Medium noise and grain size analysis of CoCrPt/Ti perpendicular media with NiAl seed layer

Perpendicular medium with an average grain size of 8.2 nm have been produced by using a-CoCrPt/Ti/NiAl tri-layer structure. The signal-to-noise ratio for the tri-layer medium is 2-7 dB higher than CoCrPt/Ti bi-layer medium at low deposition temperatures. The medium noise is dominated by dc noise and exhibits little transition noise for densities less than 500 kFCI. The ultra-small grain size will improve the performance of perpendicular media for future high-density recording applications.