Patent ID: 8619460

Claim:
A nonvolatile memory device comprising: a nonvolatile memory element including: a first electrode; a second electrode; and a variable resistance layer having a resistance state which reversibly changes between a high resistance state and a low resistance state in which a resistance value of said variable resistance layer is smaller than the resistance value in the high resistance state, based on electrical signals having different polarities which are given between said first electrode and said second electrode, said variable resistance layer being interposed between said first electrode and said second electrode; and a control circuit for applying a voltage having a first polarity between said first electrode and said second electrode to change a resistance state of said variable resistance layer from the low resistance state to the high resistance state, and applying a voltage having a second polarity opposite to the first polarity between said first electrode and said second electrode to change the resistance state of said variable resistance layer from the high resistance state to the low resistance state, wherein said control circuit: determines whether the resistance value of said variable resistance layer in the high resistance state is equal to or greater than a first threshold value; applies a first voltage having the second polarity between said first electrode and said second electrode if the resistance value of said variable resistance layer in the high resistance state is smaller than the first threshold value, to change the resistance state of said variable resistance layer from the high resistance state to the low resistance state; and applies a second voltage, which has the second polarity and an absolute value of which is smaller than an absolute value of the first voltage, between said first electrode and said second electrode if the resistance value of said variable resistance layer in the high resistance state is equal to or greater than the first threshold value, to change the resistance state of said variable resistance layer from the high resistance state to the low resistance state.