Varadis RADFET VT02

400nm RADFET in Eight Lead Ceramic Side Braze Package

For doses between 1 cGy (1 rad) and 1 kGy (100 krad)

RADFET is a discrete p-channel MOSFET optimized for radiation sensitivity. RADFETs are sensitive to ionizing radiation: gamma rays, X-rays, and protons.

The VT02 is used by organisations such as the European Space Agency and a number of other space agencies across the globe.    The VT02 is hermetically sealed and slightly larger than the plastic version.

The critical region of the RADFET is its gate oxide. Through generation and trapping of radiation-induced charges in the gate oxide, radiation exposure changes the output voltage of the RADFET and this change is related to the radiation dose. The RADFET response is non-linear and a pre-recorded calibration curve is used to read the dose. The read-out is done by forcing a DC current (in the range of 10s of μA) into the device and measuring the DC voltage (in the range of 0.5 to ~8 Volts).