Cosmic rays threatening electronics user Cosmic rays, a threat to electronics
Due to their miniaturization, electronic components are increasingly exposed to cosmic radiation. From outer space to cars, the alert is growing. Why do cosmic rays threaten electronics users?
At the beginning of February 2022, in the American sky. About forty satellites supposed to join SpaceX’s Starlink constellation are burning up in the atmosphere. A destruction occurred a few hours after their launch from the Kennedy Space Center (Florida). A solar wind would be the cause of the incident. This magnetic storm – at the origin of the aurora borealis – would have caused a densification of the atmosphere, causing the satellites to lose speed and then fall.
It must be said that SpaceX has opted for a unique strategy, consisting of transiting its machines in a temporary orbit located at an altitude of 210 km, in the middle of the upper atmosphere. This means that only satellites in good working order can then be sent into space. Is Elon Musk the only one who has to worry about solar winds? Not so sure…
Because radiation from space represents another danger, much more worrying: that of its direct effect on electronic components. Radiation from the cosmos, solar flares and other coronal mass ejections from the sun generate a cocktail of radiation composed of heavy ions, protons and electrons. Charged particles that can cause short circuits, change the state of bits in memories, or even destroy components.
What is cosmic radiation made of?
Cosmic radiation is mainly made up of charged particles: protons (88%), helium nuclei (9%), antiprotons, electrons, positrons and neutral particles (gamma rays, neutrinos and neutrons). The source of this radiation is located, depending on the case, in the Sun, inside or outside our galaxy. Some of the astroparticles that make up cosmic radiation have an energy that exceeds 1020 eV and that is not explained by any identified physical process.
Solutions, but expensive
With new space, come actors who send satellites into space without having ensured that their electronic components will be able to withstand the space environment.
Ronan Marec, radiation expert at Thales Alenia Space
First faced with the consequences of cosmic rays, space players quickly adopted protection solutions. “Error correctors are systems that detect a logical hazard and correct it,” explains Frédéric Wrobel, teacher at the Institute of Electronics and Systems in Montpellier. Other countermeasures are possible, such as system redundancy and specific transistor designs. But between the implementation of these hardening technologies and the robustness tests, the bill can soar.
Spatial distribution of sources of cosmic gamma rays with energies above 100 MeV. Their distribution also gives clues to the origin of the particle radiation. The bright band is the Milky Way, with its center at the center. , Public domain, via Wikimedia Commons
Cosmic rays threaten electronics and what is the effect on electronics?
Cosmic rays are energetic enough to alter the state of an electronic component of an integrated circuit, which can cause transient errors, such as data corruptions in the random access memory as well as poor execution of the processor, often called errors. “soft error (en)” (not to be confused with software errors caused by programming errors or a bug). This was a problem for electronics at very high altitudes, such as satellites, but with transistors getting smaller and smaller, it becomes a bigger concern. Studies by International Business Machines (IBM) in the 1990s suggest that computers experience approximately one error per 256 megabytes of RAM per month due to cosmic rays.
To reduce this problem, Intel has proposed a cosmic ray detector that could be integrated into future microprocessors with low etching fineness, allowing the processor to re-execute the last command following the cosmic ray18. Cosmic rays are suspected to be the cause of a 2008 flight incident where a Qantas Airbus A330 airliner plunged twice over a hundred meters after an unexplained malfunction in the autopilot. Several passengers and crew members were injured, some seriously.
After this incident, accident investigators determined that the flight control system received an unexplained data spike, and the entire system was functioning perfectly. A software update has been made in all A330 and A340 airliners worldwide, allowing these data peaks to be electronically filtered.
To counter these effects on microelectronics, there are radiation hardening techniques.
The hardening of electronic components against ionizing radiation refers to a method of designing, manufacturing and testing electronic systems and components to make them resistant to malfunctions and degradation caused by electromagnetic radiation and energetic subatomic particles encountered during spaceflight or in space. high altitude, as well as in the environment of nuclear reactors, even during military operations.
Most of the components “hardened” against ionizing radiation are adaptations of components on the market, produced using processes intended to limit the effects of radiation on the materials of which they are made. Due to the complexity of these adaptations, the development of such components, intended for a niche market, is time-consuming and expensive. This is the reason why these components offer performances that are often very much behind their contemporary equivalents on the market.
Photo description: simulation of the showers generated in the interaction of cosmic rays with the earth’s atmosphere.