Dynamic Test Methods for COTS SRAMs

International audience; In previous works, we have demonstrated the importance of dynamic mode testing of SRAM components under ionizing radiation. Several types of failures are difficult to expose when the device is tested under static (retention) mode. With the purpose of exploring and defining the most complete testing procedures and reveal the potential hazardous behaviors of SRAM devices, we present novel methods for the dynamic mode radiation testing of SRAMs. The proposed methods are based on different word address accessing schemes and data background: Fast Row, Fast Column, Pseudorandom, Adjacent (Gray) and Inverse Adjacent (Gray). These methods are evaluated by heavy ion and atmos…

Heavy-Ion Radiation Impact on a 4Mb FRAM under Different Test Conditions

The impact of heavy-ions on commercial Ferroelectric Memories (FRAMs) is analyzed. The influence of different test modes (static and dynamic) on this memory is investigated. Static test results show that the memory is prone to temporary effects occurring in the peripheral circuitry. Dynamic tests results show a high sensitivity of this memory to heavy-ions.

Heavy-Ion-Induced Degradation in SiC Schottky Diodes : Incident Angle and Energy Deposition Dependence

International audience; Heavy-ion-induced degradation in the reverse leakage current of SiC Schottky power diodes exhibits a strong dependence on the ion angle of incidence. This effect is studied experimentally for several different bias voltages applied during heavy-ion exposure. In addition, TCAD simulations are used to give insight on the physical mechanisms involved.

Heavy-Ion Radiation Impact on a 4 Mb FRAM Under Different Test Modes and Conditions

International audience; The impact of heavy-ions on commercial Ferroelectric Memories (FRAMs) is analyzed. The influence of dynamic and static test modes as well as several stimuli on the error rate of this memory is investigated. Static test results show that the memory is prone to temporary effects occurring in the peripheral circuitry, with a possible effect due to fluence. Dynamic tests results show a high sensitivity of this memory to switching activity of this peripheral circuitry.

SEGR in SiO<inf>2</inf>-Si<inf>3</inf>N<inf>4</inf> stacks

Single-event effects of space and atmospheric radiation on memory components

Electronic memories are ubiquitous components in electronic systems: they are used to store data, and can be found in all manner of industrial, automotive, aerospace, telecommunication and entertainment systems. Memory technology has seen a constant evolution since the first practical dynamic Random- Access Memories (dynamic RAMs) were created in the late 60's. The demand for ever-increasing performance and capacity and decrease in power consumption was met thanks to a steady miniaturization of the component features: modern memory devices include elements barely a few tens of atomic layers thick and a few hundred of atomic layers wide. The side effect of this constant miniaturization was a…

Incident angle effect on heavy ion induced reverse leakage current in SiC Schottky diodes

Heavy-ion induced degradation in the reverse leakage current of SiC Schottky power diodes shows distinct dependence on the angle of incidence. TCAD simulations have been used to study the physical mechanisms involved.

Heavy Ion Induced Degradation in SiC Schottky Diodes : Bias and Energy Deposition Dependence

Experimental results on ion-induced leakage current increase in 4H-SiC Schottky power diodes are presented. Monte Carlo and TCAD simulations show that degradation is due to the synergy between applied bias and ion energy deposition. This degradation is possibly related to thermal spot annealing at the metal semiconductor interface. This thermal annealing leads to an inhomogeneity of the Schottky barrier that could be responsible for the increase leakage current as a function of fluence. peerReviewed

SEGR in SiO${}_2$–Si$_3$N$_4$ Stacks

Abstract. This work presents experimental Single Event Gate Rupture (SEGR) data for Metal–Insulator–Semiconductor (MIS) devices, where the gate dielectrics are made of stacked SiO2–Si3N4 structures. A semi-empirical model for predicting the critical gate voltage in these structures under heavy-ion exposure is first proposed. Then interrelationship between SEGR cross- section and heavy-ion induced energy deposition probability in thin dielectric layers is discussed. Qualitative connection between the energy deposition in the dielectric and the SEGR is proposed. peerReviewed

A Methodology for the Analysis of Memory Response to Radiation through Bitmap Superposition and Slicing

A methodology is proposed for the statistical analysis of memory radiation test data, with the aim of identifying trends in the single-even upset (SEU) distribution. The treated case study is a 65nm SRAM irradiated with neutrons, protons and heavy-ions.

Soft errors in commercial off-the-shelf static random access memories

International audience; This article reviews state-of-the-art techniques for the evaluation of the effect of radiation on static random access memory (SRAM). We detailed irradiation test techniques and results from irradiation experiments with several types of particles. Two commercial SRAMs, in 90 and 65 nm technology nodes, were considered as case studies. Besides the basic static and dynamic test modes, advanced stimuli for the irradiation tests were introduced, as well as statistical post-processing techniques allowing for deeper analysis of the correlations between bit-flip cross-sections and design/architectural characteristics of the memory device. Further insight is provided on the …

Real-Time SRAM Based Particle Detector

International audience; Monitoring radiative environments is of great importance, especially for facilities hosting large particle accelerators and nuclear power plants. Such facilities make use of monitoring systems that are usually composed of different sensors to evaluate the intensity of the ambient radiation field in different locations. In this paper, we propose an SRAM-based monitor that works in dynamic mode (memory continuously accessed), according to data gathered by irradiating our sensor in several particle accelerator facilities. The dynamic mode of operation allows for real-time sensing, especially when the particle fluence is high. In order to ensure the efficiency of the det…

SEE on Different Layers of Stacked-SRAMs

International audience; This paper presents heavy-ion and proton radiation test results of a 90 nm COTS SRAM with stacked structure. Radiation tests were made using high penetration heavy-ion cocktails at the HIF (Belgium) and at RADEF (Finland) as well as low energy protons at RADEF. The heavy-ion SEU cross-section showed an unusual profile with a peak at the lowest LET (heavy-ion with the highest penetration range). The discrepancy is due to the fact that the SRAM is constituted of two vertically stacked dice. The impact of proton testing on the response of both stacked dice is presented. The results are discussed and the SEU cross-sections of the upper and lower layers are compared. The …

Single-Event Effects in the Peripheral Circuitry of a Commercial Ferroelectric Random Access Memory

International audience; This paper identifies the failure modes of a commercial 130-nm ferroelectric random access memory. The devices were irradiated with heavy-ion and pulsed focused X-ray beams. Various failure modes are observed, which generate characteristic error patterns, affecting isolated bits, words, groups of pages, and sometimes entire regions of the memory array. The underlying mechanisms are discussed.

Investigation on MCU Clustering Methodologies for Cross-Section Estimation of RAMs

International audience; Various failure scenarios may occur during irradiation testing of SRAMs, which may generate different characteristic Multiple Cell Upset (MCU) error patterns. This work proposes a method based on spatial and temporal criteria to identify them.

Low Energy Protons at RADEF - Application to Advanced eSRAMs

A low energy proton facility has been developed at RADEF, Jyvskyl, Finland. The proton energy selection, calibration and dosimetry are described. The first experiment with external users was performed using two memory test vehicles fabricated with 28 nm technology. Examples of single event upset measurements in the test vehicles embedded SRAMs (eSRAMs) as a function of proton energy are provided.

Methodologies for the Statistical Analysis of Memory Response to Radiation

International audience; Methodologies are proposed for in-depth statistical analysis of Single Event Upset data. The motivation for using these methodologies is to obtain precise information on the intrinsic defects and weaknesses of the tested devices, and to gain insight on their failure mechanisms, at no additional cost. The case study is a 65 nm SRAM irradiated with neutrons, protons and heavy ions. This publication is an extended version of a previous study.