High B/sub s/ low H/sub c/ CoNiFe films with bcc single-phase structure for write head

Summary form only given. Recent increases in magnetic recording density have been achieved using a high saturation flux density (B/sub s/) material for a write head. A previous report by Osaka et al. (1998) indicates that electroplated CoNiFe films with a mixed structure of body-centered cubic (bcc) and face-centered cubic (fcc) crystals have a high B/sub s/ and a particularly low coercivity (H/sub c/). This CoNiFe film with mixed crystal structure has a large amount of internal stress, and therefore it is difficult to obtain a thick film. In contrast, a low-stress thick film with a high Bs can be obtained with a bcc single-phase crystal structure. However, it is difficult to obtain a low H/sub c/ because of large magnetocrystalline anisotropy. We investigated a high-Bs, low-H/sub c/ CoNiFe film with a bcc single-phase crystal structure and fabricated write heads for high-density recording.