XAFS study of Fe-doped SnO2 annealed samples

A.M. MUDARRA NAVARRO, BILOVOL, V., C.E. RODRÍGUEZ TORRES, F. H. SÁNCHEZ, AND A.F. CABRERA

Campinas, Brasil

Workshop; Reunión Anual de Usuarios LNLS; 2007

LNLS

Understanding the origin of the magnetism in diluted magnetic semiconductors produced by doping non-magnetic semiconductors with transition metal ions is actually a subject ofinterest [1?3]. Most reported models for the observed magnetic behaviour are based on the interaction among magnetic impurities which can be mediated by oxygen or by free carriers.Then, oxygen vacancies may have a great influence on the magnetic properties of these compounds. Coey et al. have observed ferromagnetic behaviour in Fe-doped SnO2 and theyhave proposed that F-center exchange is responsible for the ferromagnetic coupling between Fe ions [4]. Since oxygen vacancy concentration can be modified by adequate thermal treatment, in this work we have studied the Fe local environment in Sn0:9Fe0:1O2 powders produced by ball milling and subjected to annealing under different atmospheres, by x-ray absorption (XAS).