Knowledge Center
Knowledge Center

Resistive RAM (ReRAM/RRAM)

Memory utilizing resistive hysteresis


Resistive RAM (ReRAM, also known as RRAM) works by changing the resistance of materials. An electric current is applied to a material, changing the resistance of that material. The resistance state can then be measured. This principle is called ‘memrister’ and relies on the principle of hysteresis.

Its invention is attributed to Hewlett Packard Senior Fellow R. Stanley Williams at HP Labs, who used a bi-level titanium dioxide thin-film to store the resistance. However, the memristor was first postulated in a seminal 1971 paper in the IEEE Transactions on Circuit Theory by professor Leon Chua at the University of California. JPL published an article in 1990 titled “Solid-state thin-film memistor for electronic neural networks.” This paper reports on a tungsten-oxide-based, nonvolatile, electrically reprogrammable, variable resistance device as an analog synaptic memory connection for electronic neural networks.

Work is still ongoing to find appropriate materials and measuring the resistance state of the cells. This technology promises to be smaller than flash and to have overcome endurance issues. It also has much faster write speeds, comparable even to DRAM.

Memristor Networks

Advances in Non-volatile Memory and Storage Technology (Woodhead Publishing Series in Electronic and Optical Materials)

Related Technologies