N-type dopant out diffusion induced EEPROM failure

High fall out due to EEPROM failures were encountered during qualification of a device. All failures exhibit several random bits of EEPROM that cannot be erased. The root cause of the failure was due to out diffusion of phosphorus dopant under the floating gate. This paper describes the combination of analysis steps and tools, which include AFP, TEM and SCM that were used to identify the failure mechanism.