| 摘要 |
PURPOSE:To obtain a magnetic film pattern virtually free of superficial unevenness consisting of Fe3O4 and gamma-Fe2O3 on a base substrate by utilizing the difference of magnetic behavior between different Fe oxides. CONSTITUTION:An alpha-Fe2O3 film 6 is formed by reactive sputtering in an Ar plasma and O2 atmosphere on the surface of a ceramic substrate 5, which is followed by the formation of a Cr film, on said film 6, to be photo-etched into a mask pattern 7. The entirety is then accommodated in a reducing furnace containing H2 where it is heated for about 1 hour, whereby the alpha-Fe2O3 film 6 not covered by the mask pattern 7 is reduced into an Fe3O4 film 8. The mask pattern 7 is removed by using an alkaline water solution of potassium ferricyanide. Thus, a permanent magnet film pattern is formed composed of an Fe3O4 film 8 in the alpha-Fe2O3 film 6. Heating follows at approximately 350 deg.C for 1 hour in the air for the oxidation of the Fe3O4 film 8 into a gamma-Fe2O3 film 9, for the realization of a permanent magnet film pattern, with its surface virtually free of unevenness, wherein a gamma-Fe2O3 film 9 is interwoven with an alpha-Fe2O3 film 6. |
