• FinTech
  • Forex Trading
  • Sober living

28 septembre 2022

[Nanotechnology] – Discovery of new nanowire assembly process could enable more powerful computer chips

Accueil > Actualités > [Nanotechnology] – Discovery of new nanowire assembly process could enable more powerful computer chips
Flèche contenu

In a newly-published study (Small, “A Universal Pick-and-Place Assembly for Nanowires”), a team of researchers in Oxford University’s Department of Materials led by Harish Bhaskaran, Professor of Applied Nanomaterials, describe a breakthrough approach to pick up single nanowires from the growth substrate and place them on virtually any platform with sub-micron accuracy.

The innovative method uses novel tools, including ultra-thin filaments of polyethylene terephthalate (PET) with tapered nanoscale tips that are used to pick up individual nanowires. At this fine scale, adhesive van der Waals forces (tiny forces of attraction that occur between atoms and molecules) cause the nanowires to ‘jump’ into contact with the tips. The nanowires are then transferred to a transparent dome-shaped elastic stamp mounted on a glass slide. This stamp is then turned upside down and aligned with the device chip, with the nanowire then printed gently onto the surface.

Deposited nanowires showed strong adhesive qualities, remaining in place even when the device was immersed in liquid. The research team were also able to place nanowires on fragile substrates, such as ultra-thin 50 nanometre membranes, demonstrating the delicacy and versatility of the stamping technique.

In addition, the researchers used the method to build an optomechanical sensor (an instrument that uses laser light to measure vibrations) that was 20 times more sensitive than existing nanowire-based devices.
Nanowires, materials with diameters 1000 times smaller than a human hair and fascinating physical properties, could enable major advancements in many different fields, from energy harvesters and sensors, to information and quantum technologies. In particular, their minuscule size could allow the development of smaller transistors and miniaturised computer chips. A major obstacle, however, to realising the full potential of nanowires has been the inability to precisely position them within devices.

Most electronic device manufacturing techniques cannot tolerate the conditions needed to produce nanowires. Consequently, nanowires are usually grown on a separate substrate and then mechanically or chemically transferred to the device. In all existing nanowire transfer techniques, however, the nanowires are placed randomly onto the chip surface, which limits their application in commercial devices.

DPhil student Utku Emre Ali (Department of Materials), who developed the technique, said: ‘This new pick-and-place assembly process has enabled us to create first-of-its-kind devices in the nanowire realm. We believe that it will inexpensively advance nanowire research by allowing users to incorporate nanowires with existing on-chip platforms, be it electronic or photonic, unlocking physical properties that have not been attainable so far. Furthermore, this technique could be fully automated, making full-scale fabrication of high quality nanowire-integrated chips a real possibility.’

Découvrir
[Plasma] – Temperature of solar flares helps understand nature of solar plasma 14 novembre 2023

The Sun’s rotation produces changes in its magnetic field, which flips completely every 11 years or so, triggering a phase of intense activity.

Lire la suite
[Nanotechnology] – Spiral dislocation gives 3D topological photonics a robust edge 28 septembre 2022

Researchers from the University of Rostock and Technion Haifa have created the first three-dimensional topological insulator for light. A judiciously placed screw dislocation allows optical signals to wind around the surface of a synthetic lattice while keeping it protected from scattering.
Their discovery has recently been published in the journal Nature (“Photonic topological insulator induced by a dislocation in three dimensions”).

Lire la suite