Electrically Erasable Metal–Oxide–Semiconductor Dosimeters

Metal-oxide-semiconductor (MOS) dosimetry including the reset of the sensor device for its reuse (reutilization) is described. The method consists in restoring the shifted threshold voltage after irradiation to a predefined value by the injection of a Fowler-Nordheim tunnel current. The amount of interface states per unit area is initially saturated in order to ensure repeatability. The method was tested on 70 nm pMOSFETs exposed to a ⁶⁰Co source. After successive irradiations and erasures amounting several tens of kGy[SiO₂], the devices exhibit a dispersion smaller than 2% in the responses.