Nanoscale printers may bypass factories

Solvent containing nanoparticles (yellow dots) flows out of a capillary and forms controllably ultra-small droplets. The solvent evaporates rapidly from the droplets, leaving a structure made of accumulated nanoparticles in its wake (credit: Patrick Galliker/ETH Zurich)

ETH-Zurich researchers have developed an economic, fast and reproducible method for printing micro- and nanoscale (<100 nm) structures in a manner similar to an ink-jet printer printing art.

The trick: ultrafine particles are transferred onto a surface from a capillary with the aid of an electrical field. Depending on how long material accumulates at the same spot, the structure can be a dot or nano-tower, or even an arch.

Surfaces modified with nano-structures can absorb, concentrate and transmit light instead of reflecting it.

Applications

• Increased efficiency of thin-film solar cells by capturing the light and channeling it directly towards the active layer, for instance, instead of reflectng part of the light and letting another part escape unused.
• Camouflage suits
• New kinds of faster, more selective and highly sensitive detectors and sensors might be feasible.
• Special light microscopes in which light nanoantennas trigger fluorescence, enabling individual molecules to be observed.
• Wherever material needs to be applied on a nanoscale in a targeted fashion — a CPU printed on the spot, for example.

Using the new method, researchers can print dots, small towers, lines and other structures at the nanoscale (SEM image) (credit: Patrick Galliker / ETH Zurich)

Advantages

• Structures can be applied to different surfaces in a quick and reproducible manner.
• Fast because the printer can be programmed in such a way that material is applied precisely where it is needed.
• Removal and waste of excess material no longer required.
• Less expensive — no large-scale facilities, high calssification cleanrooms, exceedingly high temperatures or special pressure ratios, and laborious and time-consuming vacuum steps.
• Throughput and size of the printed surfaces may be increased considerably during industrial production.
• Prototyping at the smallest scale could be performed fast and affordably.

The researchers next plan to develop a print head containing several individually addressable capillaries to increase throughput and enable stacking layers of different materials.

---

Original Page: http://www.kurzweilai.net/nanoscale-printers-may-bypass-factories

-Michael