Bake induced charge gain in NOR flash cells

  title={Bake induced charge gain in NOR flash cells},
  author={R. Fastow and K. Ahmed and S. Haddad and M. Randolph and C. Huster and P. Hom},
  journal={IEEE Electron Device Letters},
Charge gain, caused by localized defects in the tunnel oxide of floating gate devices, is one of the central reliability concerns of flash memory. In this work, we show that charge motion in the poly sidewall spacers of flash cells can also result in substantial charge gain, for nonoptimized processes. Data showing the time, temperature, and field dependencies of this charge gain mechanism are presented. It is shown that the threshold voltage shift caused by charge motion in the poly sidewall… 

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