X-ray reflectivity study of growth characteristics of ion beam deposited NbC thin films

Abstract

NbC films are prepared using ion beam sputtering system by varying Ar flow rate from 2.5 sccm (standard cubic centimeter per minute) to 4.0 sccm. Grazing incidence x-ray reflectivity (λ= 1.54 Å) and soft x-ray reflectivity techniques are applied to characterize the film structure and chemical compositions. The soft x-ray reflectivity measurements are carried out using reflectivity beamline at Indus-1 synchrotron source. The results suggest that the density of the film increases with increase in Ar gas flow. Density of 94.5% bulk value is achieved at Ar gas flow of 4.0 sccm (NbC bulk density is 7.82 g/cc). Optical density profiles in wavelength region of 60-120 Å is obtained from the soft x-ray reflectivity data and that in turn is used to analyze the film composition.