AN X-RAY-DIFFRACTION STUDY OF EPITAXIAL TIN NBN SUPERLATTICES/

X-ray diffraction measurements and simulations were carried out to cha racterize the composition modulation and structure of TiN/NbN superlat tices. A trapezoidal/sawtooth form of the composition wave was assumed . Random d-spacing fluctuations with Gaussian width approximately 0.00 2 nm and layer thickness variations of 0.1-0.5 nm were incorporated to match the observed broadening of the peaks. Best fits to the experime ntal data showed that considerable interdiffusion was present, with up to 15 at.% metal substitution within the layers and interface widths of 0.4-2.0 nm. The interface width values agreed well with those used in hardness enhancement calculations for epitaxial TiN/NbN superlattic es. (C) 1997 Elsevier Science S.A.