Reliability of Sol-Gel Derived Ferroelectric Memories
Abstract
A process was developed to prepare PZT(52/48) precursor solutions. Five spin-on depositions of this solution (0.5M) were necessary to grow 0.5 micron thin films of polycrystalline PZT onto PT passivated silicon wafers. An addition of 15% excess Pb0 aided the densification process. Films derived from l.5M solutions resulted in PZT films of equivalent thickness in only two depositions. Dielectric constant and tan Sigma were 800 and 2% respectively, at 1 kHz. Remnant and saturation polarizations were 12 and 25 micron C/cm2, respectively. Coercive fields of 36-48 kv/cm were measured. From retention experiments, a polarization loss of 11.2% after 3.2 years was estimated (i.e., the switched charge would diminish from 5.8 to 5.2 AC/CM2). High frequency pulse fatigue data on Nb and Sn modified PZT showed a reduction of the switched charge of 26% after 4x,10 12 polarization reversals.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1992
- Accession Number
- ADA255240
Entities
People
- Sandwip K. Dey
Organizations
- Arizona State University