Patent ID: 8867259

Claim:
A method of programming a variable resistance nonvolatile memory element, the method of programming reversibly changing, by applying a voltage pulse to the variable resistance nonvolatile memory element, a resistance state of the variable resistance nonvolatile memory element, wherein the variable resistance nonvolatile memory element includes: a first electrode; a second electrode; and an oxygen-deficient transition metal oxide layer provided between the first and second electrodes, the transition metal oxide layer includes: a first transition metal oxide layer that is in contact with the first electrode; and a second transition metal oxide layer that is in contact with the second electrode and has a degree of oxygen deficiency lower than a degree of oxygen deficiency of the first transition metal oxide layer, and after the variable resistance nonvolatile memory element is manufactured and an initial breakdown voltage pulse having a predetermined amplitude is applied between the first and second electrodes, the variable resistance nonvolatile memory element has characteristics of (i) changing to a low resistance state when a low resistance writing voltage pulse for providing a negative electric potential to the second electrode with respect to the first electrode is applied, and (ii) changing to a high resistance state when a high resistance writing voltage pulse for providing a positive electric potential to the second electrode with respect to the first electrode is applied, the high resistance state being higher in resistance value than the low resistance state, the method of programming comprising, in the case where the variable resistance nonvolatile memory element cannot change to the low resistance state and remains in the high resistance state when the low resistance writing voltage pulse is applied to the variable resistance nonvolatile memory element, applying a recovery voltage pulse to the variable resistance nonvolatile memory element at least once, the recovery voltage pulse including: a first recovery voltage pulse that has an amplitude greater than an amplitude of the high resistance writing voltage pulse and provides the positive electric potential to the second electrode with respect to the first electrode; and a second recovery voltage pulse that follows the first recovery voltage pulse and provides the negative electric potential to the second electrode with respect to the first electrode.