Analysis of Cycling Induced Interface Degradation in Si Nanocrystal Memory Devices

Abstract

This work has investigated the interface degradation of Si-nanocrystal memory devices under Fowler-Nordheim program/erase cycling. The evolution of the high-frequency capacitance-voltage curves pointed out that the mean density of interface traps had an unsymmetrical distribution around the surface intrinsic Fermi level (Eis) and the acceptor-type interface traps generated much faster than the donor-type ones during the cycling stress. It was further supported by the charge pumping measurement under several stress conditions. The energy distribution of the interface traps near Eis had a clear step-like shape with a higher density of acceptor-type interface traps. The results show that the generation of acceptor-type interface traps played a dominant role in the interface degradation.