Thin-film memristor using an amorphous metal-oxide semiconductor with a gradient composition of conducting components

A thin-film memristor using an amorphous metal-oxide semiconductor (AOS) with a gradient composition of conducting components has been developed, which is another way to achieve memristive properties. The advantages are that conductivity distribution is already obtained as fabricated without forming operation, and an analog characteristic is obtained by optimizing the component composition in AOS. As the binary characteristic, the set operation induces the transition from a low conductance state (LCS) to a high conductance state (HCS), whereas the reset operation does vice-versa. The switching ratio (SR) is high, 448. As the analog characteristic, the SR becomes greater rapidly as the Vset increases, namely, the dynamic range is outstanding.