Fabrication of CoNiP Thin Films with Improved Magnetic Property for Application in MEMS

Abstract:

This paper reports on fabricated hard magnetic cobalt nickel phosphorous (CoNiP) films with electro-chemically deposition technique on copper substrate in the presence of different urea (0 to 10 g/L) and NaH₂PO₂ (16 to 21 g/L) concentrations. Thin films were obtained at current density ranges from 5 to 20 mA/cm² and temperature varies from ambient temperature to 60°C. Magnetic properties namely coercivity, remanent magnetization, saturation magnetization and squareness of the films were studied using Vibrating Sample Magnetometer (VSM). The result showed that for bath containing higher concentration of urea (10 g/L), bright films with higher coercivity were obtained at moderate current density (15 mA/cm²) and at higher temperatures (40-60°C). In contrary, uniform and bright films were produced at ambient temperature in bath containing no urea or lower concentration of urea. Scanning Electron Microscopy (SEM) revealed that porosity and cracking tendency are increased with increasing temperature. CoNiP thin films with improved magnetic properties are thus obtained for plausible applications in high density recording media and MEMS.

• Periodical: Applied Mechanics and Materials (Volume 860)
• Pages: 87-92
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.860.87
• Online since: December 2016
• Authors: Mobashera Saima Haque*, M.F. Rahman, M.M. Zaman, M.A. Matin, A.K.M.A. Hakim, M.F. Islam
• Keywords: CoNiP Thin Film, Electro-Deposition, Magnetic Properties

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