Patent ID: 8437173
Filing Date: 2013-05-07
Classification: G11C,H01L

Abstract:
1. A nonvolatile memory element comprising: a first electrode and a second electrode that are formed above a semiconductor substrate; and a variable resistance layer located between said first electrode and said second electrode and having a resistance value that reversibly changes based on an electric signal applied between said first electrode and said second electrode, wherein said variable resistance layer comprises at least two layers including a first variable resistance layer and a second variable resistance layer, said first variable resistance layer has a first face connected to said first electrode, said first variable resistance layer has a second face connected to said second variable resistance layer, said first variable resistance layer comprises a first transition metal oxide, said second variable resistance layer comprises a second transition metal oxide and a third transition metal oxide, the second transition metal oxide has an oxygen deficiency higher than either an oxygen deficiency of the first transition metal oxide or an oxygen deficiency of the third transition metal oxide, the third transition metal oxide is in contact with at least part of the second face of said first variable resistance layer, and the second transition metal oxide is in contact with a remaining part of the second face of said first variable resistance layer.