In:
Solid State Phenomena, Trans Tech Publications, Ltd., Vol. 215 ( 2014-4), p. 167-172
Abstract:
Solid-state reactions between Ge and Mn films are systematically examined using X-ray diffraction, photoelectron spectroscopy and magnetic measurements. The films have a nominal atomic ratio Ge:Mn = 40:60 and are investigated at temperatures from 50 to 500 °С. It is established that after annealing at ~120 °С, the ferromagnetic Mn 5 Ge 3 phase is the first phase to form at the 40Ge/60Mn interface. Increasing the annealing temperature to 500 °С leads to the formation of the ferromagnetic phase with a Curie temperature T C ~ 360 K and magnetization M S ~ 140-200 emu/cc at room temperature. Analysis of X-ray diffraction patterns and the photoelectron spectra suggests that the increased Curie temperature and magnetization are related to the migration of C and O atoms into the Mn 5 Ge 3 lattice and the formation of the Nowotny phase Mn 5 Ge 3 С x O y . The initiation temperature (~120 °С) of the Mn 5 Ge 3 phase is the same both for solid-state reactions in Ge/Mn films, as well as for phase separation in Ge x Mn 1-x diluted semiconductors. We conclude that the synthesis of the Mn 5 Ge 3 phase is the moving force for the spinodal decomposition of the Ge x Mn 1-x diluted semiconductors.
Type of Medium:
Online Resource
ISSN:
1662-9779
DOI:
10.4028/www.scientific.net/SSP.215
DOI:
10.4028/www.scientific.net/SSP.215.167
Language:
Unknown
Publisher:
Trans Tech Publications, Ltd.
Publication Date:
2014
detail.hit.zdb_id:
2051138-3
