Abstract: The present disclosure is related to non-volatile memory devices comprising a reversible resistivity-switching layer used for storing data. The resistivity of this layer can be varied between at least two stable resistivity states such that at least one bit can be stored therein. In particular this resistivity-switching layer is a metal oxide or a metal nitride. A resistivity-switching non-volatile memory element includes a resistivity-switching metal-oxide layer sandwiched between a top electrode and a bottom electrode. The resistivity-switching metal-oxide layer has a gradient of oxygen over its thickness. The gradient is formed in a thermal oxidation step. Set and reset voltages can be tuned by using different oxygen gradients.

Abstract: The present disclosure is related to non-volatile memory devices comprising a reversible resistivity-switching layer used for storing data. The resistivity of this layer can be varied between at least two stable resistivity states such that at least one bit can be stored therein. In particular this resistivity-switching layer is a metal oxide or a metal nitride. A resistivity-switching non-volatile memory element includes a resistivity-switching metal-oxide layer sandwiched between a top electrode and a bottom electrode. The resistivity-switching metal-oxide layer has a gradient of oxygen over its thickness. The gradient is formed in a thermal oxidation step. Set and reset voltages can be tuned by using different oxygen gradients.