Effect of annealing temperature on exchange stiffness of CoFeS thin films

We investigate the exchange stiffness constants of 28-nm-thick CoFeB film using Brillouin light scattering. Series of CoFeB films are prepared on the MgO(001) substrate with or without additional 5-nm thick MgO buffer layer, the effect of the annealing temperature on the exchange stiffness constants are studied. We found that the exchange stiffness constant of 400 degrees C annealed sample with MgO buffer increased by 10% form the 200 degrees C annealed sample (-0.73 + 0.01 x 10(-11) J/m), while the exchange stiffness constant of without MgO buffer layer sample increase by 6% from the as-grown sample (=1.11 + 0.02 x 10(-11) J/m). (C) 2015 Elsevier B.V. All rights reserved.