ELECTRON-TRANSPORT PROPERTIES OF NI AND CR THIN-FILMS

The change in resistivity as a function of temperature and the magneto resistivity of Ni and Cr thin films with thicknesses of 300, 500 and 1 000 Angstrom were studied using a four probe technique. It was determi ned that Ni exhibits anistropic magnetoresistance which is typical of ferromagnetic systems. However, an unexpected region of positive magne toresistivity occurred in all the Ni samples when the magnetic held wa s oriented perpendicular to the current but in the plane of the sample . The presence of this positive magnetoresistivity in Ni films implies that interlayer-coupling is not responsible for the similar positive magnetoresistivity behavior observed recently by other workers in Ni/C u multilayers. Analysis of the magnetoresistivity for Cr samples indic ates that the 500 and 1000 A samples are antiferromagnets. The 300 A s ample, however, showed an unusual magnetic behavior and further study of this sample is necessary to accurately characterize its magnetic st ate. (C) 1998 Elsevier Science B.V. All rights reserved.