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The use of commercial electronics in space dates back more than two decades. However, for many years, its use was limited and based on careful radiation response evaluation relying on well-established testing practices. As the access to space was eased during the last decade, new actors, capable of building satellites at a reduced cost, e.g., Cubesats and small satellites, appeared on the space scene. These products are now based on full commercial solutions that helps reducing costs and are compatible with tight launch schedules. On the opposite, the radiation threat to reliability has not been tackled in such an effective way and the possibility of early failures is a more and more serious concern for space agencies because of the incremental space debris. A typical example is that of mega-constellations for ground communications. Hence, space missions now also deal with distributed systems, a similar situation as that of CERN when it comes to ensuring the reliability against radiation effects of accelerator equipment.

“This opened a window of opportunities for collaboration between space entities and high-energy accelerators that deals with a number of new space needs, both in terms of emerging radiation effects of concern, the development of leaner verification practices and the construction of novel radiation facilities that can be up to the challenge”, says Coronetti.

The emerging threat

Standard space system reliability had to deal only with very high energy particles, such as galactic cosmic ions and trapped high-energy protons. However, state-of-the-art commercial electronic devices are based on transistors whose characteristic sizes are now not larger than a few hundreds of atoms (i.e., less than 100 nm). In conjunction with the tendency towards low-power systems, this makes commercial devices vulnerable to the weakly ionizing particles of the radiation field, such as the low-energy protons.

The dissertation provides deep insight into the modelling of bit-flips happening in memory-based devices that are used for fast computations in space computers. The dissertation also shows unprecedented sensitivity for operation in low-Earth orbits that may pose a serious concern to future space missions.

“In the coming years, we shall expect low-energy proton testing to become a more diffused and well-established practice for the standard qualification of space systems. The RADEF facility at JYU is well-positioned to answer this increasing industrial demand for low-energy proton testing”, says Coronetti.

The new opportunities

One additional feature of state-of-the-art commercial electronics are the novel design rules that manufacturers have been implementing to enable the continuous miniaturization of their products. In order to achieve standard qualification, expensive procedures have to be put in place to enable the testing of the devices with weakly penetrating particle beams. However, even these expensive techniques are becoming inefficient in rendering testable devices characterized by three-dimensional stacking of chips.

Therefore, space agencies and industry are looking for alternatives that allow determining the radiation response of not only devices, but even boards, modules and entire systems, in a fast and efficient way. The two best options in this context are high-energy hadrons and high-energy heavy ions.

The dissertation defines the possibilities and caveats offered by testing in a high-energy hadron environment such as that of the CHARM facility at CERN. The dissertation focuses on the most physics-related aspects, such as the expected radiation effects and how to link the results to what could be observed in space. The dissertation material stands at the basis of a recently published guideline for the verification of space systems that benefited from the expertise of NASA, ESA, CNES and Airbus.

“The interest of so many international players in space exploration towards a collaboration with CERN for the development of a guideline for system-level testing will be beneficial to both their sub-contractors and to all other small satellite stakeholders”, says Coronetti.

The dissertation is published in JYU Dissertations series, number 453, Jyväskylä 2021, ISSN 2489-9003, ISBN 978-951-39-8915-6 (PDF). Link to publication: 

M.Sc. Andrea Coronetti defends his doctoral dissertation "Relevance and guidelines of radiation effect testing beyond the standards for electronic devices and systems used in space and at accelerators" on 17 November 2021 at 12 noon. Opponent Professor Jean-Luc Autran (Aix-Marseille University, France) and Custos Senior Researcher Arto Javanainen (Ģ��ֱ��). The doctoral dissertation is held in English.

The audience can follow the dissertation in the lecture hall or online.

Link to the Zoom Webinar event (Zoom application or Google Chrome web browser recommended): 

Phone number to which the audience can present possible additional questions at the end of the event (to the custos): +358406146881