Si含量对NbN/CrSiN纳米多层膜微观结构和力学性能的影响

摘要

The NbN and CrSiN layers were alternately deposited on the Si substrates by using magnetron sputte-ring apparatus.A series of NbN/CrSiN nano-multilayered films with different Si contents were produced by u-sing different Si contents.By X-ray diffractometry (XRD),scanning electron microscopy (SEM),high resolu-tion transmission electron microscopy (HRTEM)and nano-indentation techniques,the influences of Si content on microstructure and mechanical properties of the NbN/CrSiN nano-multilayered films were investigated.The results indicate that with the increase of Si content,the crystallinity of the film firstly increases and then decrea-ses,as well as the hardness and elastic modulus of the film.When the n(Si):n(Nb)ratio is 3:22,the maxi-mum hardness and elastic modulus are obtained to be 31.92 and 359.3 GPa respectively.The microstructural characterization shows that when the n(Si):n(Nb)ratio is 3:22,the CrN/TiSiN nano-multilayered film presents the columnar growth feature.The CrSiN layers are fully transformed into fcc structure under the tem-plate effect and grown epitaxially with NbN layers.The improvement of the mechanical properties of the NbN/CrSiN nano-multiayered films can be attributed to the coherent and epitaxial growth between CrSiN and NbN layers.%采用磁控溅射工艺在Si底片依次沉积NbN、CrSiN纳米层,通过改变靶材的Si含量,制备出一系列NbN/CrSiN纳米多层膜.分别采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、高透射电子显微镜(HR-TEM)和纳米压痕仪研究Si含量对NbN/CrSiN纳米多层膜显微结构和力学性能的影响.实验结果表明,随着Si含量的增加,NbN相的结晶程度先增加后降低,薄膜的硬度和弹性模量也是先增高后降低,在n(Si):n(Nb)=3:22时获得最高硬度和弹性模量,分别为31.92和359.3 GPa.显微结构表征表明,当n(Si):n(Nb)=3:22时,NbN/CrSiN纳米多层膜柱状晶生长状况最好,CrSiN层在NbN层的模板作用下转变为面心立方结构,并与NbN层呈共格外延生长.薄膜力学性能的提高主要与CrSiN与NbN形成的共格外延生长结构有关.