Patent attributes
The present invention provides a technology which can suppress a variation in a value after a write operation to minimum so as to facilitate multi-bit operation in a semiconductor device such as a phase change memory. A semiconductor device includes: a memory cell having a storage element (phase change material) that stores information depending on a state change by temperature; an I/O circuit; and means which, when writing data, performs a set operation and an operation for writing desired data, measures a resistance value of the storage element by means of a verify operation, and when the resistance value is not within a target range, performs the set operation and the write operation again while changing a voltage to be applied to the storage element.
