TY - JOUR
KW - Thin films
KW - Electric potential
KW - Crystal orientation
KW - Electrodes
KW - Ferroelectric materials
KW - Capacitors
KW - Grain boundaries
KW - X-ray diffraction analysis
KW - Metallorganic chemical vapor deposition
KW - Crystallographic orientations
KW - Ferroelectric random access memory (FRAM)
KW - Nanoscale polarization relaxation
KW - Piezoresponse force microscopy (PFM) images
KW - Correlation methods
KW - Polycrystalline materials
AU - V Nagarajan
AU - S Aggarwal
AU - A Gruverman
AU - Ramamoorthy Ramesh
AU - R Waser
AB - In this letter, we report on the study of nanoscale polarization relaxation phenomena in polycrystalline PbZr0.4 Ti0.6 O3 films. Piezoresponse force microscopy (PFM) images of the as-grown sample reveal grains with a range of contrast, from fully white to gray to fully black. It is shown that this local change in the contrast (magnitude) of the piezoresponse from grain to grain can be attributed to the crystallographic orientation within each grain. PFM-based relaxation experiments show that the rate of relaxation is different for each grain, furthermore it is strongly dependent on the tilt of individual crystallographic orientation with respect to the polar axis. Strongly tilted away nonpolar axis grains show a much stronger decay of the polarization compared to polar axis-oriented grains. Therefore, for an ensemble of grains under a common top electrode, the relaxation events would first take place in grains, which are nonpolar axis oriented. © 2005 American Institute of Physics.
BT - Applied Physics Letters
DO - 10.1063/1.1977183
LA - eng
M1 - 26
N1 - cited By 33
N2 - In this letter, we report on the study of nanoscale polarization relaxation phenomena in polycrystalline PbZr0.4 Ti0.6 O3 films. Piezoresponse force microscopy (PFM) images of the as-grown sample reveal grains with a range of contrast, from fully white to gray to fully black. It is shown that this local change in the contrast (magnitude) of the piezoresponse from grain to grain can be attributed to the crystallographic orientation within each grain. PFM-based relaxation experiments show that the rate of relaxation is different for each grain, furthermore it is strongly dependent on the tilt of individual crystallographic orientation with respect to the polar axis. Strongly tilted away nonpolar axis grains show a much stronger decay of the polarization compared to polar axis-oriented grains. Therefore, for an ensemble of grains under a common top electrode, the relaxation events would first take place in grains, which are nonpolar axis oriented. © 2005 American Institute of Physics.
PY - 2005
SP - 1
EP - 3
T2 - Applied Physics Letters
TI - Nanoscale polarization relaxation in a polycrystalline ferroelectric thin film: Role of local environments
VL - 86
SN - 00036951
ER -