A research team from Northwestern Engineering, led by Prof. Pedram Khalili developed highly efficiency nanoscale perpendicular MRAM (pMTJ) devices that use sub-volt switching. The researcher say that this new technology can allow scaling MRAM to very high densities.
The new devices are referred to as voltage-controlled MRAM (VCM), that does not rely on current like regular MRAM devices. Most VCM devices need high switching voltage (at least 2 volts), but by using a new material structure with significantly higher sensitivity of the magnetic properties to voltage, the researchers were able to operate at less than one volt.
The new material structure also possesses all other important attributes for a practical memory device, including a high on/off ratio — also called tunnel magnetoresistance (TMR) ratio — and the ability to withstand high processing temperatures. This device is also smallest VCM device reported to date (a diameter of 30 nanometers).