氘在碳钨共沉积层中的滞留行为研究

摘要

运用射频磁控溅射方法，在氘氩混合气氛中制备了含氘碳钨共沉积薄膜.利用离子束分析方法[卢瑟福背散射(RBS)和弹性反冲(ERD)]对薄膜样品的厚度、成分、氘含量等进行了分析；利用拉曼光谱和扫描电子显微镜(SEM)，分别分析了薄膜的结构和表面形态.离子束分析发现，氘原子更易被碳原子俘获位俘获，并且氘含量会随着沉积温度的升高而降低；其他镀膜条件固定的情况下，不同混合气体压强下薄膜样品中的氘浓度在5.0 Pa处有一个峰值；拉曼光谱分析显示，沉积温度从室温升高到725 K时，碳钨共沉积层中的类石墨化成分增加，同时，非晶化的程度也加剧；扫描电子显微镜图像表明，随着温度的升高薄膜表面被腐蚀的痕迹消失，但是由于应力的改变表面出现了多处的凸起.%The C-W co-deposition layer prepared by radio frequency magnetron sputtering was investigated to identify the characteristic of the C-W mixed layers in fusion experimental reactors. Layers were characterized by ion beam analysis (IBA), Raman spectra (RS) and scanning electron microscopy (SEM). It was found that D atoms in C-W layers are mainly trapped by the trapping site of C atoms, only a few of them are arrested by W atoms or defects. D concentration in the C-W layers deposited at 5.0Pa with a fixed flow rate ratio QD2/QAr=2.5 was lower than 10%and decreased slightly with increasing temperature. D concentration increased with the gas pressure from zero to 5 Pa and then decreased from 5 Pa to 10 Pa. RS revealed that the crystal structure of the C-W layers became graphite-like with increasing temperature. SEM images showed that the caves disappeared and convex bodies were dotted on the surfaces as the temperature increased.