ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
Films of 12 Fe/(Ag–Cu) bilayers were prepared to have either granular or multilayer structures on glass substrates with a 50 A(ring) Cu buffer layer. A magnetic Fe layer of 15 A(ring) was deposited by e-beam evaporation, and a nonmagnetic Ag–Cu layer of 20 A(ring) by thermal coevaporation with various Ag/Cu ratio. As the nonmagnetic layer composition changed from Ag to Cu, roughness of the film surface varied from more than 100 A(ring) to less than 10 A(ring), measured with atomic force microscopy. Regularity of multilayer structure was evident in the Fe/Cu film from a superlattice peak at around 2theta=2.5 deg by Cu Kα x-ray diffraction. The peak weakened as the Ag content increased in the nonmagnetic layer, and completely disappeared at Ag/Cu(approximately-greater-than)1, which indicated that granular structure became dominant. Pendelloesung peaks at 2theta=1 to 2 deg had a similar composition dependency. The structural change was confirmed with cross-sectional transmission microscopy, too. The deposited structure is explained in terms of surface tension and wettability of each element. Increasing Cu content decreases the surface tension and increases the wettability of the nonmagnetic layer. Heat treated film structures are explained with identical terms. Change of magnetoresistance is discussed in part by connectivity of the nonmagnetic layer. From the discussion, a reasoning is given to the effect of annealing on the magnetoresistance of the films. © 1996 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.362043
