Electron barrier height change and its influence on EEPROM cells

The effect of floating polysilicon doping on electron injection barrier height and therefore the PROGRAM/ERASE window of an electrically erasable programmable ROM (EEPROM) cell has been studied. The introduction of dopant and the concentration of electrically active sites at the floating-gate polysilicon/tunnel oxide interface influence the electron injection barrier height during cell ERASE operation. The electron injection barrier increases up to 250 meV upon degenerate doping of the floating-gate polysilicon electrode as measured by dark current-voltage characteristics. The application of these observations in this study is in the design and scaling of EEPROM cells.<
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