Two-step source side implant for improving source resistance and short channel effect in deep sub-0.18mum flash memory technology

摘要

Methods of forming flash memory EEPROM devices having lightly doped source region near the critical gate region and a heavily doped source region away from the critical gate region. In a first embodiment a first source mask is formed exposing source regions and portions of the gates and implanting n dopant ions, replacing the first source mask with a second source mask that exposes a portion of the source regions and implanting n<+> dopant ions. In a second embodiment a source mask is formed exposing a portion of the source regions and implanting n<+> dopant ions.