Multi-level non-volatile resistive device with write-verify algorithm

A resistive memory device configurable to operate in volatile or non-volatile modes, comprising:

• a first electrode;
• a second electrode;
• and,
• an active switching bilayer formed of a first variable conductive layer and a second variable conductive layer ionically coupled together and electrically coupled between the first electrode and the second electrode, wherein
• in a volatile mode of operation the first variable conductive layer transfers ions into the second variable conductive layer to change electrical conductivity in response to at least one applied voltage sweep of a first polarity across the first electrode and the second electrode, and receives ions from the second variable conductive layer to change back electrical conductivity by at least one of naturally relaxing ions back and in response to at least one applied voltage sweep of a second polarity across the first electrode and the second electrode;
• and
• in a non-volatile mode of operation conductive filaments are formed in the bilayer to set a low resistance state (LRS) in response to application of a first voltage across the first and second electrodes, and the conductive filaments are ruptured to set a high resistance state (HRS) in response to a second voltage in the same or opposite in polarity to the first voltage.