A method for in-factory testing of flash EEPROM devices

摘要

A method for in-factory testing of a flash EEPROM device comprising a matrix of memory cells (1) and redundancy memory cells (1') for functionally substituting defective memory cells (1''), comprises the steps of: programming all the memory cells (1) of the memory device; submitting all the memory cells (1) of the memory device to a preliminary electrical erasure for a time much shorter than an average erasing time of the memory cells (1); reading the information stored in all the memory cells (1) of the memory device; memorizing the addresses of defective memory cells (1'') which have been read as erased memory cell; storing the addresses of the defective memory cells (1'') in redundancy registers (15,20) associated to redundancy memory cells (1') which must substitute the defective memory cells (1'').