Carbon doping MOSFET substrate to suppress hit electron trapping

摘要

A MOSFET device having a near-micrometer or submicrometer channel length and designed to operated under conditions that cause generation of hot carriers is carbon doped in the silicon substrate at the gate oxide-silicon interface. The oxide-silicon interface can include hydrogen atoms. These atoms are mostly bonded to carbon atoms, more strongly than hydrogen bonds to silicon, so that hot carriers are less likely to dissociate the hydrogen atoms and form hot carrier trapping sites at the interface. Hot carrier aging is thus substantially reduced. This capability is particularly useful in submicrometer devices, avoiding need to reduce normal operating voltages.