A High Throughput Study of both Compositionally Graded and Homogeneous Fe-Pt Thin Films

TL;DR

This study systematically investigates the magnetic properties of Fe-Pt thin films with varying compositions and annealing conditions, establishing a high throughput method to optimize coercivity for potential device integration.

Contribution

It introduces a high throughput approach combining compositional mapping and magnetic characterization to optimize Fe-Pt thin film properties.

Findings

Maximum coercivity depends on composition and annealing conditions.

L10 FePt phase formation correlates with increased coercivity.

High throughput mapping effectively identifies optimal processing parameters.

Abstract

Compositionally graded Fe-Pt thin films were prepared on stationary 100 mm Si substrates by magnetron sputtering a base target of Fe on which a piece of Pt is asymmetrically positioned. Energy Dispersive X-Ray analysis was used to map the variation in film composition across the substrate, as a function of the size of the Pt piece. A scanning polar Magneto-Optical-Kerr-Effect system was used to probe the influence of composition and post-deposition annealing conditions (temperature and time) on coercivity. In this way the maximum coercivity achievable for the sputtering system used could be established in a high throughput fashion. The evolution in coercivity with composition was correlated with the formation of L10 FePt and changes in its lattice parameters, as determined by scanning X-ray diffraction. High throughput coercivity mapping was then carried out on homogeneous Fe-Pt thin films of different composition treated to different annealing conditions. This study serves as a step towards the integration of coercive FePt films into collectively fabricated devices.