| 摘要 |
PURPOSE:To make it excellent in memory preserving property and prevent the deterioration of stored information by providing upper electrodes, where the first electrode, to which the voltage to generate a domain wall is applied, the second electrode, which suppresses the shifting of the domain wall, and the third electrode, to which the voltage to surround this domain wall is applied, are made in succession, and writing in and reading out information by the shifting of the domain wall. CONSTITUTION:When voltages VS, VT, and VD are applied to upper electrodes 17-19, the regions 21-23 corresponding to the upper electrodes 17-19 are polarized, and simple domain polarizations 26-28 are made. The writing operation is equivalent to applying voltage VD between the electrode 19 and the common lower electrode 20. When the voltage value is reset to VT>0, VD1>0 (but, VD>VD1>0), the condition 26 of the polarization of the region 21 is inverted as if the domain wall 30 has shifted to the domain wall 31, and causes 180 deg. inversion of polarization, and becomes reverse polarization. Hereby, it becomes excellent in memory preserving property and the deterioration of stored information becomes little. |
