Space Radiation Tested on Prototype Chip

A new radiation-hardened semiconductor chip has been tested using state-of-the-art the Australian Nuclear Science and Technology Organisation (ANSTO) technology. The memory chip was developed by a team led by scientist Dr Jafar Shojaii, Senior Research Fellow at Swinburne University and Honorary Fellow at the University of Melbourne, and with partners from INFN (Italian Instituto Nazionale de Fisica Nucleare) and the University of Milan.   

The memory chip was developed for use in environments prone to high amounts of radiation, including high energy accelerators or nuclear facilities, or in space. Electronics in high-radiation environments are susceptible to single event upsets (SEUs) and single event effects (SEEs) - problems that disrupt the operation of electronic systems. This new prototype SRAM memory chip was designed with a new architecture using an original approach to eliminate these events. 

“The impact of radiation damage to the performance of the newest generations of microelectronic technologies is still not very well understood in the scientific community,” explained Dr Shojaii.

“Only an experiment can confirm that the performance of the technology will not be adversely impacted by radiation.”

“We need to validate that the hundreds of millions of transistors in a single chip will perform suitably at the device level, before use in space. The radiation effects on semiconductor chips have been one of the main reasons for satellite failures in space missions,” he said. 

The chip prototype was tested using the high-energy ion microprobe on the SIRIUS ion accelerator at ANSTO’s Centre for Accelerator Science. Exposure to environments like space was simulated by exposing selected parts of the prototype chip to a beam of carbon ions or protons in a vacuum. These types of particles are abundant in Lower Earth Orbits. 

“The novelty of testing at the Centre for Accelerator Science is that the nuclear microprobe enables high-precision irradiation with sub-micrometre accuracy by means of computer-controlled rapid scanning,” said Dr Shojaii.

“This mode of irradiation testing allows us to investigate a SEE in a selected chip circuitry while ensuring other vital chip parts that remain intact.“

The custom chip was tested under a variety of laboratory conditions such as different particle mass and energy, increasing particle rate, and increasing accumulated dose over the course of three experiments performed at ANSTO over the past year. The new chip proved to be radiation hard for threshold doses of hundreds of kiloRads and particle rates up to 10 MHz. The chip was also able to withstand very high doses up to 100 MegaRad range, which is required by the high energy accelerator community, such as the Large Hadron Collider experiment at CERN in Switzerland.  

Dr Stefania Perracchi,  an accelerator beamline scientist at the Centre for Accelerator Science, who specialises in radiation dosimetry and also collaborated on the experiments, also commented on the increasing use of the Centre for irradiation testing.

“Precision irradiation is used on advanced material and device prototypes in testing for space, health, biology, electronics, communication, energy and quantum science. It is quickly becoming one of the Centre’s core capabilities.”

Dr Pastuovic, a senior accelerator scientist at ANSTO’s Centre for Accelerator Science, who specialises in applications for advanced materials and device technologies, also commented: “The Sirius accelerator system coupled to multiple instrument beamlines is one of ANSTO's and Australia's flagship research facilities for applied science, and it is well-suited for the characterisation and testing of materials in radiation hard environments,” he said. 

“The ability of expert staff to model and prepare experiments, fabricate and customise technology on-site in real-time is indispensable in complex measurements for high-tech [research and development].”

This latest research using ANSTO facilities comes just after the organisation’s announcement of a collaboration on a heater unit with Ouranos Systems.

Video Credit: ANSTO.