| 摘要 |
PURPOSE:To improve start/stop characteristics by establishing a hold magnetic field with optional intensity by providing a semihard magnetic material layer on a driving pattern. CONSTITUTION:A garnet type magnetic crystal layer is formed on GGG crystal 4 and on a layer 3, an insulating layer 5 is formed; and conductor pattern 6 is formed on it, an insulating layer 7 is further provided, and a permalloy pattern. On this driving pattern, a hold magnetic layer 9 made of Ni-Co alloy is formed and an SiO2 protective film 10 is further provided to obtain a bubble memory chip. After an external magnetic field is applied in the optional horizontal direction of the chip to saturate the layer 9, the direction of the external magnetic field is inverted to apply a magnetic field H1, which is then cut off. Consequently, the layer 9 operates as a hold magnetic field. Then, the intensity of the external magnetic field is decreased to H2 to magnetize the layer 9, decreasing the hold magnetic field. |
