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

摘要

[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 %.