Tyndall’s Radiation Sensing Field Effect Transistors (RADFETs) have originally been developed under European Space Agency’s sponsorship for radiation dose monitoring in space. The need to accurately measure ionising radiation doses is not limited to space exploration, but also exists in clinical environments (radiotherapy and radiology), homeland security domain (e.g. for first responders), nuclear facilities, high energy physics laboratories. All these applications require simple, cost-effective device which can accurately measure radiation doses of interest. Tyndall’s RADFET technology provides the solution.
RADFET is a MOS transistor optimised for radiation sensitivity. RADFET chip is a cube with a side of 0.5mm. Ionising radiation induces charge in the RADFET, which changes one of the basic transistor’s parameters – threshold voltage. Threshold voltage can easily be measured by passing a specified current through the RADFET and measuring a DC voltage at the device output. That DC voltage is indicative of the absorbed radiation dose.
Currently commercially available RADFETs from Tyndall cover a dose range of 1 cGy to > 1000 Gy. Novel patented devices with the minimum detectable dose of between 0.1–1 mGy and below are under development.
Tyndall National Institute
Dr. Aleksandar Jaksic