Limitations on MOSFET dosimeter resolution imposed by 1/f noise

A sensitive microcomputer-controlled MOSFET-based dosimeter system has been constructed to examine the effects limiting the ability of MOSFET dosimeters to detect very small radiation doses. It is shown that the dose resolution of this system is limited by 1/f noise in the sensor MOSFET's themselves. Doses below 1 mGy (100 mrad) can be detected. Structural changes to the sensor MOSFET's that might provide further improvements in resolution through reduction of 1/f noise are discussed.