We have measured the 1/f noise in polycrystalline films of Al, Al-Si(1'/o), and Al-Cu(4'/o) in the temperature range of 300 to 600 K. The temperature dependence indicated activation energies of 0.69, 0.80, and 0.89 eV, respectively. These energies are similar to the activation energies found for Al diffusion along grain boundaries for films of the same size and composition measured in the same temperature range. Measurements of samples with identical compositions but differing widths and thicknesses revealed significant departures from the usual inverse volume dependence of the 1/f noise. PACS numbers: 72.70.+m, 73.60.Dt The origin of 1/f noise in metal films remains one of the longest-standing unanswered questions of solid-state physics. The details of the microscopic source of the noise remain elusive despite its almost universal presence in all metal films. An empirical expression for the 1/f-noise power, Sz, of a currentbiased metal film obtained by Hooge' in 1969 iswhere V is voltage across the sample, 0 is the sample volume, f is the frequency of measurement, and o. is an empirical parameter. Since the 1/f noise in metal films has been shown to be a fluctuation of the sample resistance, 2 the quantity Sz/V2 is independent of the current bias. Hooge originally postulated that the parameter o. was constant for a11 samples; however, many recent experiments have shown this parameter to be temperature and sample dependent. Detailed measurements of the frequency exponent of the noise have verified that the exact exponent is seldom exactly -1 (or 1/f) but is also a function of temperature and sample.Dutta and Horn proposed that the 1/f noise in a metal film results from thermally activated processes and demonstrated that the noise and frequency exponent when measured as a function of temperature can be used to measure the average activation energy and the width of the distribution of activation energies,The questions of what is activating and where still remain unanswered.We report in this paper the first systematic measurements of the temperature dependence of the 1/f'noise in polycrystalline thin films of Al, A1-Cu, and Al-Si alloy. Additions of Cu or Si to an Al film increase the activation energy for A1 atomic motion along grain boundaries6 in the films but not the activation energy for Al motion in the bulk of a grain. 7 We measured a corresponding increase in the activation energy of the

The wall motion coercive force Hc and the rotational coercive force Hr of thin electroplated nickel-iron films are studied as a function of film roughness. Three types of roughness are considered : the first, periodic with a wavelength large compared to a domain wall width and an amplitude small compared with the film thickness; the second, of the order of size of a domain wall; and the third, a substrate roughness that is large compared to the film thickness. H c was found to be related to film thickness according to Hc = CsD+n. This observation was predicted by Néel, except that his assumption of a form of roughness only of the first kind led to a single value for n of −43. Electron micrographs showed that roughness of the second kind increased with film thickness, indicating that n depends on this factor. Roughness of the third kind, as introduced by unidirectional polishing, results in an increase of Cs, while n and Hr are not affected. This third type of roughness was observed to orient the easy magnetic axis parallel to the polishing grooves.

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Argon is commonly used as the sputtering medium for RF sputtering of insulators and is entrapped in the deposits. X-ray emission determination of argon in RF sputtered SiO2 was required as part of a study of the relationships between argon concentration in the deposits and their electrical and physical properties.Concentrations ranging from 0.05 to 7.4 weight % argon were measured in deposits 0.5 to 5μ thick. Two techniques were used for standardization: (1) weight loss of deposits heated for several hours in a helium atmosphere at 600°C; (2) potassium Kα and chlorine Kα measurements on a KCl film of known thickness to infer argon mass/argon Kα net counts. Calibrations made using these procedures agreed to within 10% and are reliable to about ±25% on an absolute basis. Absorption of radiation by the deposits was taken into account and used to correct measured argon intensities for absorption.Sputtering parameters which had major effects on argon concentration were the substrate temperature and the magnetic field applied during sputtering. Argon pressure and RF power were found to have lesser effects.

Coercive forces (He) of Fe–Ni films were observed to depend on thickness, Fe/Ni ratio, and preferred crystal orientation in accordance with predictions based on the Behringer–Smith model. Annealing induces marked crystal growth and orientation of [111] axis normal to the plane in the Ni-rich films (> 80% Ni), but only moderate growth in the Fe-rich (< 80% Ni) films. He for Ni-rich films increases markedly while He for iron-rich films decreases slightly due to annealing. Variations of the anisotropy field, Hk, due to applied stress, indicate that reduction of He for the Fe-rich films results from moderate crystal growth while the increase of He for the Ni-rich films is due to the preferred orientation.