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This summary tabulates nuclear radiation effects data on large scale integrated (LSI) circuits. It is intended to be a handy reference to help engineers select components for systems that must survive a given radiation level or evaluate the radiation hardness of previously designed systems. Most of the data in this report were compiled from papers presented at the Annual IEEE Conference on Nuclear and Space Radiation Effects (1971 through 1979). The remainder came from a variety of government and industry reports. Due to the complexity of testing procedures of LSI devices and the space constraints of a tabular format, not all pertinent data can be presented in this summary. We have attempted to give most of the data needed for assessing the hardness of a given component. The balance of the information can be found in the references.

This patent describes an integrated optical signal communicating device associating an optical waveguide for guiding a light wave with a light-emitting junction for emitting the light wave and a light-collecting junction for receiving at least a part of the light wave. The device utilizes the gallium aluminum arsenide alloy system in the fabrication of the waveguide, emitter and collector to produce a device with high radiation resistance., Supersedes PAT-APPL-645 745-75.

The susceptibility to ionizing radiation of small sample lots of candidate hardened C-MOS devices was evaluated. All except an early pilot line device with an undoped SiO2 gate dielectric exhibited small total dose susceptibility out of 1,000,000 rads (Si). Other studies (e.g., annealing and high temperature performance) also are reported. A test plan for more extensive evaluation of larger lots is discussed. Future work will concentrate on instrumentation development to implement that test plan and evaluation of new samples according to the plan., Defense Nuclear Agency, Washington, D.C.

The effects of neutron and gamma irradiation on high-power (>200 mW) GaAs dome infrared emitters are reported. The threshold radiation levels for degradation of radiated power output, power efficiency, and external quantum efficiency are observed for neutron fluences of 1 x 10 to the 12th power n/sq. cm. (E > 10 keV) and for total gamma doses of 1 million rads (Si). These parameters decrease by three orders of magnitude at 2.2 x 10 to the 14th power n/sq. cm. for the neutron-irradiated device, and at 10 to the 8th power rads (Si) for the gamma-irradiated device. The reduction in power efficiency and external quantum efficiency with irradiation can be explained by the reduction in total minority carrier lifetime. The effect of radiation on the dome is negligible. The results of intensity-voltage and current-voltage measurements confirm that, even under the effects of nuclear irradiation, light is emitted in the diffusion region of the junction and that the charge flow is a diffusion process. (Author)

The paper reports the effects of gamma and neutron irradiation on the power output and efficiencies of a commercial, high-power GaAs LED of current interest to system designers.