Memristor’s present resistance electric charge

Memristor’s present resistance depends on how much electric charge has flowed through it in the past

1. Memristor’s present resistance depends on: how much electric charge has flowed through it in the past. flow direction of the electric charge Memristor’s basic operation A common analogy for a memristor is a pipe carrying water

2. More importantly, the memristor retains its most recent resistance when the power goes off. Therefore, the memristor holds the non-volatility property . Memristor= Mem ory R es istor

3. The first memristor device was found in 2008 by Stanley Williams et al . at HP laboratories The missing memristor found An array of 17 purpose-built titanium dioxide memristors built at HP Labs, imaged by an atomic force microscope. The wires are about 50  nm wide.

4. A thin film of titanium dioxide of width 3~30nm. Sandwiched between two platinum electrodes (contacts). The thin film is divided into two layers: doped layer and undoped layer. The undoped layer is a pure which is insulator material. The other layer of the is doped with oxygen vacancies, which are positively charged ions. This process makes the layer a highly conductive material.   The HP memristor structure * Oxygen vacancies

5. THE CROSSBAR ARCHITECTURE: The crossbar architecture is a fully connected mesh of perpendicular wires. Any two crossing wires are connected by a switch. To close the switch, a positive voltage is applied across the two wires to be connected. To open the switch, the voltage is reversed . THE SWITCH: A switch is a 40-nanometer cube of titanium dioxide ( ) in two layers: The lower layer has a perfect 2:1 oxygen-to-titanium ratio, making it an insulator. By contrast, the upper TiO2 layer is missing 0.5 percent of its oxygen ( ), so x is about 0.05. The vacancies make the material metallic and conductive.   The HP memristor structure