Slow and fast states induced by hot electrons at Si-SiO2 interface

Abstract

The kinetics of formation of both fast and slow states at the Si-SiO 2 interface during avalanche injection is carefully examined on Al gate, wet oxide metal-oxide-silicon capacitors. They are both found to approach exponentially a saturation value. The annealing behavior of fast and slow states is examined by means of isochronal heat treatments. They can be annihilated at temperatures lower than 600°K with similar activation energies. Correlations between slow and fast states are discussed. The instability of flatband voltage after avalanche injection due to the presence of slow states is characterized at various temperatures and electric fields. A process involving thermal activated hopping (Continuous Time Random Walk Model) among the slow states may be invoked in order to explain the experimental data.