Separation of radiation induced and process induced lateral non-uniformities MOSFET

Fast measurements of channel current versus gate voltage (I-V) were performed on irradiated MOSFETs as a function of time and temperature after pulsed proton irradiation. Stretchout of the I-V curves due to lateral nonuniformities (LNUs) in the hole distribution in the oxide is shown to be experimentally separable from stretchout due to interface traps. The stretchout due to LNUs is then shown to consist of two experimentally separable components-one due to the random production of holes by the radiation, and one due to the random distribution of hole traps in the oxide. This suggests an entirely new approach for evaluating the quality of oxides in terms of the microscopic uniformity of the processing.>