Magnetic and Diffusional Properties of Compositionally modulated Amorphous CoTi/CoNb Alloys

Studies to determine the effects of alternating layers of positive-magnetostriction a-CoTi and negative-magnetostriction a-CoNb, to investigate the consequences for the film magnetic properties, and to elucidate the Nb-Ti interdiffusion mechanism, are described. Co
80
Ti
20
/Co
80
Nb
20
and Co
80
Ti
20
/Co
70
Si
15
B
15
films, compositionally modulated with wavelengths of 30 to 60 Å, were prepared by sputtering. The CoTi/CoNb coercivity was found to be increased compared with CoNb, CoTi, and CoNbTi films. The compositionally modulated structure changes to a simple periodic structure through low-temperature heat treatment, but this transition is apparently reversible at higher temperatures through some anomalous diffusion mechanism.