Title :
Influence of heat-treatment conditions on the electrical conduction mechanism of grain-boundary in cobalt ferrites
Author :
Na, J.G. ; Kim, M.C. ; Lee, T.D. ; Park, S.J.
Author_Institution :
Korea Inst. of Sci. & Technol., Seoul, South Korea
fDate :
11/1/1993 12:00:00 AM
Abstract :
The electrical resistance and conduction mechanism of the grain-boundary in CoxFe3-xO4 (x=0.94, 0.97, 1.00, 1.03 and 1.06) under various heat-treatment conditions have been characterized, using a complex impedance analysis technique. The electrical resistance of cobalt ferrites decreases with increasing quenching temperature, which is mainly attributed to the decrease of Rgb in Fe-excess cobalt ferrites and Rg in Co-excess ones. It is verified that for the furnace-cooled Co0.94Fe2.06O4, the conduction mechanism of the grain and grain-boundary is n-type and p-type, respectively. For furnace-cooled Co1.06Fe1.94 O4, the conduction mechanism of the grain and grain-boundary is p-type and n-type, respectively. These results indicate that the resistivity in the p-type part of cobalt ferrites decreases more rapidly than that in the n-type part with increasing quenching temperature
Keywords :
cobalt compounds; electrical conductivity of crystalline semiconductors and insulators; ferrites; grain boundaries; quenching (thermal); Co0.94Fe2.06O4; Co1.06Fe1.94O4; CoxFe3-xO4; complex impedance analysis technique; electrical conduction mechanism; electrical resistance; furnace cooled ferrites; grain-boundary; heat-treatment conditions; n-type; p-type; quenching temperature; Cobalt; Conductivity; Electric resistance; Extraterrestrial measurements; Ferrites; Furnaces; Impedance measurement; Network address translation; Resistance heating; Temperature;
Journal_Title :
Magnetics, IEEE Transactions on
