NbSiN纳米复合膜的显微结构、超硬效应和机理的研究  

Synthesis and Characterization of Mechanical Properties of Superhard NbSiN Nanocomposite Coatings

作　　者：陈朋灿 李伟[2] 刘平[2] 张柯[2] 马凤仓[2] 陈小红[2] 何代华[2] 

机构地区：[1]上海理工大学机械工程学院,上海200093 [2]上海理工大学材料科学与工程学院,上海200093

出　　处：《真空科学与技术学报》2016年第6期649-653,共5页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金项目(51471110)

摘　　要：采用NbSi复合靶,通过调节Nb与Si的比例,利用磁控溅射射频工艺,在单晶硅片上沉积不同Si含量的NbSiN纳米复合膜。利用X射线衍射仪、纳米压痕仪和高分辨透射电镜等,研究了Si含量对NbSiN纳米复合膜的微观结构和力学性能的影响。结果表明:随着薄膜中Si含量的增加,其结晶程度先升高,然后降低,硬度和弹性模量先增加后降低,当n(Si):n(Nb)=5:20时,NbSiN薄膜硬度和弹性模量均达到最大值33.6和297.2 GPa。微观组织观察表明,此时NbSiN薄膜内部形成Si_3N_4界面相包裹NbN纳米晶粒的纳米复合结构,Si_3N_4界面相呈结晶态协调相临NbN纳米晶粒间的位向差,并与NbN纳米晶粒之间形成共格外延生长,其微结构可用nc-NbN/c-Si_3N_4模型来表示,表明其超硬效应源于NbN基体相和Si_3N_4界面相之间形成的共格外延生长界面。The NbSiN nanocomposite coatings were deposited by magnetron sputtering the on Si substrate. The influence of the synthesis conditions,including but not limited to the area ratio of Nb and Si of the lab-made NbSi target, Si-content flow-rate, on the microstructures, phase-structures and mechanical properties of the NbSiN coatings was investigated with X-ray diffraction, high resolution transmission electron microscopy and nano-indentation tech- niques. The results show that the Si-content significantly affects the microstructures and mechanical properties. To be specific, as Si-content increased, the crystallinity, hardness, and elastic modulus changed in an increase-decrease mode;grown at a Si/Nb ratio of 5： 20, the strongest hardness and elastic modulus were 33.6 and 297.2 GPa, respec- tively. As shown in HRTEM images, The film formed the nanocomposite structure with NbN nanocrystallites surroun- ded by crystallized Si3N4 interfacial phase, which could be characterized as the crystallized Si3N4 interfacial phase coordinated misorientations between NbN nanocrystallites and grew coherently with them, and denoted by nc-NbN/ c-Si3N4 model,indicating that the superhardness effect resulted from the coherent epitaxial interface between NbN nanocrystallites and Si3N4 interfacial phase.

关 键 词：NbSiN纳米复合膜 显微结构 超硬效应 强化机制 

分 类 号：TG174.4[金属学及工艺—金属表面处理]