Smallest microchips yet folded from graphene

University of Sussex physicists have applied “nano-origami” to graphene to create a tiny object which behaves like a microchip. This could eventually lead to computers and phones running thousands of times faster than they do today.

 The researchers created the microchips from graphene and other 2D materials by creating kinks (defects) in its structure. The effect of these defects on the electronic and nano-mechanical properties had previously been poorly understood.

The researchers used atomic force microscopy and Raman mapping to identify the effects of various defects, such as standing collapsed wrinkles, folded wrinkles, and grain boundaries. They found that folding graphene alters its band structure: wrinkles result in minimal doping, while edges result in significant doping.

Folding certain distortions into graphene causes it to behave like a transistor: the building block of electronics. A strip of graphene folded in this manner causes it to behave like a microchip. However, the piece of graphene is approximately 100 times smaller than conventional microchips.

“Instead of having to add foreign materials into a device, we’ve shown we can create structures from graphene and other 2D materials simply by adding deliberate kinks into the structure,” said Dr Manoj Tripathi, who led the study. “By making this sort of corrugation we can create a smart electronic component like a transistor or a logic gate.”

The technique could allow for the continuation of Moore’s law (which states the number of transistors in an integrated circuit doubles approximately every two years). Academics and industry figures have cautioned for many years that Moore’s law may no longer be applicable as feature sizes approach physical limits for silicon chips.

Creating devices from graphene is one of several possible alternatives to conventional silicon electronics which could be utilised to preserve Moore’s law. This study marks the first time a microchip has been created from folded graphene.

Professor Alan Dalton said: “We’re mechanically creating kinks in a layer of graphene. It’s a bit like nano-origami. Using these nanomaterials will make our computer chips smaller and faster. It is absolutely critical that this happens as computer manufacturers are now at the limit of what they can do with traditional semiconducting technology. Ultimately, this will make our computers and phones thousands of times faster in the future.”

“This kind of technology – ‘straintronics’ using nanomaterials as opposed to electronics – allows space for more chips inside any device. Everything we want to do with computers, to speed them up, can be done by crinkling graphene like this.”

The development could also lead to more sustainable technology; no additional materials need to be added and the process is carried out at room temperature, requiring less energy to create the devices.