Multi-Poisson Process Analysis of Real-Time Soft-Error Rate Measurements in Bulk 65nm SRAMs

International audienceAltitude and underground real-time soft error rate (SER) measurements on SRAM circuits have been analyzed in terms of independent multi-Poisson processes describing the occurrence of single events as a function of bit flip multiplicity. Applied for both neutron-induced and alpha particle-induced SERs, this detailed analysis highlights the respective contributions of atmospheric radiation and alpha contamination to multiple cell upset mechanisms. It also offers a simple way to predict by simulation the radiation response of a given technology for any terrestrial position, as illustrated here for bulk 65nm SRAMs

Charge Collection Physical Modeling for Soft Error Rate Computational Simulation in Digital Circuits

This chapter describes a new computational approach for accurately modeling radiation-induced single-event transient current and charge collection at circuit level. This approach, called random-walk drift-diffusion (RWDD), is a fast Monte Carlo particle method based on a random-walk process that takes into account both diffusion and drift of carriers in a non-constant electric field both in space and time. After introducing the physical insights of the RWDD model, the chapter details the practical implementation of the method using an object-oriented programming language and its parallelization on graphical processing units. Besides, the capability of the approach to treat multiple node charge collection is presented. The chapter also details the coupling of the model either with an internal routine or with SPICE for circuit solving. Finally, the proposed approach is illustrated at device and circuit level, considering four different test vehicles in 65 nm technologies: a stand-alone transistor, a CMOS inverter, a SRAM cell and a flip-flop circuit. RWDD results are compared with data obtained from a full three-dimensional (3D) numerical approach (TCAD simulations) at transistor level. The importance of the circuit feedback on the charge-collection process is also demonstrated for devices connected to other circuit nodes

Single-Event-Transient Effects in Junctionless Double-Gate MOSFETs with Dual-Material Gate Investigated by 3D Simulation

International audienceThe Junctionless Double-Gate MOSFET combined with a Dual-Material Gate (JL-DMDG) is interesting for future ultra-scaled devices thanks to a simplified technological process (no junctions), reduced leakage currents and capability to reduce SCEs and HCEs (due to the step in the potential profile). In this work, we investigate the bipolar amplification and charge collection in JL-DMDG submitted to heavy-ion irradiation. We show that JL-DMDG is more sensitive to radiation than more conventional devices with single-material-gate or operating in inversion-mode

Basic single-event mechanisms in Ge-based nanoelectronics subjected to terrestrial atmospheric neutrons

International audienceGermanium is potentially candidate to replace silicon in ultra-scaled transistors. This work analyses the radiation response of germanium in thin layer subjected to atmospheric neutrons simulated with Geant4 and quantifies the underlying mechanisms potentially responsible of single event effects in Ge-based CMOS technologies. From this analysis of interactions at material-level, reliability assessments for Gebased nanoelectronics are tentatively deduced for technological nodes ranging from 180 nm to 5 nm in terms of nature and number of nuclear events susceptible to upset a SRAM memory cell. Finally, first soft error rate projections are performed for germanium SRAMs in 130, 65 and 40 nm based on a simulation methodology previously developed and fully validated on silicon memories also characterized by real-time experiments

Origin of High Total Dose Sensitivity on the OP400 Bipolar Operational Amplifier

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Modeling and Simulation of SEU in Bulk Si and Ge SRAM

International audienceIn this work, the random-walk drift-diffusion (RWDD) model has been coupled to a circuit simulator to investigate single event upsets (SEU) induced by alpha particles in SRAM cells with silicon or germanium as bulk material. The impact of semiconductor charge generation and transport properties on the SEU mechanisms is quantified and discussed in a first-order approach considering ideal materials and generic devices. Our results suggest that the radiation response of Ge-based SRAM should be similar to the one observed for Si-SRAM, the benefits of higher mobilities at circuit level for germanium offsetting the negative impact of a relatively low energy value for electron-pair creation on transient current pulse magnitudes

A water tank muon spectrometer for the characterization of low energy atmospheric muons

International audienceIn this work, a water tank muon spectrometer was designed, assembled and operated to measure the energy distribution of low energy atmospheric muon flux induced by cosmic-rays at sea level in the energy range 100-500 MeV. The principle of this experiment is to use water as muon moderator inserted between two coincidence detectors to select the cutoff energy below which muons can no longer be detected. The differential and integral muon spectra are then derived from successive measurements by varying the liquid height within the water tank. The instrument was entirely characterized and modeled in terms of detector efficiency, cutoff energy and counting rate. Experimental data are reported for the energy distribution of muon flux at sea level (43°N of latitude) and finally compared with literature survey

Natural Radiation Effects in CCD devices

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Natural Radiation Effects in CCD devices

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Multi-Poisson process analysis of real-time soft-error rate measurements in bulk 65 nm and 40 nm SRAMs

28th European Symposium on the Reliability of Electron Devices, Failure Physics and Analysis (ESREF), Bordeaux, FRANCE, SEP 25-28, 2017International audienceAltitude and underground real-time soft error rate (SER) measurements on SRAM circuits have been analyzed in terms of independent multi-Poisson processes describing the occurrence of single events as a function of bit flip multiplicity. Applied for both neutron-induced and alpha particle-induced SERB, this detailed analysis highlights the respective contributions of atmospheric radiation and alpha contamination to multiple cell upset mechanisms. It also offers a simple way to predict by simulation the radiation response of a given technology for any terrestrial position, as illustrated here for bulk 65 nm and 40 nm SRAMs. (C) 2017 Elsevier Ltd. All rights reserved