Inhomogeneous distribution of manganese atoms in ferromagnetic ZnSnAs2:Mn thin films on InP revealed by three-dimensional atom probe investigation

Atomic-scale Mn distributions in ferromagnetic ZnSnAs2:Mn thin films grown on InP substrates have been studied by applying three-dimensional atom probe (3DAP) microscopy. It is found that Mn atoms in cross-sectional 3DAP maps show the presence of inhomogeneities in Mn distribution, which is characte...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of applied physics 2015-05, Vol.117 (17)
Hauptverfasser: Uchitomi, Naotaka, Inoue, Hiroaki, Kato, Takahiro, Toyota, Hideyuki, Uchida, Hiroshi
Format: Artikel
Sprache:eng
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:Atomic-scale Mn distributions in ferromagnetic ZnSnAs2:Mn thin films grown on InP substrates have been studied by applying three-dimensional atom probe (3DAP) microscopy. It is found that Mn atoms in cross-sectional 3DAP maps show the presence of inhomogeneities in Mn distribution, which is characteristic patterns of a spinoidal decomposition phase with slightly high and low concentration regions. The high Mn concentration regions are expected to be coherently clustered MnAs in the zinc-blende structure, resulting in the formation of Mn-As random connecting patterns. The origin of room-temperature ferromagnetism in ZnSnAs2:Mn on InP can be well explained by the formation of atomic-scale magnetic clustering by spinoidal decomposition without breaking the continuity of the zinc-blende structure, which has been suggested by previous theoretical works. The lattice-matching between magnetic epi-layers and substrates should be one of the most important factors to avoid the formation of secondary hexagonal MnAs phase precipitates in preparing ferromagnetic semiconductor thin films.
ISSN:0021-8979
1089-7550
DOI:10.1063/1.4914065