Extraction of coupling ratios for Fowler-Nordheim programming conditions

An analysis of extinction methodologies for the coupling ratios in non-volatile memories using numerical simulation is presented. The floating gate voltage of a non-volatile memory (NVM) cell cannot be accessed directly from measurements but can he derived using numerical simulation techniques. In this paper, various coupling ratio methodologies from literature are investigated using numerical simulation techniques and guidelines on improving the application of those methods to NVM cells are outlined. Measurements are performed which validate the increased accuracy of the methods and some of the improved methodologies are recommended for coupling ratio extraction in the Fowler Nordheim regime. This work demonstrates the role of numerical simulation in supplementing the electrical characterisation of NVM cells. (C) 2001 Elsevier Science Ltd, All rights reserved.