R. Harboe-Sorensen

A verified proton induced latch-up in space (CMOS SRAM)

An instrument on the polar ERS-1 satellite failed following a transient high current consumption. The failure was found to have occurred close to the center of the South Atlantic Anomaly. Ground test showed certain memories to be sensitive to proton-induced latchup. The failure was concluded to be due to latchup during exposure to South Atlantic Anomaly protons. The authors believe that this to be the first time a verified proton-induced latchup in space has been reported. >

Heavy Ion Testing and 3-D Simulations of Multiple Cell Upset in 65 nm Standard SRAMs

Heavy ions experiments are carried out on commercial 90 nm and 65 nm SRAMs. The contribution of single and multiple cell upsets (MCUs) are discussed as a function of the LET for different memory cell areas and for triple well usage. Once again, well engineering plays a key role on MCU and SEE response of SRAM. Full 3-D TCAD simulations investigate the occurrence of parasitic bipolar effect.

Multiple-Bit Upset Analysis in 90 nm SRAMs: Heavy Ions Testing and 3D Simulations

SEU and MBU cross-sections are measured with heavy ions for commercial 90 nm single port and dual port SRAMs. SEU and MBU rates are discussed as a function of the LET and beam tilt. A new sensitive area devoted to MBU is computed with full 3D TCAD simulations on single and adjacent memory cells.

Observation and prediction of SEU in Hitachi SRAMs in low altitude polar orbits

In-orbit SEU (single event upset) data from three microsatellites are separated into galactic cosmic ray (GCR), South Atlantic anomaly (SAA) and solar flare upsets. Heavy ion and proton testing of the same devices is reported, and predictions using LET (linear energy transfer)-dependent ion cross sections and a two-parameter fit to proton cross section data are compared with in-flight data. SEU trends in memory devices from a single manufacturer, from 16 kb to 4 Mb, are identified. The increasing density of the memories is found to be accompanied by an apparent decreasing sensitivity to the heavy ion environment in polar orbit. Although the LET threshold decreases, the decrease in asymptotic cross section has a greater effect. However, the sensitivity to proton-induced upsets is nearly similar in all memories, so the proton effects become dominant by an order of magnitude. This has important implications for future spacecraft with large onboard memories and high performance processors. >

Angular Dependence of Heavy Ion Effects in Floating Gate Memory Arrays

Single, high energy, high LET, ions impacting on a Floating gate array on grazing or near-grazing angles lead to the creation of long traces of FGs with corrupted information. Up to 30 consecutive devices can be involved in the trace left by a single ion. We demonstrate that charge collection at multiple nodes can be expected as the technology advances. One of the major implications is that the widely adopted cosine law should be used with great care when dealing with modern devices, with sizes smaller than 100 nm.

The SEU Risk Assessment of Z80A, 8086 and 80C86 Microprocessors Intended for Use in a Low Altitude Polar Orbit

This paper presents the results of a test and analysis program carried out in support of an Earth Resources Satellite project in order to provide a quantitative SEU risk assessment for certain microprocessor based subsystems. The key features of the program were the low cost and comparative simplicity of the test techniques which, nevertheless, provided sufficient data for a quantitative risk assessment using the CREME suite of programs.

TID and SEE Tests of an Advanced 8 Gbit NAND-Flash Memory

We report on the dose and operational mode dependence of error percentage, stand-by current, erase and write time of 8 Gbit / 4 Gbit NAND-flash memories as well as on their static, dynamic and SEFI cross sections.

Key Contributions to the Cross Section of NAND Flash Memories Irradiated With Heavy Ions

Heavy-ion irradiation of NAND flash memories under operating conditions leads to errors with complex, data-dependent signatures. We present upsets due to hits in the floating gate array and in the peripheral circuitry, discussing their peculiarities in terms of pattern dependence and annealing. We also illustrate single event functional interruptions, which lead to errors during erase and program operations. To account for all the phenomena we observe during and after irradiation, we propose an ldquoeffective cross section,rdquo which takes into account the array and peripheral circuitry contributions to the SEU sensitivity, as well as the operating conditions.

Observation and analysis of single event effects on-board the SOHO satellite

SOHO, the European Space Agency (ESA) solar observation satellite, has experienced a large number of single event effects (SEEs) since its launch in December 1995. This paper details events believed to be induced by cosmic rays or protons. Self-switch-off power supply events in the service module and in the payload module will be detailed as well as single event upsets (SEUs) in the solid-state recorder (SSR) and in the global oscillation at low frequency (GOLF) instrument. Power system events are believed to originate from transient SEUs in linear components. SSR and GOLF SEUs are seen to respond to solar particle events. Relevant ground verification testing will be presented and upset predictions are compared with observations.

From the Reference SEU Monitor to the Technology Demonstration Module On-Board PROBA-II

The reference SEU Monitor system designed and presented in 2005 (R. H. SOslashrensen, F.-X. Guerre, and A. Roseng ldquoDesign, testing and calibration of a reference SEU monitor system,rdquo in Proc. RADECS, 2005, pp. B3-1-B3-7) has now been used by many researchers at many radiation test sites and has provided valuable calibration data in support of numerous projects. As some of these findings and results give new insight into improved inter-facility calibrations and provide additional inputs into ongoing SEE research, a few of the more interesting cases are presented. Furthermore the dasiadetector elementpsila, the Atmel AT60142F SRAM, now in a hybrid configuration, will form the key detector element in the Technology Demonstration Module (TDM) to be flown on-board the PROBA-II satellite, to be launched at the beginning of 2009. This flight opportunity extends the Reference SEU Database with both ground and space data, taken on the same device under identical operating conditions. Additionally, the Reference SEU Monitor concept is employed as the basis for the new Reference SEL Monitor system, currently under characterization and preparation for integration on the TDM. Ground SEU/SEL characterization of this latch-up experiment is also presented as well as the basic concept of the TDM, the PROBA-II Radiation Monitor module.