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This paper presents a new methodology based upon backside laser irradiations to characterize the sensitivity of power devices towards Single-Event Burnout. It is shown that this technique can be used to define the safe operating area. Index Terms--Breakdown voltage, Burnout, laser, MOSFET, Single-Event Burnout (SEB).

This paper investigates the single event upset sensitivity of Bulk SRAMs for terrestrial applications. The technology sensitivity is analyzed with both quasi-monoenergetic neutron and proton experiments in an energy range from 14 to 180 MeV. Analytical and simulation based correction methods of the neutron cross section are presented and validated. Then, neutron and proton cross section are compared. Soft Error Rate (for the terrestrial neutron spectrum) calculated with either proton or quasi-monoenergetic neutron data are also presented and compared. Index Terms--Bulk technologies, neutron and proton effects, soft error rate (SER), single-event upset (SEU).

The charge sharing quantification in the case of neutron induced SEUs in a 130 nm bulk SRAM is presented. Conclusions on its contribution to the soft errors sensitivity evaluation using Monte-Carlo codes are underlined. Index Terms--Bulk, charge sharing, diffusion, neutron, SEU, SRAM, TCAD simulations.

This paper presents the new detailed analysis of the secondary ion effect analytical version that allows fast and accurate calculation of neutron, proton and heavy ion cross sections in SRAM based memories. The advantage of this new version is a better determination of the input parameters using heavy ion data. A validation is presented by comparing simulation results with experimental data for technology from 600 to 180-nm. Index Terms--Cross section prediction, SEU, SRAM.

This paper presents a new way of investigation using the laser method. It is based on laser threshold mappings of electronic devices. The main idea is to use these mappings in order to extract physical parameters, for instance sizes and shapes of the different sensitive areas of a component. These parameters can be used as input parameters for analytical or Monte Carlo calculation codes in order to predict the behavior of sensitive components towards radiations. Index Terms--Calculation codes, laser mappings, SEU, SRAM.

This paper investigates the sensitivity of SOI and Bulk SRAMs to neutron irradiations with energies from 14 to 500 MeV. The technology sensitivity is analyzed with both experiments and Monte Carlo simulations. In particular, simulations include the nuclear interactions of neutrons with both silicon and oxygen nuclei In-St and n-O), in order to investigate the influence of isolation upper layers on the device sensitivity. The device cross-sections are analyzed for mono-energetic neutron irradiations and discussed in terms of nuclear interaction type (n-St and n-O) and distribution of the secondary ion recoils. We also investigate the dimensions of the interaction volume around the sensitive cell as a function of the device architecture. Index Terms--Bulk technologies, SOI technologies, neutron effects, soft error rate (SER), single-event upset (SEU), Monte Carlo methods.

This paper presents a new 3D methodology to simulate Multiple Bit Upsets in commercial SRAMs. Experiments are performed at the Los Alamos neutron facility on 90, 130, and 250 nm SRAMs and compared to Monte-Carlo simulations. A discussion on ions inducing MBUs is also proposed. Index Terms--Bulk, diffusion, Monte-Carlo, multiple bit upsets (MBU), neutron, SEU, SRAM.

A reliable criterion for SEU occurrence simulation is presented. It expresses the relationship existing at threshold between the magnitude and duration of the ion-induced parasitic pulse. This criterion can be obtained by both three-dimensional device and SPICE simulations. Using this criterion, the simulated and experimental SER on 130 and 250 nm technologies are shown to be in good agreement.

This paper investigates the sensitivity of bulk technologies in the terrestrial neutron environment as a function of technology scaling. Their sensitivity is analyzed with both experiments and Monte Carlo simulations. The soft error rate (SER) of future technology generations is extrapolated, analyzed and discussed on the basis of different parameters such as the interaction volume, the secondary ion species and the incident neutron energy ranges. Index Terms--Bulk technologies, Monte Carlo methods, neutron effects, soft error rate, single-event upset, SRAM chips.

In this paper, we have pioneered a new direction concerning the shielding of electronic devices (at a micro-circuit-packaging or a larger level) in a radiative environment. As a matter of fact, this work not only considers the role of the material itself on the shielding efficiency but also the effect of the structure of the shield. By simulations with the NOVICE Code, we have explored the possibility of combining the specific attenuation properties of given materials in an optimized multilayer (and multimaterial) structure. This study is based on a brief theoretical overview of interaction of space radiation with material. Then, the results of simulations are presented. The workframe of these calculations is a worst-case geosynchronous orbit (160 [degrees] West) for a period of 15 years (trapped electrons and protons from 4 anomalously large solar particle events). We found that it is possible to improve the shielding properties of a monomaterial absorber by using an optimized multilayer, multimaterial shield.

The ARIANE 5 On Board Computer (OBC) and Inertial Reference System (SRI) are based on MOTOROLA MC68020 processor and MC68882 coprocessor. The SRI data acquisition board also uses the DSP TMS320C25 from TEXAS INSTRUMENTS. These devices were characterized to proton induced SEUs. But representativeness of SEU test results on processors was questioned during ARIANE5 studies. Protons test of these devices were also performed in the actual equipments with flight (or representative of) softwares. The results show that the On Board Computer and the Inertial Reference System can satisfy the requirements of the ARIANE5 missions.

Functional failure at low dose level (4 Krad(Si)) on voltage regulators (LM137) from different manufacturers are analysed. Dose rate effects on parts hardness are evaluated, showing that lowering the dose rate degrade more the IC's in the range 55 rad(Si)/s- 0,8 rad(Si)/s A failure mechanism is proposed, mainly based on circuit analysis, voltage contrast measurements, local irradiation and local electrical measurements with probe station. A spice simulation was performed, providing quantitative informations on the degradation. In the light of such a failure analysis and dose rate effects, practical implications on radiation assurance are discussed.

A Single Hard Error (SHE) characterization was performed on two types of 1Mbit SRAMs: MT5C1008 from MICRON and MSM8128 from HITACHI. On both types, test results showed that one single ion is sufficient to create a stuck bit. On orbit SHE rate calculation showed that the probability to have a stuck bit in space on a single 1Meg SRAM is rather low.

Hard errors from single heavy ions have been reported in advanced commercial CMOS memories. We examine the physical interactions of ions with MOS gate oxides - charge generation, recombination, transport and trapping. We also consider device and circuit characteristics. We conclude that hard errors from single ions are to be expected, and should not be considered surprising.

Recent heavy ion testing of high density SRAMs has revealed radiation induced hard errors: the errors show up as jammed bits in the memory. This phenomenon appears for high LET values. The Single Hard Errors (SHE) uniformly spread on the memory plane, disappear through UV escape and anneal very slowly. It is believed that the errors are due to local ionizing dose deposition. This phenomenon could become an important limitation to space electronic design with the growing integration of the devices.

Different part types of linear bipolar technology were irradiated in order to evaluate the ability of accelerated total dose testing to describe the tolerance at very low dose rate. On all tested types, the bias current was the most sensitive parameter. Results confirm that elevated temperature irradiation performed at high dose rate is well adapted to define the tolerance of the bias current at very low dose rate. The best accelerated test conditions correspond to a dose rate of 0.55 rad/s and irradiation temperature of 100 [degrees] C. However, such a procedure is not applicable to determine the behavior of the offset parameters at low dose rate.