Effect of the TiN content in the Pd-TiN seed layer on the microstructure and magnetic properties of Co/Pd multilayered media

Abstract

[Co(0.2 nm)/Pd(0.8 nm)](20) multilayered films on 15 nm Pd-TiN seed layers were fabricated by dc magnetron sputtering without heating the substrate. The effects of TiN content on microstructure and magnetic properties of the [Co/Pd] multilayered media were studied. By increasing the TiN content in the Pd-TiN seed layer to an optimum level, coercivity of the [Co/Pd] multilayered media increased to 6.7 kOe. However, further increase of TiN content beyond 22 vol % reduced coercivity (Hc), implying that there exists a critical TiN concentration to enhance the magnetic property of the [Co/Pd] multilayered media. Transmission electron microscopic observations revealed that well-isolated [Co/Pd] multilayered grains with apparent grain boundaries were achieved by controlling the TiN content in the Pd-TiN seed layer. The average grain diameter was 8 nm with a dispersion of 11.2%, grown on the Pd-TiN seed layer with TiN content of 22 vol %. (C) 2011 American Institute of Physics. [doi:10.1063/1.3554205]