18 Sep 2009



Instrument for rapid testing of effects of high energy neutrons

​​​​​Chipir in ISIS TS2 Design Drawing

​Instrument for rapid testing of high energy neutron effects

Chipir is one of the first dedicated facilities outside of the US to look at how silicon microchips respond to cosmic neutron radiation. The instrument offers users the ability to perform electronics testing at highly accelerated rate with a measurement of just one hour being equivalent to exposing microchips to high-energy neutrons for hundreds to thousands of years in the real environment. Such accelerated atmospheric neutron testing is designed to mimic the real disruptions and failure, the so-called ‘single event effects’ experienced by electronics, and allow industry to develop strategies, designs and methods to mitigate their effects

A ‘single event effect’ (SEE) describes the disruption of a microelectronic device upon interaction with a single subatomic particle. These subatomic particles are generated when high energy cosmic rays collide with the earth’s atmosphere generating cascading showers of electromagnetic and secondary particle radiation – including a flux of high energy neutrons.

“These high energy neutrons and protons are problematic because they interact with semiconductor material – on the ground or aboard aircraft –where they give rise to lower energy protons nuclear recoils and other secondary charged particles. These deposit a small amount of electronic charge causing SEE’s” Royal Academy of Engineering, Extreme space weather: impacts on engineered systems and infrastructure.

At normal aircraft altitudes of 10-12km this atmospheric the component of the cosmic ray radiation that causes these problems consists mostly of neutrons. It’s these neutrons that are capable of delivering either a whole plethora of potential problems. These include soft errors – single or multiple upsets in the electronic devices which corrupt memory or change logic function and hard errors – catastrophic errors, which result in permanent damage and ultimately electronic failure.

“Single event effects generated by atmospheric neutrons have been known for many years to be a dominant threat to the strict high reliability requirements of aircraft avionics. With increased miniaturisation, complexity, higher speeds and greater prevalence of embedded micro-electronic systems, this also means that inevitably we are seeing SEE problems, known to occur at altitude of aerospace and avionic industries, emerge in terrestrial ground based systems.” Dr Chris Frost, ISIS.

The Chipir facility presents the solution to these problems by combining world class instrumentation with world leading expertise.

  • CHIPIR can operate in two interchangeable ‘modes’ providing both a collimated ‘pencil’ neutron beam for individual devices and an isotropic ‘flood’ neutron beam to allow very large systems to be tested.
  • The neutron beam extends to energies up to 800 MeV.
  • The profile of the differential energy spectrum of the beam is designed to match that of the atmospheric spectrum with a high neutron flux of >1x106 n/cm2/s.
  • Attenuators will be used to remove the thermal neutron component of the incident beam
  •  Easy cable access and routes between the sample area and data logging area allows user specific cabling to be easily installed
  •  Multitude of EU, US and UK power is provided in the experimental areas

 “ISIS is one of few facilities in the world capable of producing enough high energy neutrons to perform accelerated testing. The new Chipir instrument at ISIS will be the best screening facility in the world” Andrew Chugg, Technical chair of RADECS, 2003-2013.

Contact information for Chipir

Location and contact information for the Chipir instrument​