Life issues, robustness consequences and reliability challenges for Very Deep Sub Micron technologies

Reliability and robustness are strongly linked: aging amplifies robustness issues while environmental stress accelerates aging. As Very Deep Sub Micron (VDSM) technologies offer early wear out and intrinsically lower margins, lifetime and EMC become a coupled challenge that underlines the need of a complete and multidisciplinary approach joining EMC, reliability, device characterization and internal testing skills. Trends, proof of evidence and internal testing approach are described in order to emphasize the need of device aging consideration in robustness studies.

I. Introduction

Reliability is a key issue for space applications. Satellites are expensive and out of repair in case of breakdown. They are designed to offer long life in orbit (more than 15 years for telecommunication applications) in a harsh environment (vacuum, space charging, radiation…). There are plenty of formal way to define reliability but if we consider its purpose, it is mostly the ability for a system to properly work for a given mission profile that correspond to a sequence of expected amounts of time in specific environments at given electrical conditions.