Mechanical stress effect on imprint behavior of integrated ferroelectric capacitors
Stress-induced changes in the imprint and switching behavior of (111)-oriented Pb(Zr,Ti)O-3 (PZT)-based capacitors have been studied using piezoresponse force microscopy. Visualization of polarization distribution and d(33)-loop measurements in individual 1x1.5-mum(2) capacitors before and after stress application, generated by substrate bending, provided direct experimental evidence of stress-induced switching. Mechanical stress caused elastic switching in capacitors with the direction of the resulting polarization determined by the sign of the applied stress. In addition, stress application turned capacitors into a heavily imprinted state characterized by strongly shifted hysteresis loops and almost complete backswitching after application of the poling voltage. It is suggested that substrate bending generated a strain gradient in the PZT layer, which produced asymmetric lattice distortion with preferential polarization direction and triggered polarization switching due to the flexoelectric effect. (C) 2003 American Institute of Physics.
Gruverman, A N Carolina State Univ, Raleigh, NC 27695 USA N Carolina State Univ, Raleigh, NC 27695 USA Ecole Polytech Fed Lausanne, Ceram Lab, CH-1015 Lausanne, Switzerland Fujitsu Labs Ltd, Atsugi, Kanagawa 2430197, Japan
Cited References Count:23
Record created on 2006-08-21, modified on 2016-08-08