IBM scientists have created a 3D map of the earth so small that 1,000 of them could fit on a single grain of salt.
They accomplished this through a new, breakthrough technique that uses a tiny, silicon tip with a sharp apex — 100,000 times smaller than a sharpened pencil point — to create patterns and structures as small as 15 nanometre at greatly reduced cost and complexity.
A nanometre is a billionth of a metre. This patterning technique opens new prospects for developing nanosized objects in fields such as electronics, future chip technology, medicine, life sciences, and optoelectronics.
To demonstrate the technique's unique capability, the team created several 3D and 2D patterns, using different materials for each one.
A 25-nanometre-high 3D replica of the Matterhorn, a famous Alpine mountain that soars 4,478 metres (14,692 feet) high, was created in molecular glass, representing a scale of 1:5 billion.
Complete 3D map of the world measuring only 22 by 11 micrometre was “written” on a polymer.
At this size, 1,000 world maps could fit on a grain of salt. A kilometre of altitude corresponds to roughly eight nanometre.
It is composed of 500,000 pixels, each measuring 20 square nanometre, and was created in only 2 minutes and 23 seconds.
A 2D nano-sized IBM logo was etched 400-nm-deep into silicon, demonstrating the viability of the technique for typical nanofabrication applications.
The core component of the new technique is a tiny, very sharp silicon tip measuring 500 nanometre in length and only a few nanometres at its apex.
“Advances in nanotechnology are intimately linked to the existence of high-quality methods and tools for producing nanoscale patterns and objects on surfaces,” explains physicist Armin Knoll of IBM Research, Zurich.
“With its broad functionality and unique 3D patterning capability, this nanotip-based patterning methodology is a powerful tool for generating very small structures,” said Knoll, according to an IBM release.
The tip, similar to the kind used in atomic force microscopes, is attached to a bendable cantilever that controllably scans the surface of the substrate material with the accuracy of one nanometre.
By applying heat and force, the nano-sized tip can remove substrate material based on predefined patterns, thus operating like a “nanomilling” machine with ultra-high precision.