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arXiv · 1402.7209

Annealing-induced enhancement of ferromagnetism and nano-particle formation in ferromagnetic-semiconductor GeFe

Yuki Wakabayashi·Yoshisuke Ban·Shinobu Ohya·Masaaki Tanaka
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Abstract

We report the annealing-induced enhancement of ferromagnetism and nano-particle formation in group-IV-based ferromagnetic-semiconductor GeFe. We successfully increase the Curie temperature of the Ge0.895Fe0.105 film up to ~220 K while keeping a single ferromagnetic phase when the annealing temperature is lower than 500{\deg}C. In contrast, when annealed at 600{\deg}C, single-crystal GeFe nano-particles with stacking faults and twins, which have a high Curie temperature nearly up to room temperature, are formed in the film. Our results show that annealing is quite effective to improve the magnetic properties of GeFe for high-temperature-operating spin-injection devices based on Si or Ge.

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Yuki Wakabayashi, Yoshisuke Ban, Shinobu Ohya, Masaaki Tanaka. 2014-02-28. Annealing-induced enhancement of ferromagnetism and nano-particle formation in ferromagnetic-semiconductor GeFe. https://doi.org/10.1103/physrevb.90.205209

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