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arXiv · 1505.08036

Phase formation, thermal stability and magnetic moment of cobalt nitride thin films

Rachana Gupta·Nidhi Pandey·Akhil Tayal·Mukul Gupta
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Abstract

Cobalt nitride (Co-N) thin films prepared using a reactive magnetron sputtering process by varying the relative nitrogen gas flow (\pn) are studied in this work. As \pn~increases, Co(N), \tcn, Co$_3$N and CoN phases are formed. An incremental increase in \pn, after emergence of \tcn~phase at \pn=10\p, results in a continuous expansion in the lattice constant ($a$) of \tcn. For \pn=30\p, $a$ maximizes and becomes comparable to its theoretical value. An expansion in $a$ of \tcn, results in an enhancement of magnetic moment, to the extent that it becomes even larger than pure Co. Though such higher (than pure metal) magnetic moment for Fe$_4$N thin films have been theoretically predicted and evidenced experimentally, higher (than pure Co) magnetic moment are evidenced in this work and explained in terms of large-volume high-moment model for tetra metal nitrides.

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Rachana Gupta, Nidhi Pandey, Akhil Tayal, Mukul Gupta. 2015-05-29. Phase formation, thermal stability and magnetic moment of cobalt nitride thin films. https://arxiv.org/abs/1505.08036

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