Accession Number : ADA255358


Title :   Reliability of Sol-Gel Derived Ferroelectric Memories


Descriptive Note : Final progress rept. 1 Jul 89-30 Jun 92,


Corporate Author : ARIZONA STATE UNIV TEMPE


Personal Author(s) : Dey, Sandwip K


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a255358.pdf


Report Date : Jul 1992


Pagination or Media Count : 8


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 PbO aided the densification process. Films derived from 1.5M 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/sq cm, 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 micron C/sq cm). High frequency pulse fatigue data on Nb and Sn modified PZT showed a reduction of the switched charge of 26% after 4x10(exp 12) polarization reversals.


Descriptors :   *THIN FILMS , *FERROELECTRIC MATERIALS , FREQUENCY , THICKNESS , POLARIZATION , DIELECTRICS , SATURATION , DEPOSITION , SILICON , FATIGUE , POLYCRYSTALLINE , GELS , WAFERS , CONSTANTS , PULSES , REDUCTION , FILMS , HIGH FREQUENCY , PRECURSORS , PROCESSING


Subject Categories : Electricity and Magnetism


Distribution Statement : APPROVED FOR PUBLIC RELEASE