Perpendicular magnetic recording is expected to achieve high density recording performance and may be an alternative technology to longitudinal magnetic recording. the thin films of CoCr-based alloy have been regarded as one of the most promising candidates for media in perpendicular magnetic recording with attain high density recording characteristic including remarkable perpendicular magnetic anisotropy and high perpendicular coercivity.
Firstly, sputtering conditions for deposition were optimized in CoCrPt/Ti alloy films. in order to obtain the high perpendicular anisotropy, good c-axis alignment, and high squareness in ternary system.
Serial sample of CoCrPt/Ti alloy films have been fabricated by dc-magnetron co-sputtering with varying the Ti-underlayer thickness, CoCrPt magnetic layer thickness, and Pt composition. The magnetic and magneto-optical properties of these sample have been examined by measuring the Kerr hysteresis loops. optimal PMA represented when Ti thickness is 700Å over, CoCrPt thickness is 400Å under, and Pt content is about 21 at.% over.
Secondly, local coercivity distribution of CoCrPt films has been investigated by measuring the polar Kerr hysteresis loops of the local areas of submicron size using a magneto-optical microscope magnetometer to study the magnetic reversal behavior of CoCrPt alloy films. Interestingly, all sample with varying Pt composition under examination showed Gaussian distribution. that is, CoCrPt represented a random local properties. and local coercivity deviation was decreased with increasing Pt composition for that reason reducing segregation between grains. local coercivity distribution of CoCrPt films with Pt composition variation deviated from Gaussian distribution with increasing Pt composition.
