Domain motions in epitaxial Pb(Zr,Ti)O3 thin film capacitors by piezoresponse scanning force microscopy

Domain motions in epitaxial Pb(Zr,Ti)O₃ thin film capacitors were investigated by piezoresponse scanning force microscopy (PFM) and switching current measurements. PFM observations revealed that switched domains increased from 8 to 92% of the scanning area as the switching pulse width increased from 80 to 200ns. Switching currents were successfully measured using a resistance load circuit built in the PFM system. Rapid drop at the trailing edge of switching current transients suggests that domain motions immediately froze at the removal of the external voltage when the switching pulse width was shorter than the switching time (∼250ns). Therefore, it can be considered that PFM images obtained after switching pulses with a shorter width than the switching time revealed transient domain structures during the polarization switching period. The shape index and switching time of the Ishibashi theory can be obtained as 3.6 and 165ns from PFM observations and 2.5 and 180ns from switching current measurements, respectively.