Study of magnetic iron nitride thin films deposited by high power impulse magnetron sputtering

TL;DR

This study compares the structural and magnetic properties of iron-nitride thin films deposited by high power impulse magnetron sputtering and direct current magnetron sputtering, highlighting differences in microstructure and magnetic behavior.

Contribution

It provides a systematic analysis of how different sputtering techniques affect Fe-N film properties, emphasizing the impact of plasma characteristics on nitrogen reactivity and film microstructure.

Findings

HiPIMS films exhibit nanocrystalline, globular microstructure.

HiPIMS films show improved soft magnetic properties.

Nitrogen reactivity is lower in HiPIMS compared to dc-MS.

Abstract

In this work, we studied phase formation, structural and magnetic properties of iron-nitride (Fe-N) thin films deposited using high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (dc-MS). The nitrogen partial pressure during deposition was systematically varied both in HiPIMS and dc-MS. Resulting Fe-N films were characterized for their microstructure, magnetic properties and nitrogen concentration. We found that HiPIMS deposited Fe-N films show a globular nanocrystalline microstructure and improved soft magnetic properties. In addition, it was found that the nitrogen reactivity impedes in HiPIMS as compared to dc-MS. Obtained results can be understood in terms of distinct plasma properties of HiPIMS.