Pulsed Laser Deposition of SrBi 2 Ta 2 O 9 Thin Films on Si Substrate

Systematic study of pulsed laser deposition of non‐ c ‐axis‐oriented polycrystalline SrBi 2 Ta 2 O 9 ferroelectric thin films on Pt‐coated silicon substrates has been performed. Both in situ and ex situ routes have been explored. Ex situ deposited films produced predominantly (115) and (200) orientations, while in situ deposition resulted in a mixture of (115) and (104) orientations. The growth was studied as a function of the ceramic targets Bi‐enrichment, target‐substrate distance, annealing temperature, and the utilization of an external electric field applied on the substrate during the post‐annealing procedure. Variation of those parameters appears to significantly affect the phase purity and crystalline quality of the films. The minimization of pyrochlore and fluorite phases and the related Bi 2 Pt formation have been achieved through the introduction of layered Bi‐enrichment gradient architecture and lowering the annealing temperature. SBT d 33 piezoelectric coefficients of an order of 12–15 were measured. X‐ray diffraction was used to characterize structural perfection of the films. The nanoscale mechanism of piezoelectric behavior has been investigated by means of piezoresponse force microscopy. Electromechanical hysteresis loops of SBT films. image Electromechanical hysteresis loops of SBT films.