Reliability of M(O)EMS in harsh conditions: Space environment & Radiation effects on M(O)EMS

Size, mass and power consumption for devices and instruments are severely constrained on space missions. Therefore, space missions can benefit significantly of the MEMS technologies since they offer the advantages of low mass, low power consumption and reliability with novel capacities. Given the prohibitive costs of launching any payload into space (between 10 000 and 100 000 $ per kg) the trend during last decade has been towards “smaller, faster and cheaper” space missions. Several micro-spacecraft mission have been proposed or are currently under development.
The increased interest in using nanosatellites in space science missions is also due to the possibility to form nanosatellite constellation. Hundreds of small and lightweight nanosatellites can form an intelligent constellation acting as a distributed network of instruments.
Applications dedicated to space encounter particular and very often critical environment. Satellites or spacecraft are confronted to multiple effects that are encounter only in space. Space environment effects constitute a critical issue for the MEMS space qualification. The natural and induced space environment can cause a range of problems for spacecraft and space missions. Environmental factors include the natural radiation belts, solar energetic particles, cosmic rays, plasmas, gases, and "micro-particles", vacuum, extreme temperatures, vibrations…
We propose here a brief review of this space environment to understand the conditions that MEMS should be able to sustain during space missions. Then a brief description of this environment on failure mechanism is given. Finally, we will develop in particular the radiation-induced effect.

The simplest definition of reliability is quality over time. Since time is involved in reliability, it is often measured by a rate. Just as quality is usually measured in terms of rejects (or un-quality), reliability is measured in terms of failures (or un-reliability).