Leakage Current and Dielectric Properties of Integrated Ferroelectric Capacitor Etched in Non-Crystalline Phase

Abstract

The leakage current, dielectric and loss properties of the integrated Pt/PbTiO3/ PbZr0.3Ti0.7O3/PbTiO3/Pt capacitors have been investigated. The capacitor has a same leakage mechanism as the film, in the low field region (less than 100 kV/cm) is Ohmic-like, and in the high field region (above 100 kV/cm) is Space-charge-limited current with deep traps. It also indicates that the process didn't affect the conduction mechanism in the capacitors, which is still determined by intrinsic character of materials. The dielectric constant of the capacitors is lower than that of the films. The loss of the capacitors is lower than thin film in the low frequency region (less than 500 kHz), and it is larger in the high frequency region (above 500 kHz). The DC voltage dependence of dielectric loss characteristic indicates that the possibility of main loss mechanism is the charge defects. The different properties between the integrated capacitors and films are ascribed to the excess Pb which volatilization is obstructed by the top electrode. The more excess Pb ion in the integrated capacitors act as charge defects, and the higher density of charged defects result in the different properties of the capacitor.