Effects of Ionizing Radiation on Tantalum Capacitors
GULF RADIATION TECHNOLOGY SAN DIEGO CA
Pagination or Media Count:
Maverick radiation response in capacitors is caused by charge injection and storage within the oxide. While there are always sufficient traps to store charge in the oxide, for most capacitors significant injection of charge does not occur at the electrodes when bias of the correct polarity is applied. In a few capacitors, one or both electrodes do not block adequately and charge can be injected and trapped in the Ta2O5. Ionizing radiation releases this trapped charge, and the charge can then move under the influence of the built-in bias plus the space-charge field, producing an anomalously large zero- bias radiation transient. Capacitors which can readily store charge can be eliminated from the population by application of the appropriate electrical screen. Once a population has been screened, indications are that the introduction rate of maverick capacitors under normal use conditions, including a screening dose of radiation, is about the same as the failure rate due to aging.
- Electrical and Electronic Equipment
- Radioactivity, Radioactive Wastes and Fission Products