New silicon-based ferroelectric sandwich structure

摘要

A new silicon-based PbTiO/sub 3//Pb(Zr,Ti)O/sub 3//PbTiO/sub 3/ (PT/PZT/PT) sandwich structure is prepared using a sol-gel method. The annealing temperature is greatly reduced compared with that without PT layers. Capacitance-voltage (C-V), current density - electric field (J-E), polarization-field (P-E) and dielectric-frequency responses of the sandwich structure are studied. The maximum dielectric constant of about 900 is obtained at the coercive field 18 kV/cm, and the remnant polarization is 16 /spl mu/C/cm/sup 2/. The current density is 5 /spl times/ 10/sup -9/ A/cm/sup 2/ below 200 KV/cm. The dielectric constant of the structure stays constant at low frequency, and decreases to some degree at high frequency. The PZT films are proved to have very good dielectric and ferroelectric properties. The PT/PZT/PT sandwich structure will have a use in memory devices and other applications.