Track width study of E-beam defined GMR read heads on longitudinal and perpendicular media

The track width performance of giant magnetoresistive (GMR) read heads defined by e-beam lithography was studied in a series of recording tests. Results on longitudinal media showed slow reductions of magnetic versus physical read widths below 100 nm due to spacing loss effects and substantial microtrack widths. These findings led to explorations of different measurement techniques to address the microtrack width issue. Results on perpendicular media showed distinctly narrower magnetic read widths consistent with modeling results assuming negligible microtrack widths. This read width narrowing effect could be another potential advantage for perpendicular media in high density recording. Finally, various parametric effects on track width performance were also explored and compared between perpendicular and longitudinal media.