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MRED is a Python-language scriptable computer application that simulates radiation transport. It is the computational engine for the on-line tool CRÈME-MC. MRED is based on c++ code from Geant4 with additional Fortran components to simulate electron transport and nuclear reactions with high precision. We provide a detailed description of the structure of MRED and the implementation of the simulation of physical processes used to simulate radiation effects in electronic devices and circuits. Extensive discussion and references are provided that illustrate the validation of models used to implement specific simulations of relevant physical processes. Several applications of MRED are summarized that demonstrate its ability to predict and describe basic physical phenomena associated with irradiation of electronic circuits and devices. These include effects from single particle radiation (including both direct ionization and indirect ionization effects), dose enhancement effects, and displacement damage effects. MRED simulations have also helped to identify new single event upset mechanisms not previously observed by experiment, but since confirmed, including upsets due to muons and energetic electrons. [ABSTRACT FROM AUTHOR]

SEU enhancements were introduced into a radiation hardened 90 nm CMOS technology to achieve upset immunity. An incremental enhancement approach that enables various SEU/performance trade-off was demonstrated on the same basic SRAM cell to achieve various degrees of hardness, by the selective utilization of enhancement features. Single event upset testing, as well as MRED simulation, have demonstrated a significant enhancements achieved with a minimal performance penalty. [ABSTRACT FROM AUTHOR]

Heavy-ion measurements on 40-nm flip-flops indicate pattern dependence of cross-section resulting from local control logic upsets, such as clock nodes. A Monte-Carlo model of the flip-flop, calibrated to the heavy-ion data, is used to analyze the impact of multi-node charge collection within a flip-flop due to a single particle strike. Depending on the nodes that collect charge, multi-node charge collection can either increase or decrease the vulnerability of the cell. For neutrons, the overall effect of such events was found to be a net increase in cross-section by up to 16%. [ABSTRACT FROM AUTHOR]

Monte-Carlo simulation using the MRED software suite, coupled with SPICE analysis, is used to identify internal mechanisms of SEU in DICE flip-flops. Low frequency cross-section measurements and simulations identify multiple-node charge collection SEU mechanisms as the dominant contributor. An increasingly isotropic response is predicted with increasing frequency due to latching of internal single-node transients near clock boundaries. Implications for heavy ion testing and SEU rate prediction are presented. [ABSTRACT FROM AUTHOR]

Monte-Carlo radiation transport code is coupled with SPICE circuit level simulation to identify regions of single event upset vulnerability in an SEU hardened flip-flop, as well as predict single event upset cross sections and on-orbit soft error rates under static and dynamic operating conditions. [ABSTRACT FROM PUBLISHER]

Heavy ion cross section data taken from a hardened-by-design circuit are presented which deviate from the traditional single sensitive volume or classical rectangular parallelepiped model of single event upset. TCAD and SPICE analysis demonstrate a SEU mechanism dominated by multiple node charge collection. Monte Carlo simulation is used to model the response and predict an on-orbit error rate. [ABSTRACT FROM AUTHOR]

Heavy ion irradiation was simulated using a Geant4 based Monte-Carlo transport code. Electronic and nuclear physics were used to generate statistical profiles of charge deposition in the sensitive volume of an SEU hardened SRAM. Simulation results show that materials external to the sensitive volume can affect the experimentally measured cross-section curve. [ABSTRACT FROM AUTHOR]

Simulations show that neglecting ion-ion interaction processes (both particles having Z > 1) results in an underestimation of the total on-orbit single event upset error rate by more than two orders of magnitude for certain technologies. The inclusion of ion-ion nuclear reactions leads to dramatically different SEU error rates for CMOS devices containing high Z materials compared with direct ionization by the primary ion alone. Device geometry and material composition have a dramatic effect on charge deposition in small sensitive volumes for the spectrum of ion energies found in space, compared with the limited range of energies typical of ground tests. [ABSTRACT FROM AUTHOR]