Influence of Film Texture on Reliability of Sol-gel Derived PZT Thin-film Capacitors

摘要

Time-dependent dielectric breakdown (TDDB) of lead titanate zirconate (PZT) thin-film capacitors derived by a sol-gel deposition process has been studied. Without any change in heat treatment conditions such as temperature, ramping rate, and keeping time, the film's grain size was varied by adding a small amount of organic additive to PZT sol-gel solution for a control of nucleation to form PZT oxide. The reliability was remarkably improved by fabricating interfaces with multi-annealing process, parallel to film surface when the grain size is greater than film thickness, which seems to suppress conductivity of oxygen vacancies.