abstract
Bismuth zinc niobate (Bi2Zn2/Nb-3(4)/O-3(7)) thin films were deposited by PLD on fused silica substrates at different oxygen pressures. The structural, microwave dielectric, optical and Raman characteristics of these thin films were systematically studied for both the as-deposited films and films annealed at 600 degrees C. The microwave dielectric constant at a frequency of 10 GHz of the annealed m-BZN films varied from 56 to 71, whereas the dielectric loss tangent varied from 1.8 x 10(-4) to 3.5 x 10(-4) as a function of deposition pressure. The as-deposited films exhibit refractive index in the range of 2.06-2.15 with an optical absorption edge value between 3.59 and 3.67 eV. The observed Raman scattering in m-BZN thin films was slightly shifted toward the higher frequency which reveals that the local lattice disorder changes whereas the structure remains the same monoclinic in thin film as well as in bulk.
keywords
DIELECTRIC-PROPERTIES; PYROCHLORE; BISMUTH; TEMPERATURE; ABSORPTION
subject category
Physics
authors
Sudheendran, K; Singh, MK; Krishna, MG; Raju, JKC
our authors
Sudheendran Kooriyattil
Post-doc FellowshipGroups
acknowledgements
The authors acknowledge UGC and DST for the financial support for this work. We also acknowledge Dr. Sudipta Roy Barman and CSR, Indore Centre for extending the XPS facility and Prof. Ram S. Katiyar, University of Puerto Rico, for the Raman facility. K. S. acknowledges FCT Portugal (SFRH/BPD/66918/2009) and CSIR India (DSRF09/414 (0768)/2008-EMR-I) for the support.