3D spintronic microchip


SCIENTISTS from the University of Cambridge have created a new type of microchip which allows information to travel in three dimensions.

The research, authored by Dr Reinoud Lavrijsen from the Cavendish Laboratory of the University of Cambridge, was published in the journal Nature on 31 January, in a paper titled “Magnetic ratchet for three-dimensional spintronic memory and logic".

Currently, microchips pass digital information in a very limited way, either from left to right or front to back. A 3D microchip in the future would allow additional storage capacity on chips, since information will no longer be restricted to one layer, but instead can be spread across several layers.

For the research, the Cambridge scientists used a spintronic chip which exploits the electron's tiny magnetic moment or 'spin'.

They then used an experimental technique called sputtering to create the microchip, by layering cobalt, platinum and ruthenium atoms on a silicon chip. The cobalt and platinum atoms store the digital information in a similar way to how a hard disk drive stores data.

The ruthenium atoms act as messengers, communicating that information between neighbouring layers of cobalt and platinum. Each of the layers is only a few atoms thick.

To probe the data content of the different layers, the scientists used a laser technique called MOKE. When a magnetic was switched on, the MOKE signal indicated that the data was climbing layer by layer from the bottom of the chip to the top.

Traditionally, a series of electronic transistors would be used to move the data in a similar manner, but the researchers achieved the same effect by combining different basic elements.