通过等离子体发射光谱研究ECR等离子体内基团的谱线强度在不同工作气压、CH₄浓度下的变化规律，结合扫描电子显微镜对单晶金刚石表面的微观形貌进行分析，进一步研究了工作气压和CH₄浓度对碳纳米墙修饰结果的影响。结果表明:碳纳米墙的取向性受工作气压影响大，低气压(0.07 Pa)条件下生长的碳纳米墙垂直取向明显，金刚石表面也出现垂直刻蚀形貌；在高气压(5 Pa)条件下生长的碳纳米墙取向性较差。同时，碳纳米墙生长的临界CH₄浓度也与工作气压有关:低气压条件下碳纳米墙生长的临界CH₄浓度高，工作气压为0.07 Pa时，碳纳米墙生长的临界CH₄浓度为3%；工作气压升至5 Pa时，碳纳米墙生长的临界CH₄浓度降为1%，碳纳米墙密度随CH₄浓度升高而增大。 

Carbon nanowalls modifying single crystal diamond surface by ECR microwave plasma

Carbon nanowalls were modified on the surface of high temperature and high pressure single crystal diamond by electron cyclotron resonance(ECR)microwave plasma under CH 4/H 2 system in this paper.The plasma emission spectroscopy was used to study the variation of the spectral intensity of the CH 4/H 2 ECR plasma in different working pressures and CH 4 concentrations.The micro structure of the single crystal diamond was analyzed by scanning electron microscopy(SEM)and the effects of pressure and CH 4 concentration on the modification results of carbon nanowalls were further studied.The results show that the orientation of carbon nanowalls is greatly affected by the working pressure.The carbon nanowalls grown under low pressure(0.07 Pa)have vertical orientation,and the surface of the diamond also has vertical etched morphology.At high pressure(5 Pa),the underlying carbon nanowalls have poor orientation.At the same time,the critical CH 4 concentration of carbon nanowalls growth is also related to the working pressure.The critical CH 4 concentration of carbon nanowalls growing under low pressure is higher.When the working pressure is 0.07 Pa,the critical CH 4 concentration of carbon nanowalls growth is 3%.When the working pressure is increased to 5 Pa,the critical CH 4 concentration of carbon nanowalls growth is reduced to 1%.And the density of carbon nanowalls increases proportionally with CH 4 concentration.