Effect of top electrode material on radiation-induced degradation of ferroelectric thin film structures

Journal Article · Thu Jul 14 00:00:00 EDT 2016 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4955424· OSTI ID:22597857

Brewer, Steven J.; Bassiri-Gharb, Nazanin ^[1]; Deng, Carmen Z.; Callaway, Connor P. ^[2]; Paul, McKinley K. ^[1]; Fisher, Kenzie J. ^[1]; Guerrier, Jonathon E.; Jones, Jacob L. ^[3]; Rudy, Ryan Q.; Polcawich, Ronald G. ^[4]; Glaser, Evan R.; Cress, Cory D. ^[5]

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1. G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)
2. School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)
3. Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States)
4. Army Research Laboratory, Adelphi, Maryland 20783 (United States)
5. Naval Research Laboratory, Washington, DC 20375 (United States)

The effects of gamma irradiation on the dielectric and piezoelectric responses of Pb[Zr{sub 0.52}Ti{sub 0.48}]O{sub 3} (PZT) thin film stacks were investigated for structures with conductive oxide (IrO{sub 2}) and metallic (Pt) top electrodes. The samples showed, generally, degradation of various key dielectric, ferroelectric, and electromechanical responses when exposed to 2.5 Mrad (Si) {sup 60}Co gamma radiation. However, the low-field, relative dielectric permittivity, ε{sub r}, remained largely unaffected by irradiation in samples with both types of electrodes. Samples with Pt top electrodes showed substantial degradation of the remanent polarization and overall piezoelectric response, as well as pinching of the polarization hysteresis curves and creation of multiple peaks in the permittivity-electric field curves post irradiation. The samples with oxide electrodes, however, were largely impervious to the same radiation dose, with less than 5% change in any of the functional characteristics. The results suggest a radiation-induced change in the defect population or defect energy in PZT with metallic top electrodes, which substantially affects motion of internal interfaces such as domain walls. Additionally, the differences observed for stacks with different electrode materials implicate the ferroelectric–electrode interface as either the predominant source of radiation-induced effects (Pt electrodes) or the site of healing for radiation-induced defects (IrO{sub 2} electrodes).

• OSTI ID: 22597857
• Journal Information: Journal of Applied Physics, Vol. 120, Issue 2; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COBALT 60
ELECTRIC FIELDS
ELECTRODES
FERROELECTRIC MATERIALS
GAMMA RADIATION
HEALING
HYSTERESIS
INTERFACES
IRIDIUM OXIDES
IRRADIATION
OZONE
PERMITTIVITY
PLATINUM
POLARIZATION
PZT
STACKS
THIN FILMS