Ferroelectric Materials
AimsBefore you startIntroductionThe dipole momentPolarisationSwitching polarisation (1)Switching polarisation (2)Measurement of polarisationFabrication of a KNO3 ferroelectric capacitorTemperature dependence of the Hysteresis loopBarium titanateBarium titanate and phase changesOrder of phase transitionsFerroelectrics - why?SummaryQuestionsGoing furtherTLP creditsTLP contentsShow all contentViewing and downloading resourcesAbout the TLPsTerms of useFeedbackCredits Print this page
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Ferroelectrics - why?
Ferroelectric materials are used for binary information storage in FeRAM (Ferroelectric Random Access Memory). The zeroes and ones in each ferroelectric capacitor correspond to a polarization that is up or down. The polarization state is set up or down by applying a positive or negative voltage, and the polarization stays up or down after removing this voltage. FeRAM therefore offers non-volatile data storage. However, to read FeRAM data, the polarization must be electrically cycled, which takes time and erases the data (destructive read).
FeRAM was used in the Sony Playstation 2, and it has also been used in smart cards for Japanese railways.