Paragraf has demonstrated the capability of its graphene Hall Effect sensors to resist high levels of radiation. The discovery, based on testing from the NPL, proves that ‘unpackaged’ Hall Effect sensors can be employed in high-radiation environments such as space. The project was funded by Innovate UK.
Used to measure the magnitude of a magnetic field, sensors are a crucial electronic component in a mixture of applications, from proximity sensing and speed detection through to current sensing. However, historically, their deployment in high-radiation environments, which includes satellites and nuclear power plants has faced considerable challenges. This is due to conventional sensors made from silicon and other semiconductor materials reacting adversely to neutron radiation unless they are encapsulated in radiation-hardened packaging. This employs a more complex, lengthy and costly manufacturing process and may need the sensor to be replaced over time if, for example, the packaging is damaged.
By contrast, tests conducted by NPL have demonstrated that following exposure to a neutron dose of 241mSv/hour – which is about 30,000 times the expected typical neutron dose rate in the ISS - the company's graphene Hall Effect sensors are not impacted by this level of radiation. This is the first time that a commercially available, graphene-based electronic device has been demonstrated to be impervious to neutron irradiation.
Ivor Guiney, co-founder of Paragraf, commented: “NPL’s findings have the potential to be a game changer when it comes to high-performance satellites and other critical high-radiation applications such as nuclear decommissioning. Due to the exceptional mechanical strength and high transparency of graphene, our Hall Effect sensor can be used reliably in high-radiation applications without requiring packaging. This is key to improving reliability and durability while reducing manufacturing costs and time to market.”
Héctor Corte-Leon at NPL added: “Our first set of findings is very promising, and we are now expecting more positive outcomes over the next few months. Testing graphene-based electronics is key to demonstrating whether they can be used in harsh environments where, traditionally, their deployment has been limited.”