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arXiv · 1708.07378

Investigation of thickness dependent composition of boron carbide thin films by resonant soft x-ray reflectivity

P. N. Rao·R. K. Gupta·K. Saravanan·A. Bose·S. C. Joshi·T. Ganguli·S. K. Rai
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Abstract

Boron carbide thin films of different thicknesses deposited by ion beam sputtering were studied. The deposited films were characterized by grazing incidence hard x-ray reflectivity (GIXR), resonant soft x-ray reflectivity (RSXR), x-ray photo electron spectroscopy (XPS), resonant Rutherford backscattering spectrometry (RRBS), and time of flight secondary ion mass spectrometry (TOF-SIMS). An in-depth profile of the chemical elements constitute the films is reconstructed based on analysis of reflectivity curves measured in the vicinity of B K-edge. The composition of films is closely dependent on film thickness. Boron to Carbon (B/C) ratio reaches to ~4 as the thickness of deposited films increases. The B/C ratio estimated from RSXR measurements are in agreement with the RRBS measurements. TOF-SIMS data also suggested that decrease in boron content with decrease in film thickness. XPS measurements confirm the presence of little amount of B atoms on the surface of low thickness film.

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P. N. Rao, R. K. Gupta, K. Saravanan, A. Bose, S. C. Joshi, T. Ganguli, S. K. Rai. 2017-08-24. Investigation of thickness dependent composition of boron carbide thin films by resonant soft x-ray reflectivity. https://arxiv.org/abs/1708.07378

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