An Investigation into the Effects of Substrate Temperature on Magnetic Properties of RF Sputtered NiFe Films

Abstract:

The paper describes results of investigation on sputtered NiFe Films to determine the sputter deposition condition that could produce magnetic field sensors with the desired magnetic properties. The magnetic materials used in such devices should have a low coercive force, a low anisotropy field and a low magnetization dispersion, α50. .The results of systematic investigation of radio-frequency (RF) sputtered, RF biased, 82-18 % NiFe films showed (i) Improved Kobelev methods were applied to magneto-optic measurement techniques, suppress the magnetization ripples when subjected under the application of dc field. (ii) Anisotropy field results indicated an inverse trend with increasing substrate temperature (iii) the experimental measurements on magnetization dispersion relatively constant up to 200 °C with α50 approximately 1.2°, it then increases more sharply to about 3.5° at 400 °C substrate temperature. The work also provide understanding of the effects on the magnetic properties of sputtered magnetic films that is very limited as current literature is almost entirely limited to evaporated magnetic films.

• Periodical: Key Engineering Materials (Volume 442)
• Pages: 109-115
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.442.109
• Online since: June 2010
• Authors: Pervez Akhtar, T.J. Ali, R. Mahmud
• Keywords: Anisotropy Field, Coercive Force, Magnetic Thin Film, Magnetization Dispersion, Magnetoresistivity MR, RF Sputtering, Substrate Temperature

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