摘要
The effect of pyrolysis atmosphere is investigated for Bi3.25 La0.75 Ti3O12 （BLT） films prepared on Pt/TiO2/SiO2/p-Si（100substrates by sol-gel processes. The pyrolysis is carried out at 400℃ for 20 min under air or O2 atmosphere and the successive anneal is performed at 700℃ for 30min under O2 atmosphere. The pyrolysis under O2 is enough for complete removal of organic species, however after pyrolysis under air, carbon and hydrogen atomic species as organic fragment are partly remained in the film. This incomplete removal of organic fragments affects the grain growth and cause more defects in the film or between interfaces during the annealing for the crystallization of BLT film. The growth direction and grain size of the BLT film is revealed to affect ferroelectric properties. The remanent polarization PTfor the BLT films of pyrolysis in O2 and air are measured to be 18.85μC/cm^2 and 12.56μC/cm^2,respectively. The defects degrade the fatigue property dramatically for the film of pyrolysis in air. It can be concluded that the pyrolysis is an important procedure to control ferroeleetrie properties.
The effect of pyrolysis atmosphere is investigated for Bi3.25 La0.75 Ti3O12 （BLT） films prepared on Pt/TiO2/SiO2/p-Si（100substrates by sol-gel processes. The pyrolysis is carried out at 400℃ for 20 min under air or O2 atmosphere and the successive anneal is performed at 700℃ for 30min under O2 atmosphere. The pyrolysis under O2 is enough for complete removal of organic species, however after pyrolysis under air, carbon and hydrogen atomic species as organic fragment are partly remained in the film. This incomplete removal of organic fragments affects the grain growth and cause more defects in the film or between interfaces during the annealing for the crystallization of BLT film. The growth direction and grain size of the BLT film is revealed to affect ferroelectric properties. The remanent polarization PTfor the BLT films of pyrolysis in O2 and air are measured to be 18.85μC/cm^2 and 12.56μC/cm^2,respectively. The defects degrade the fatigue property dramatically for the film of pyrolysis in air. It can be concluded that the pyrolysis is an important procedure to control ferroeleetrie properties.
基金
Supported by Key Project of the National Natural Science Foundation of China under Grant No 90407023.
