A study of the magnetic properties and recording characteristics of C/CoCrTa/Cr film media as a function of CoCrTa thickness (t(Co)) is presented. The coercivity (H-c) shows a broad peak around 250 Angstrom, but the B-I delta product decreases linearly with CoCrTa thickness. The signal-to-noise (S/N-m) gives a broad maximum at about 400 Angstrom, corresponding to which the delta M half-peak width derived from the delta M measurement also shows a peak. The overwrite (OW) shows a thickness-independent maximum between t(Co) = 200 and 400 Angstrom. By separating the effects of thickness and coercivity, it was found that H-c determines mainly the S/N-m when t(Co) is below 400 Angstrom. But OW strongly depends on both t(Co) and H-c.