Direct Observation of Capacitor Switching Using Planar Electrodes

作者：Balke Nina^*; Gajek Martin; Tagantsev Alexander K; Martin Lane W; Chu Ying Hao; Ramesh Ramamoorthy; Kalinin Sergei V

来源：Advanced Functional Materials, 2010, 20(20): 3466-3475.

DOI：10.1002/adfm.201000475

Ferroelectric polarization switching in epitaxial (110) BiFeO3 films is studied using piezoresponse force microscopy of a model in-plane capacitor structure. The electrode orientation is chosen such that only two active domain variants exist. Studies of the kinetics of domain evolution allows clear visualization of nucleation sites, as well as forward and lateral growth stages of domain formation. It is found that the location of the reverse-domain nucleation is correlated with the direction of switching in a way that the polarization in the domains nucleated at an electrode is always directed away from it. The role of interface charge injection and surface screening charge on switching mechanisms is explored, and the nucleation is shown to be controllable by the bias history of the sample. Finally, the manipulation of domain nucleation through domain structure engineering is illustrated. These studies pave the way for the engineering and design of the ferroelectric device structures through control of individual steps of the switching process.

• 出版日期2010-10-22