Recording properties of CoCrPt tape media sputter-deposited at room temperature on polymeric substrates

Recording properties of CoCrPt thin films sputter-deposited on polymeric substrates at room temperature were investigated. Typical frequency spectra of the readback signal from sputtered tapes at various recording densities revealed an appreciable amount of modulation noise, despite the fact that the sputtered tape is expected to be smooth and conformal with the substrate. Atomic force microscopy images suggest the modulation noise, present as side bands about the signal peak, is primarily due to the roughened polymeric substrate. The nonlinear partial erasure method was used to measure the sharpness of recorded transitions via the frequency domain one-dimensional/ three-dimensional method. Intertransition interactions occurred at a linear density of 130 kfci, which corresponds to a transition length parameter (pa) of 195 nm. This rather large value of transition length is attributed to exchange coupling between grains in the media, suggesting inadequate Cr segregation due to the low-temperature deposition needed to avoid substrate damage. © 2003 American Institute of Physics. @DOI: 10.1063/1.1557335#