| 摘要 |
PURPOSE:To prevent the change in a gap length, by using a material with less water deformation for one of upper and lower magnetic substance layers constituting a core of a magnetic head, using a material possible for control with good accuracy for track width for another and running a medium froem a layer with less wear deformation to another layer. CONSTITUTION:On upper and lower cores of a thin film magnetic head, e.g., a substrate 8, a lower magnetic substance layer 4 is formed by using a ''Supersendust '' having larger specific permeability, saturated magnetic flux density and hardness (>=500 in Vickers hardness). On the other hand, an upper magnetic substance layer 5 is formed with the width equal to a track width TW by using ''Dermalloy ''-plated film having large specific permeability and saturated magnetic flux density, with ease of processing for accurate core shape, not taking the hardness into account. Thus, with narrow interval Dh between a recording medium 10 and a magnetic head, the reduction in the recording and reproducing efficiency can be prevented by preventing that the magnetic substance caused with wear of the recording medium 10 slid toward the arrow 11 covers upper and lower insulating layers 9c and 9d of the gap so that the gap length Lg is narrowed. |
