Science and Technology Facilities Council
Printable version E-mail this to a friend

Cosmic ray effect on microchips benefits from accelerated neutron testing

UK neutron scientists are tackling the challenge of cosmic radiation and its damaging effect on sensitive microchips in the aviation industry in the drive to develop more robust electronic equipment. Accelerated testing of microelectronic components at the Science and Technology Facilities Council’s STFC world leading ISIS neutron research centre replicates the effect of thousands of hours of flying time in just a few minutes.

When cosmic rays consisting of energetic particles originating from outer space, or the flow of fast-moving charged particles in the solar wind from the sun, collide with the Earth’s atmosphere they produce a cascade of lighter particles, a so-called ‘air shower’. High energy neutrons from air showers collide with microchips and upset or damage microelectronic devices. These occurrences known as ‘Single Event Effects’ (SEEs), can affect circuitry on the ground, but the problem is 300 times greater at high altitude. This makes it of particular concern to both the civil and military aerospace industry.

A microchip in an aircraft can be struck by a cosmic neutron every few seconds. When a neutron hits silicon, a nuclear reaction occurs causing an electrical charge shower that can interfere with the normal operation of electronic equipment.

Dr. Chris Frost, Project Leader of chip irradiation research at the ISIS neutron source explains the phenomenon.

‘A SEE occurs when a high energy particle in the atmosphere strikes sensitive regions of an electronic device, disrupting its correct operation. This can lead to temporary loss of RAM memory or even permanent burnout of equipment.’

Although SEEs have been recognised as an issue since 2001, the problem is being compounded by the drive for greater RAM density in computers. Smaller electronic circuitry is more vulnerable to this buffeting from neutrons.

One of the ways of tackling the issue is to test the quality and susceptibility of components under accelerated conditions. The ISIS neutron source, a world leading facility for research in the physical and life sciences, can replicate the experience of thousands of hours of flying time in a very condensed period. Dr Chris Frost says that by exposing components to neutron beams produced at ISIS, the industry can learn lessons about the best way forward.

’At ISIS we have the ability to produce intense beams of neutrons with similar energy ranges to those occurring naturally. This enables accelerated reliability testing of microelectric elements used in the aerospace industry. Once manufacturers understand where the biggest susceptibility problems lie, they can begin to redesign circuitry on a more robust basis.’

Initial tests occurred at the end of 2006 at the ISIS neutron source in Oxfordshire. A £140 million new ‘target station’ or neutron source is currently in the final stages of completion alongside the original ISIS neutron source. The plan, subject to funding, is for the ISIS Second Target Station to include a dedicated and full-time instrument to test the effects of SEEs and chip irradiation.

Results from this testing will allow manufacturers to mitigate against the problem and build triple redundancy into their electronic components. This increased confidence in the quality of electronic systems will help to make both civil and military aircraft safer.


Contacts
Martyn Bull
ISIS Communications & Media
Tel: + 44 (0) 1235 445805
Mob: + 44 (0) 7909 536983 (outside of office hours)
Email: m.j.bull@rl.ac.uk



Notes to Editors:

Images are available from http://www.stfc.ac.uk/PMC/PRel/STFC/Cosmic.aspx

In 2003 a consortium of aerospace companies backed by the DTI came together to start looking at the problem. MBDA, a leading aerospace systems company, heads the team known as SPAESRANE (Solutions for the Preservation of Aerospace Electronic Systems Reliability in the Atmospheric Neutron Environment). Other players in the group include BAE Systems, Smiths Aerospace and Goodrich Engine Control Systems.
ISIS Pulsed Neutron and Muon Source

ISIS is a world-leading centre for research in physical and life sciences operated by the Science and Technology Facilities Council at the Rutherford Appleton Laboratory, Didcot, Oxfordshire, UK.

ISIS supports an international community of over 2000 scientists who use neutrons and muons for research in physics, chemistry, materials science, geology, engineering and biology. It is the most productive research centre of its type in the world.

Neutron scattering is a vital research and analysis technique in exploring the structure and dynamics of materials and molecules. It provides unique and complementary information to that available from synchrotron light sources.

The ISIS Second Target Station Project complements the facilities already operating at ISIS and enables the science programme to expand into the key research areas of soft matter, advanced materials and bio-science. The experimental programme at the new target station will begin in October 2008.

About STFC


Science and Technology Facilities Council The Science and Technology Facilities Council ensures the UK retains its leading place on the world stage by delivering world-class science; accessing and hosting international facilities; developing innovative technologies; and increasing the socio-economic impact of its research through effective knowledge exchange partnerships.

The Council has a broad science portfolio including Astronomy, Particle Physics, Particle Astrophysics, Nuclear Physics, Space Science, Synchrotron Radiation, Neutron Sources and High Power Lasers. In addition the Council manages and operates three internationally renowned laboratories:

• The Rutherford Appleton Laboratory, Oxfordshire
• The Daresbury Laboratory, Cheshire
• The UK Astronomy Technology Centre, Edinburgh.

The Council gives researchers access to world-class facilities and funds the UK membership of international bodies such as the European Laboratory for Particle Physics (CERN), the Institute Laue Langevin (ILL), European Synchrotron Radiation Facility (ESRF), the European organisation for Astronomical Research in the Southern Hemisphere (ESO) and the European Space Agency (ESA). It also contributes money for the UK telescopes overseas on La Palma, Hawaii, Australia and in Chile, and the MERLIN/VLBI National Facility, which includes the Lovell Telescope at Jodrell Bank Observatory.

The Council distributes public money from the Government to support scientific research. Between 2007 and 2008 we will invest approximately £678 million.

The Council is a partner in the UK space programme, coordinated by the British National Space Centre.

Facing the Future...find out more