摘要
采用脉冲激光沉积(PLD)法在不同直流负偏压下烧蚀石墨靶材,在单晶Si片上沉积CNx薄膜。利用X射线光电子能谱(XPS)、Raman光谱和扫描电子显微镜对薄膜的化学成分、价键状态、表面形貌进行了表征,并借助于涂层附着力自动划痕仪和纳米压痕仪分别测试了膜–基结合力及薄膜硬度。结果表明:偏压辅助PLD技术显著提高了薄膜的氮含量,膜–基结合力和沉积速率分别随着负偏压值单调增加和减少。结合XPS和Raman分析得出:当偏压Vb=–40 V时,价键摩尔含量x(sp3)和x(sp3)C—N达到最大值及D峰与G峰强度比ID/IG达到最小值(2.2)。薄膜中sp3杂化键比例的提升有助于CNx薄膜构建类金刚石结构和网状结构且薄膜硬度与x(sp3)和x(sp3)C—N值的变化呈现出了正比例关系。
CNx films were deposited on monocrystal silicon substrates via pulsed laser deposited （PLD） ablation of graphite target at different DC negative bias voltages. The chemical compositions, valence bonding state properties and surface morphology of the films were investigated by X-ray photoelectron spectroscopy （XPS）, Raman spectroscopy and scanning electron microscopy, respec-tively. The adhesion strength between the film and the substrate and the hardness of the films were determined by scratch tests and a nano indentation method. The results show that the nitrogen content of the films can be improved by the bias voltage assisted PLD technique. The adhesion strength increases and the deposition rate decreases as the bias voltage increases. According to the analysis of XPS and Raman, valence bond molar content x（sp3） and x（sp3）C-N is the maximum value, and ID/IG （i.e., the integral intensity ratio of D peak to G peak ） is the minimum value of 2.2 at the bias voltage of-40V. The increased percentage of sp3 hybridization bonding can be contribute to the diamond-like and network structures. The hardness of CNx films is proportional to the values of x（sp3） and x（sp3）C-N.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2013年第9期1265-1270,共6页
Journal of The Chinese Ceramic Society
基金
浙江省自然科学基金(Y4110645)资助项目
关键词
氮化碳薄膜
脉冲激光沉积
组织结构
机械性能
偏压
carbon nitride thin film
pulsed laser deposition
microstructure
mechanical property
bias voltage
