Lattice-matching consideration in pseudo-AFC structure

Pseudo-antiferromagnetically coupled (AFC) structure media are fabricated by replacing the ferromagnetic layers adjacent to the Ru layer with nonferromagnetic layers in the AFC media. Lattice mismatching is manipulated by changing Ru to RuCo(Cr) alloys. The medium without Ru shows narrower PW50 and higher signal-to-noise ratio (SNR) than the pseudoAFC medium with Ru. After replacing Ru with RuCo or RuCoCr, the PW50 and SNR are nearly constant when the thickness of Ru alloy is in the range of 0 to 8 A. X-ray data show that better Co (11.0) texture is found in the pseudo-AFC media with Ru alloy layer than Ru layer. Transmission electron microscope images indicate that the Ru layer enlarges the grain and broaden its distribution.