| 摘要 |
PURPOSE:To reduce the contour effect by providing a diffused layer having an ununiform magnetic characteristic on the substrate side of a lower core and the protective layer side of an upper core. CONSTITUTION:A lower core 11 and an upper core 15 consisting of magnetic materials are provided on a substrate 10, and a protective layer 16 consisting of an SiO2 or the like and a protective plate 17 are provided on the core 15. A foundataion layer 18 consisting of Al or the like for formation of the diffused layer is provided on the substrate 10 side of the core 11 and the layer 16 side of the core 15. Since this layer 18 is provided, Al or the like in the layer 18 is diffused in cores 11 and 15 by the heat treatment for improvement of characteristics of a magnetic core to form the diffused layer having an ununiform magnetic characteristic. Thus, a signal reproduced in core end parts is reduced to reduce the contour effect because the diffused layer exists in core end parts where the contour effect occurs. |
