Patent ID: 8264865

Claim:
A nonvolatile memory element comprising: a first electrode; a second electrode; and a resistance variable layer which is interposed between the first electrode and the second electrode and is configured to switch a resistance value reversibly in response to electric signals applied between the electrodes; the nonvolatile memory element being configured to reversibly switch a resistance value between the first electrode and the second electrode in response to electric signals of different polarities which are applied between the first electrode and the second electrode; wherein the resistance variable layer has a multi-layer structure in which a second oxygen-deficient hafnium oxide layer being electrically conductive and having a composition expressed as HfO x (0.9≦x≦1.6), and a first oxygen-deficient hafnium oxide layer being electrically conductive and having a composition expressed as HfO y (1.8<y<2.0)are stacked together.