摘要
为了研究纳米多层薄膜的超硬效应 ,采用反应溅射法制备从 1 4nm至 2 7nm不同调制周期的一系列TiN/NbN纳米多层膜。高分辨电子显微镜对薄膜的调制结构和界面生长方式的观察发现 ,TiN/NbN膜具有很好的调制结构 ,并呈现以面心立方晶体结构穿过调制界面外延生长的多晶超晶格结构特征。显微硬度测量表明 ,TiN/NbN纳米多层膜存在随调制周期变化的超硬效应。薄膜在调制周期为 8 3nm时达到HK39 0GPa的最高硬度。分析认为 ,两种不同晶格常数的晶体外延生长形成的交变应力场 ,对材料有强化作用 。
A series of TiN/NbN nano multilayers with various modulation periods were grown by reactive sputtering to understand their super hardness effect of the films.The modulated structures,interfacial structures and growth as well as the micro hardness of the nano multilayers were studied with high resolution transmission electron microscopy and microhardness tester.The results show that the TiN/NbN multilayers have well refined modulation structures and the fcc polycrystalline grains grow epitaxially through the modulated interfaces.Anomalous microhardness was observed,which depends on the modulation periods and peaks at a specific modulation period of Λ =8 3 nm,with a hardness of HK39 0GPa.We suggest that the alternating stress field,induced by lattice mismatch in the hetero epitaxial growth of the multilayers,may account for the superhardness observed.
出处
《真空科学与技术》
CSCD
北大核心
2002年第4期313-316,共4页
Vacuum Science and Technology
