In a nonvolatile memory cell having a trap layer, programming or erasing is made in a sequence of first charge injection with a given wait time being secured and second charge injection executed after the first charge injection. Surrounding charge that deteriorates the data retention characteristic is...http://www.google.com/patents/US20070047318?utm_source=gb-gplus-sharePatent US20070047318 - Nonvolatile semiconductor memory device and programming or erasing method therefor
