Mechanism of Hot-Electron-Induced NMOSFET´s Degradation

A new experimental method for distinguishing the effects of trapped electrons in the gate oxide and generated interface traps in HE-Induced nMOSFET´s degradation has been proposed. Using this method, the causes of HE-induced gm degradation have been analyzed; gm degradation is caused by both trapped electrons and generated interface traps, and the generated interface-trap effect becomes more significant with increasing degradation. It was experimentally shown that critical hot electron energy for interface trap generation is present. The ratio of the critical energy ¿it to the mean free path of hot electrons in Si ¿ was obtained to be 5.7×106eV/cm. Using ¿=9.2nm[7], ¿it=5.2eV is derived.