In this paper we review cosmic ray effects on the performance and reliability of microelectronic systems and human health as well as the development of the engineering and health science tools used to evaluate and mitigate cosmic ray effects in ground-based, atmospheric flight, and space flight environments. Ground based test methods applied to microelectronic components and systems are used in combination with radiation transport and reaction codes to predict the performance of microelectronic systems in their operating environments. Similar radiation transport codes are an important tool for evaluating possible human health effects of cosmic ray. Finally, the limitations on human space operations beyond low-Earth orbit imposed by long term exposure to galactic cosmic rays are discussed.

The Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) is the next generation (RTG) being developed by DOE to provide reliable, long-life electric power for NASA's planetary exploration programs. The MMRTG is being developed by Pratt & Whitney Rocketdyne and Teledyne Energy Systems Incorporated (TESI) for use on currently planned and projected flyby, orbital and planet landing missions. This is a significant departure from the design philosophy of the past which was to match specific mission requirements to RTG design capabilities. Undefined mission requirements provide a challenge to system designers by forcing them to put a design envelope around "all possible missions". These multi-mission requirements include internal and external radiation sources. Internal sources include the particles ejected by decaying Pu-238 and its daughters plus particles resulting from the interaction of these particles with other MMRTG materials. External sources include the full spectrum of charged particle radiation surrounding planets with magnetic fields and the surfaces of extraterrestrial objects not shielded by magnetic fields. The paper presents the results of investigations into the environments outlined above and the impact of radiation exposure on potential materials to be used on MMRTG and ground support personnel. Mission requirements were also reviewed to evaluate total integrated dose and to project potential shielding requirements for materials. Much of the information on mission shielding requirements was provided by NASA's Jet Propulsion Laboratory. The primary result is an ionizing radiation design curve which indicates the limits to which a particular mission can take the MMRTG in terms of ionizing radiation exposure. Estimates of personnel radiation exposure during ground handling are also provided.

Technology advances in wafer processing and design, new device requirements and improved modeling necessitate the need for a careful determination of LET at and through the critical silicon region of interest during SEE testing.

Single event effects in electronics caused by the atmospheric neutrons have been an issue for systems using large blocks of random access memory (RAM) in avionics applications as well as those on the ground. At ground level there are two main sources of single event effects, alpha particles from the packaging materials as well as the neutrons, but at aircraft altitudes, where the neutron flux is about 300 times higher than the ground, the alpha particles make a negligible contribution. We review the trends over the last 5-10 years in the response of COTS computer systems to single event effects, taking into the response of devices as well as fault tolerant measures incorporated into the systems.

This compendium of SEGR and SEB data organizes results from several laboratories comparing failure thresholds for several different manufacturers and technologies. The results of this compendium are aimed at the designer to show the possible variations between manufacturers and processes. The compendium incorporates previously published data with the most recent data obtained from various sources.

High-voltage diodes with active areas between 1 cm(2) and 32 cm(2) were irradiated either with carbon ions having energies between 17 MeV and 252 MeV or ex-particles of 98 MeV or neutrons with energies up to 800 MeV. As the voltage across the devices was raised all of them failed eventually, even if there was a 1MOhm resistor in series. With the high-ernergy carbon ions it could be shown that the failure can be triggered at locations that are hundreds of microns away from the pn-junction. The neutron experiment indicates that there may be a steep fall-off in failure rate at the lowest voltages.

Microelectronic devices used in avionics were tested in the WNR beam, simulating atmospheric neutrons. The SEU upset rates for ARINC 429 receivers agree with rates in memories, and neutron-induced latchup was measured in the LCA100 K and 200 K gate arrays and compared against a new neutron-induced latchup model.