Title :
Magnetic properties and interaction effect in sputtered Nd2 Fe14B films
Author :
Tsai, J.L. ; Huang, E.Y. ; Chin, T.S. ; Chen, S.K.
Author_Institution :
Dept. of Mater. Sci. & Eng., Tsing Hua Univ., Hsinchu, Taiwan
fDate :
9/1/1997 12:00:00 AM
Abstract :
Nd2Fe14B/Ta bilayers with individual layer thickness between 40-400 nm have been grown on Si(111) and polycrystalline alumina substrates, respectively, by dc magnetron sputtering. The coercivity of Nd2Fe14B film increases with increasing Ta thickness. Room temperature coercivity of 7-10 kOe was routinely obtained with Ta underlayer thicknesses greater than 40 nm. Exchange coupling among Nd2Fe14B nanocrystalline grains in the hard magnetic layer with higher coercivity was studied by the Henkel plot, which shows positive and large deviation from the linear Wohlfarth relationship, depicting strong coupling among Nd2Fe14B nano-grains
Keywords :
coercive force; exchange interactions (electron); ferromagnetic materials; interface magnetism; iron compounds; magnetic thin films; nanostructured materials; neodymium compounds; permanent magnets; sputtered coatings; tantalum; 20 C; 40 to 400 nm; Henkel plot; Nd2Fe14B film; Nd2Fe14B nanocrystalline grains; Nd2Fe14B-Ta; Nd2Fe14B/Ta bilayers; Si(111); Ta thickness; Ta underlayer thickness; coercivity; dc magnetron sputtering; exchange coupling; hard magnetic layer; interaction effect; linear Wohlfarth relationship; magnetic properties; nano-grains; polycrystalline alumina substrates; room temperature coercivity; sputtered Nd2Fe14B films; strong coupling; Coercive force; Iron; Magnetic films; Magnetic properties; Neodymium; Remanence; Semiconductor films; Substrates; X-ray diffraction; X-ray scattering;
Journal_Title :
Magnetics, IEEE Transactions on
