FERROELECTRIC MEMORY

• Main Authors: TANAKA HITOSHI, KIMURA KATSUTAKA, SAKATA TAKESHI, TORII KAZUNARI, ISODA MASANORI
• Format: Patent
• Language: English
• Published: 19.09.1997
• Edition: 6
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; INFORMATION STORAGE; PHYSICS; SEMICONDUCTOR DEVICES; STATIC STORES

PROBLEM TO BE SOLVED: To return an electric field applied to a ferroelectric capacitor to zero accurately to initialize characteristics by a pulse that is not prescribed by conditions such as temperature and stress in a ferrodielectric memory. SOLUTION: In the initialization, switches Sot and Sob are opened and switches Sdt and/or Sdb are closed to connect an attenuation vibration circuit DP to an IO wire. Ferrodielectric capacitors CO-Cn are selected by a line selection signal YSn and required word lines WO-Wn to apply an output Dpo of the attenuation vibration circuit. A potential of a plate line PL is shifted to an intermediate potential of the output Dpo by a plate voltage source VR. The voltage amplitude of the output pulse Dpo is gradually attenuated to turn an electric field applied to the capacitor to zero finally. In the normal operation, the switches Sot and Sob are closed and the switches Sdt and Sdb are opened. Thus, improved degrading in characteristic of the ferrodielectric allows reduction in malfunctioning of the ferroelectric memory thereby enhancing the reliability of a system.