Seeding effect of SrBi2Ta2xO9 thin buffer layer on crystallization and electric properties of SrBi2Ta2O9 thin films

The seeding effects of the pre-crystallized (RTP 750degC 30 s) thin buffer layer, SrBi
₂
Ta
_2x
O
₉
(SBT, x=0.9, 1.0, and 1.1), regarding the structure, the morphology and the ferroelectric properties of the SrBi
₂
Ta
₂
O
₉
ferroelectric thin films on top of buffer layer, have been investigated. X-ray diffraction patterns revealed that the crystallinity of SrBi
₂
Ta
₂
O
₉
thin films were significant influenced by the buffer layers with various Ta contents. By adding a Ta deficient buffer layer, the preferred polar alpha-axis orientation and the uniformity of grain size within the SBT thin films were promoted. Meanwhile, the optimized ferroelectric properties were achieved from the SrBi
₂
Ta
_1.8
O
₉
buffered SrBi
₂
Ta
₂
O
₉
thin film, with maximum 2Pr values about 19.7 mu C/cm
²
, which was almost 93% greater than that of specimen with the stoichiometric buffered one.