Selective erase method for NOR-type flash memory used in e.g. computer, involves identifying memory cells having threshold voltage lower than desired erase threshold voltage, after performing erase operation on group of memory cells

摘要

An erase operation is performed on a group of memory cells, and one or more rows of memory cells having a threshold voltage lower than a desired erase threshold voltage, are identified. A further erase operation is performed on the memory cells excluding the identified row or rows of memory cells.