  The effect of annealing under a magnetic field on the microstructure and
properties of YNixMn1-xO3 (x=0.33 and 0.5) films has been investigated. It is
found that the ferromagnetic transition temperature is significantly enhanced
after post annealing in the presence of an 8 T magnetic field. Characterization
study shows that the microstructure is affected, obtaining larger grains of
uniform size when films are annealed under a magnetic field. The improvement in
the ordering temperature of all films is interpreted in terms of the grain
growth caused by the magnetic-field driving force for boundary motion where the
exchange coupling is high.
