Magnetic behavior of atomically engineered NiO–Co–Cu-based giant magnetoresistance spin valves using Pb as a surface modifier

Diffusion and segregation of substrate copper in electrodeposited Ni–Fe thin films

“…For example, the Cr and Mo reduce the Cu segregation as we reported elsewhere [45]. In fact, Cr and Mo are effective materials for protecting of the surface oxidation [17,46] and so Cu segregation decreases [13]. Also after air exposure, less induced Cu segregation occurs for deposits containing the Cr and Mo.…”

“…There are some reports on diffusion, segregation and accumulation of copper for thin films produced by vacuum deposition [12][13][14][15][16][17]. The presence of small amounts of the Cu inside the magnetic layer has a negative effect on magnetic properties [18,19].…”

“…For example, one monolayer of Bi on the Cu layer prevents surface segregation and increases magnetic sensitivity of the Ni-Fe layer [12]. Similarly, Pb controls the Cu segregation by out diffusion and segregation to surface [14,17].…”

Surfactant controlled interfacial alloying in thermally evaporated Cu/Co multilayers

“…It is reported in the literature that metastable structure of a mixed CuCo phase may exist at the interfacial regions in Cu/Co thin film multilayers [1][2][3]. In case of Cu/Co multilayers, growth of Co-on-Cu is thermodynamically unfavorable because Co > Cu [4]. In an earlier study it was found that Co make islands over Cu while Cu makes a smooth layer when deposited on Co [5].…”

The influence of the nonmagnetic metal spacer Bi, Ag and Cu on the properties of the multilayer films

“…Surface-active atoms can float out to the surface when the atoms with higher surface free energy are deposited on the atoms with the lower surface energy to decrease the total surface and interface energy in the system. In Chopra's paper, the free energy of Bi, Ag and Cu, which are 0.3282, 1.246, 2.30 J/m 2 , are significantly lower than that of Ni and Fe, which are 2.364 and 2.939 J/m 2 , respectively [18] . Therefore, it is thermodynamically reasonable that the segregation of Bi, Ag and Cu atoms is on the NiFe surface.…”