| 摘要 |
PURPOSE:To improve reliability without the generation of the exfoliation between a nonmagnetic base and thin magnetic film by using a ceramic compsn. which is expressed by the general formula xNa2O.yNb2O5 and of which the compsn. range is specified as the nonmagnetic base. CONSTITUTION:The Na2O-Nb2O5 ceramic compsn. has th-compsn. expressed by the general formula xNa2O.yNb2O5 and the compsn. range thereof is set at 0.74<=x/y<=1.00 by which the coefft. alpha of linear expansion of the above- mentioned ceramic compsn. is controlled to 130-160X10<-7>/ deg.C. The form of the ceramic compsn. to be used for the nonmagnetic base 1 may be either of a sintered body or single crystal. A signal conductor 4 is formed via an insulat ing layer 3 formed of SiO2, etc. in a lower magnetic film 2. The signal conductor 4 is formed by etching the thin copper film, etc. deposited and formed by, for example, a method such as sputtering and is so disposed as to supply a record ing or reproducing signal into the closed magnetic circuit constituted of the lower magnetic film 2 and upper magnetic film. |
