CONTENTS

PREFACE

Since the loss of Telestar satellite in 1962, as a consequence of a high altitude nuclear test, it is known that natural or man-made radiation may perturb the operation of electronic equipments. Today, space vehicles highly rely on electronics and consequently space radiation effects must be considered at the design phase to guarantee the high-reliability and safety requirements of such projects. Even if spacequalified devices exist, so-called “hardened” with respect to radiation effects at the design and/or the manufacturing level, their high cost and lower performances compared with equivalent commercially available devices (Commercial Off The Shelf, COTS) make mass production components, not designed on purpose for space use, quasi mandatory for space applications. This constitutes a major challenge for the feasibility and success of future missions: on one hand it must be understood as far as possible both the nature and variability of space environment, on the other hand the consequences of this environment on electronic devices has to be evaluated taking into account the constant evolution of the technology and the large scope of device’s types.

Moreover, with the constant progress achieved in the manufacturing technologies, nano-electronics devices have features (transistor’s dimensions, operating frequencies) which make them potentially sensitive to the particles present in the Earth’s atmosphere, even at ground level. The very large presence of integrated circuits in all kind of applications result in a non negligible probability of transient errors, gathered under the acronym ‘SEE’ (Single Event Effects) resulting from the ionization generated by secondary particles issued from the nuclear reactions induced by the impact of atmospheric neutrons with atoms present in the silicon. This makes mandatory, for those applications requiring high reliability/safety, of considering this problem at the early application’s design phase to include the needed hardware/software fault tolerance mechanisms.

The estimation of the sensitivity to radiation of a device or architecture is a mandatory step to get an insight about the impact of radiation on the level of reliability/safety. Such a step requires both radiation ground testing, so-called accelerated tests, performed in radiation facilities such as particle accelerators or laser equipment and software tools modeling the applications environment. Such estimation, particularly when they deal with the Single Event Upset (SEU) phenomena, which results in the perturbation of the content of memory cells, may also require the realization of fault injection campaigns in which the consequences of radiation effects are taken into account at a level for which suitable description of the tackled device are available. The realization and exploitation of the results issued from such off-beam fault injection sessions constitute a source of precious information concerning both the estimation of the sensitivity to SEEs of the studied application and the identification of potential “week points” of a design or architecture supposed to be hardened.

This book aims at providing the reader with the major guidelines for coping with radiation effects on components supposed to be included in today’s application devoted to operate in space, but also in the atmosphere at high altitude or at ground

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