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Performance and reliability of solid tantalum capacitors at cryogenic conditions
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Teverovsky, Alexander |
| Copyright Year | 2006 |
| Description | Performance of different types of solid tantalum capacitors was evaluated at room and low temperatures, down to 15 K. The effect of temperature on frequency dependencies of capacitance, effective series resistances (ESR), leakage currents, and breakdown voltages has been investigated and analyzed. To assess thermo-mechanical robustness of the parts, several groups of loose capacitors and those soldered on FR4 boards were subjected to multiple (up to 500) temperature cycles between room temperature and 77 K. Experiments and mathematical modeling have shown that degradation in tantalum capacitors at low temperatures is mostly due to increasing resistance of the manganese cathode layer, resulting in substantial decrease of the roll-off frequency. Absorption currents follow a power law, I approximately t(sup -m), with the exponent m varying from 0.8 to 1.1. These currents do not change significantly at cryogenic conditions and the value of the exponent remains the same down to 15 K. Variations of leakage currents with voltage can be described by Pool-Frenkel and Schottky mechanisms of conductivity, with the Schottky mechanism prevailing at cryogenic conditions. Breakdown voltages of tantalum capacitors increase and the probability of scintillations decreases at cryogenic temperatures. However, breakdown voltages measured during surge current testing decrease at liquid nitrogen (LN) compared to room-temperature conditions. Results of temperature cycling suggest that tantalum capacitors are capable of withstanding multiple exposures to cryogenic conditions, but the probability of failures varies for different part types. |
| File Size | 7034208 |
| Page Count | 9 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20060026218 |
| Archival Resource Key | ark:/13960/t9x112r02 |
| Language | English |
| Publisher Date | 2006-01-01 |
| Access Restriction | Open |
| Subject Keyword | Metals And Metallic Materials Leakage Electric Potential Capacitors Probability Theory Cryogenic Temperature Tantalum Temperature Effects Capacitance Solids Reliability Soldering Room Temperature Cathodes Manganese Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
