ANNEALING CHARACTERISTICS OF HOT CARRIER INDUCED DAMAGE IN N-CHANNEL MOSFETS

The recovery process of hot carrier induced degraded device parameters in n-channel MOSFETs has been analysed by both isothermal and isochronal annealing. A wide distribution of activation energies of hot carrier induced damage, with a peak at around 0.9 eV is observed. It can be seen that isochronal annealing has advantages over isothermal annealing in recovering the degraded device characteristics in comparatively less time. Bias annealing of the device reveals that initially the annealing of trapped oxide charges increases the interface state density, after reaching the peak value interface states anneal as a logarithmic function of time. The energy distribution of hot carrier induced interface states is similar to radiation induced interface states after a few hours of annealing at room temperature.