Defect Characterization of Oxide Materials for Pyroelectric Detector Applications
Abstract
Characterisation of atomic-scale defects in oxides with application to pyroelectric detectors has been performed. The materials studied were ferroelectric PbTiO3, (Pb,La)TiO3, and (Pb,La)(Zr,Ti)O3 and the conducting oxide La(x)Sr(1-x)CoO3. Thin films have been studied using the vacancy-related defect sensitive technique positron annihilation. Variable energy positron beam (VEPB) measurements on Pb(1-y)La(y)Zr(0.2)Ti(0.8)O3 (PLZT) for y = 0.005, 0.03, 0.06 and 0.10 were performed. The variation in annihilation characteristics was compared to the results expected from defect chemistry. The first coincidence-detection VEPB measurements on PLZT films were made. Measurements on PLZT thin films, x = 0.0 and x = 0.10, processed to give different oxygen deficiencies were made and correlated with structural measurements on the films. PLZT capacitor structures with LaSrCoO3 electrodes processed in oxygen deficient ambients were then studied. Again, correlation with electrical and structural characterization measurements was made. Electron paramagnetic resonance has been used to study PbTiO3. Temperature dependence of the spectrum from Mn(4+) allowed local structure information to be inferred. Preliminary measurements on thin film PLZT layers were attempted. This formed a complementary part of the ARL program on ferroelectric materials and infrared detectors and involved collaboration with ARL and with MRCP/MICRA programs at Univ. Maryland and Brookhaven.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 22, 1999
- Accession Number
- ADA378519
Entities
People
- D. J. Keeble
Organizations
- University of Dundee