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 a⁶⁰Co source. After successive irradiations and erasures amounting several tens of kGy[SiO₂], the devices exhibit a dispersion smaller than 2% in the responses.