荧光XAFS研究超硬TiN/Si3N4多层膜的界面效应

Fluorescence x-ray absorption fine structure (XAFS) and x-ray diffraction (XRD) are used to study the structures of super-hard TiN/Si3N4 multilayer films deposited by reactive magnetron sputtering at temperatures of 20, 200, 500 and 800 °C. The resultsclearly reveal the presence of interfacial intermixing between adjacent TiN and Si3N4 layers. And the interlayer is composed of TiSixN1-x solid solution with a NaCl-like structure. Increasing the growth temperature from 20 to 500 oC, the crystalline quality of pure TiN layer improves significantly, and the thickness of interlayer rises from 2.5 to 5.0 A. For the TiN/Si3N4 multilayer film grown at 800 oC, the interfacial layer is composed of TiSi0.3N0.7 solid solution and reaches the thickness of 7.8 A, where the Ti-N bond length (2.06 A) is significantly shrunk as compared with the value (2.12 A) in the pure TiN layer. We propose that the TiSixN1-x interlayer with obviously contracted Ti-N bond length is an important hardening factor for the crystalline/amorphous TiN/Si3N4 multilayer films grown at high temperatures.