| 摘要 |
PURPOSE:To make possible reading of the direction of polarization of a ferroelectric body by distorting the ferroelectric body. CONSTITUTION:A ferroelectric thin film 2 is provided using p-type silicon on a single-crystal silicon substrate 1. On the ferroelectric thin film 2, input/output electrodes 3 and parallel electrodes 4 for driving surface acoustic waves are provided. Information is written by applying a voltage between the substrate 1 and the input/output electrodes 3 to polarize the ferroelectric thin film 2. Since upward or downward polarization is generated depending upon polarization of the applied voltage, information '1' or '0' corresponding to the direction of polarization is recorded. In reading information, a high frequency voltage is applied to the parallel electrodes to drive the surface acoustic waves. The difference in current between a signal side electrode and a reference electrode is employed as an output signal. If both electrodes have the ferroelectric thin films in the same direction, the output is zero. If the ferroelectric thin films are in the opposite directions, a large output signal is generated. Therefore, the direction of polarization recorded in ferroelectric thin film on the signal side may be read out. |
