Open AccessCrystallization of Si3N4 and superhardness effect of ZrN/Si3N4 nano-multilayers
Author(s) -
Wei Zhao,
Dong Yun-Shan,
Jianling Yue,
Geyang Li
Publication year - 2007
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.56.459
Subject(s) - materials science , microstructure , amorphous solid , crystallization , transmission electron microscopy , layer (electronics) , sputtering , high resolution transmission electron microscopy , composite material , diffraction , thin film , crystallography , chemical engineering , nanotechnology , optics , chemistry , physics , engineering
The crystallization behavior of Si3N4 modulation layers in the multilayers and its influences on the microstructure and mechanical properties of ZrN/Si3N4 multilayers were studied. ZrN/Si3N4 multilayers with different Si3N4 thickness were synthesized by reactive magnetic sputtering. The microstructure of the multilayers was characterized with X-ray diffraction and high-resolution transmission electron microscopy, and a nanoindentor was introduced to measure their mechanical properties. The results show that when the thickness is less than 0.9 nm, Si3N4, normally amorphous in the deposited state, could form a NaCl-type pseudocrystal structure due to the template effect of ZrN crystal layer. Crystallized Si3N4 layers and ZrN template layers grow epitaxialy into columnar crystals. Correspondingly, the hardness of the films was enhanced, showing a superhardness effect. Further increasing Si3N4 layer thickness, the coherent interfaces of the multilayers were damaged and Si3N4 layers become amorphous, accompanied by the decline in the hardness of the films.