Permeability measurements of permalloy films with a broad band stripline technique

Extrinsic contribution to Gilbert damping in sputtered NiFe films by ferromagnetic resonance

“…However, the increase is surprisingly large. In part, this is because we use the L only model [13] to find m 00 . This model overestimates the amplitude of m 00 , but generally gives peak positions and linewidths close to that of the better RLC model [14].…”

Influence of the electrical resistivity of a ferromagnetic thin film on its permeability measurement performed with a permeameter

“…3. Moraitakis et al [10] have also observed this result on Permalloy thin films deposited on Si substrates. In fact, the resonance frequency of the cell, loaded with the magnetic sample, is reduced by 8% in comparison with the value corresponding to the empty coil.…”

“…Moreover, the interaction between E and the dielectric thick substrate is considered within the determination of RLC parameters for all these three different preliminary measurements. This original approach drastically improves the accuracy of this method to characterize ferromagnetic thin films in comparison with a mere computation of RLC constants from a preliminary measurement performed on the empty cell [10]. In order to validate our method, the permeability shown in Fig.…”

“…On the contrary, the permittivity e of thick substrates contributes to an additional interaction with the electric field E of the TEM mode. A recent work [10] clearly exhibits that the permeability of a 0.15 mm thick film of Permalloy, deposited on a 0.5 mm thick substrate, is deeply affected by the change of the effective dielectric constant of the filled coil for frequencies above 2 GHz. Meanwhile, in both cases the interaction between the electric field and the ferromagnetic film is not considered.…”

A new strip line broad-band measurement evaluation for determining the complex permeability of thin ferromagnetic films

“…Two-port measurement techniques require a more complex set-up and calibration procedure than one-port methods. The latter have been developed in recent years [11,12]. The one-port permeability measurement is based on the modelling of network impedance containing a strip line.…”