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Johnston, A. H.

Publications and source records attributed to Johnston, A. H..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2013

Charge Yield at Low Electric Fields: Considerations for Bipolar Integrated Circuits

A significant reduction in total dose damage is observed when bipolar integrated circuits are irradiated at low temperature. This can be partially explained by the Onsager theory of recombination, which predicts a strong temperature dependence for charge yield under low-field conditions. Reduced damage occurs for biased as well as unbiased devices because the weak fringing field in thick bipolar oxides only affects charge yield near the Si/SiO2 interface, a relatively small fraction of the total oxide thickness. Lowering the temperature of bipolar ICs - either continuously, or for time periods when they are exposed to high radiation levels - provides an additional degree of freedom to improve total dose performance of bipolar circuits, particularly in space applications.

ionizing radiation↗
NASA NTRS2012

Total Dose Effects on Bipolar Integrated Circuits at Low Temperature

Total dose damage in bipolar integrated circuits is investigated at low temperature, along with the temperature dependence of the electrical parameters of internal transistors. Bandgap narrowing causes the gain of npn transistors to decrease far more at low temperature compared to pnp transistors, due to the large difference in emitter doping concentration. When irradiations are done at temperatures of -140 deg C, no damage occurs until devices are warmed to temperatures above -50 deg C. After warm-up, subsequent cooling shows that damage is then present at low temperature. This can be explained by the very strong temperature dependence of dispersive transport in the continuous-time-random-walk model for hole transport. For linear integrated circuits, low temperature operation is affected by the strong temperature dependence of npn transistors along with the higher sensitivity of lateral and substrate pnp transistors to radiation damage.

linear integrated circuits↗
NASA NTRS2003

Displacement damage characterization of laser diodes

Displacement damage effects from protons and neutrons are compared. Differences in the annealing properties were observed which are due to the different microscopic structure of the damaged regions from the two ty pes of particles.

Miyahira, T. F.↗
NASA NTRS2003

Single-event upset in advanced commercial power PC microprocessors

Single-event upset from heavy ions in measured for advanced commercial microprocessors, comparing upset sensitivity in registers and d-cache for several generations of devices. Multiple-bit upsets and asymmetry in registers upset cross sections are also discussed.

single-event upset advanced commercial power PC pr↗
NASA NTRS2003

Single-event upset in evolving commercial silicon-on-insulator microprocessor technologies

Single-event upset effects from heavy ions are measured for Motorola and IBM silicon-on-insulator (SOI) microprocessors with different feature sizes and core voltages. Multiple-bit upsets (MBU) in registers and were measured and compared with single-bit upsets. Also, the scaling of the cross section with reduction of feature size for SOI microprocessors was discussed.

Yoder, G. I.↗
NASA NTRS2002

Latent damage in CMOS devices from single-event latchup

Latent damage effects from single-event latchup are studied, revealing a previously unconsidered reliability hazard for CMOS devices. Several device types were found to remain functional despite significant structural damage to their interconnects from SEL.

single-event↗
NASA NTRS2002

Single-event transients in high-speed comparators

Single-event transients are produced in linearintegrated circuits when they are exposed to heavy ions or protons, and those transients can be a significant problem for electronic circuits in spacecraft.

space↗
NASA NTRS2002

Low dose failures of hardened DC-DC power converters

Box-level total dose testing of the FOG (Fiber Optic Gyro) by IXSEA at ESA's GammabeamFacility were abruptly terminated at 8krad (Si) due to catastrophic failure (complete shutdown). This was unexpected because all components within the gyro were supposedly radiation tolerant. Further testing showed that the components responsible for the failure were two DC-DC converters, manufactured by Interpoint, that stopped regulating shortly before shutdown. This paper summarizes diagnostic test results for the converters to determine the underlying cause of the unexpected failure at low levels of radiation.

Interpoint Rad-hard DC-DC power converter TC4426 M↗