Creation and thermal annealing of interface states induced by uniform or localized injection in 2.3nm thick oxides.

To study the creation of interface states in 2.3 mn thin gate oxide in Metal-Oxide-Semiconductor transistors, direct or Fowler-Nordheim tunnel current and hot carrier stresses were performed. It is shown that for the considered stresses, the created interface state density follows a power law with both the injected charge and the stress time. After hot carrier stresses, more interface states can be created than after direct or Fowler-Nordheim stresses. In the range of measurements presented in this paper, the device breakdown observed after direct or Fowler-Nordheim stresses was not observed after hot carrier stresses. In the other hand, hot carrier stress was shown to be critical for the transistor characteristics. The thermal annealing of the created interface states, for different stresses, was studied showing a faster annealing of the defects after a slight stress than after a strong one. (C) 2001 Elsevier Science Ltd. All rights reserved.