Preparation And Study On Ferroelec- Tric Propertiy Of Lead Zirconate Ti-Tanate Nanoparticlples Based On AAO Template Method

Lead zirconate titanate Pb(Zr,Ti)O3(PZT),as a ferroelectric storage material,has attracted many scholars to study it for its excellent ferroelectric properties.With the amount of information increasing,a new type of memory with high density and low power consumption is in urgent needed.Compared with the traditional flash memory,the ferroelectric memory fabricated by PZT nano material has the advantages of low power consumption and nonvolatile,but there are still some disadvantages of low storage density at present.Moreover,the properties of ferroelectric nanostructures are greatly influenced by their morphology.How to ensure the same shape and size of ferroelectric nanostructures has became the focus of current research on ferroelectric nanomaterials.Based on this,this article used two step anodization method to make ultra-thin AAO film,then PZT nanodots is prepared by using the pulsed laser deposition technique(PLD).Finally test the piezoelectric and ferroelectric properties using piezoelectric microscope.And establish the experimental foundation for the subsequent application.This article used the two steps anodic oxidation method to prepare AAO film.The electrolyte is 0.3 mol/L oxalic acid,the oxidation voltage is 40 V,the oxidation temperature is 0-5 °C,the first oxidation time is 2 h,and the second oxidation time is 5 min.Finally removing of aluminum matrix and the barrier layer.We have successfully prepared ultra-thin AAO film,the pore size is 50 nm,70 nm,90 nm and 100 nm,and the reaming rate is 0.633 nm/min by calculation.At the same time,It is found that high annealing temperature and electrochemical polishing have great influence on the formation quality of AAO film.After annealing at 500 °C,the internal stress of aluminum foil can be eliminated and the grain size can be increased.The micro burr on the surface of aluminum foil can be removed and the surface smoothness can be improved by electrochemical polishing of aluminum foil.PZT nanodots were prepared on different substrates by pulsed laser deposition(PLD)technique.Platinum silicon was used as the substrate,The deposition temperature/annealing temperature is 500 °C/700 °C(30 min)and 550 °C/750 °C(30 min),Regular ordered PZT nanodots were prepared,and the phase matching is better at the deposition temperature / annealing temperature of 500 °C /700 °C(30 min).Then the niobium doped strontium titanate(Nb-STO)substrate is used in the deposition temperature/annealing temperature of 450 °C/650 °C(30 min),the oxygen pressure is 5 Pa and 10 Pa,the annealing oxygen pressure is 8000 Pa.The regular PZT nanodots were prepared,and the phase matching ratio is better than that of platinum silicon substrate.The properties of PZT nanodots was measured by PFM.On the substrate of Nb-STO,the deposition temperature/annealing temperature is 450 °C /650 °C(30 min),the oxygen pressure is 5 Pa,the pulse frequency is 10 Hz,the laser energy is 300 m J,and the pulse laser number is 1500 times.The ferroelectric properties are optimal,and polarization reversal angle can reach about 175 degrees.The maximum piezoelectric constant d33 of PZT nanodots is 58 pm/V,while the piezoelectric constant d33 of PZT film prepared under the same conditions is 37 pm/V.It is proved that the piezoelectric and ferroelectric properties of the PZT nanodots are superior to those of PZT film.