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.

Energetic neutrons with an atmospheric neutron spectrum, which were demonstrated to induce single event burnout in power MOSFETs, have been Shown to induce burnout in high voltage (>3000V) electronics when operated at voltages as low as 50% of rated voltage. The laboratory failure rates correlate well with field failure rates measured in Europe.

Single event burnout was seen in power MOSFETs exposed to high energy neutrons. Devices with rated voltage greater than or equal to 400 volts exhibited burnout at substantially less than the rated voltage. Tests with high energy protons gave similar results. Burnout was also seen in limited tests with lower energy protons and neutrons. Correlations with heavy-ion data are discussed. Accelerator proton data gave favorable comparisons with burnout rates measured on the APEX spacecraft. Implications for burnout at lower altitudes are also discussed.

A variety of charge collection measurements by energetic protons and neutrons have been measured and compared. These include deposition in: small silicon junctions, large volume American and Russian silicon surface barrier detectors, and InGaAs photodiodes.

A new solar flare heavy ion model has been developed to support Space Station Single Event Effects (SEE) evaluations. It shows good agreement with previous flare data, and is implemented through an improved version of the CREME code.

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.

RAMs, microcontrollers and surface barrier detectors were exposed to beams of high energy protons and neutrons to measure the induced number of upsets as well as energy deposition. The WNR facility at Los Alamos provided a neutron spectrum similar to that of the atmospheric neutrons. Its effect on devices was compared to that of protons with energies of 200, 400, 500 and 800 MeV. Measurements indicate that SEU cross sections for 400 MeV protons are similar to those induced by the atmospheric neutron spectrum.