采用电子辅助化学气相沉积法(EA-CVD),在含氮气氛中制备出金刚石膜,利用SEM、Raman光谱、EPR测试手段研究了氮气对金刚石膜品质的影响及氮掺杂特性.结果表明,在950℃基片温度下,沉积气氛中掺入氮气后,金刚石膜晶形变为“菜花状”,非金刚石碳的含量增加,膜的品质下降.在800℃基片温度下,沉积气氛中掺入氮气后,孪晶和二次成核减少,金刚石膜的结晶形貌得到改善.通过Raman光谱和EPR分析发现,在金刚石膜中氮杂质主要以Ns0,[N-V]0和[N-V]-1的形式存在,而且随着氮气流量的增加,Ns0的含量增加,[N-V]0含量减少,[N-V]-1含量变化不明显.
Diamond films were prepared by an electron assisted chemical vapor deposition system (EA-CVD) in an atmosphere with a nitrogen addition. SEM,Raman spectroscopy,and EPR were employed to study the influence of nitrogen on the films' quality and the characteristics of nitrogen doping. The results show that for the films deposited at 950℃, the morphology changes to cauliflower- like structures,the content of non-diamond carbon increases,and the quality drops after adding nitrogen into the atmosphere. For the films deposited at 800℃ ,the addition of nitrogen reduces the twins and secondary nucleation, and improves the films’ morphology. EPR and Raman spectra indicate that nitrogen impurities in the films mainly exist in the forms of Ns^0 ,[N-V]^0 ,and [N-V]^-1. Along with the increase of nitrogen flow rate, the content of Ns^0 increases, the content of [N-V]^0 decreases, and the content of [N-V]^-1 does not change obviously.