Researchers at Nagoya University in Japan have created a new technique to mass produce pure metal nanowires, which can be used in next-generation electronics. The method uses atomic diffusion and ion beam irradiation to grow aluminum nanowires from single crystals.
Mass production of nanowires has been challenging due to the difficulty of scaling while maintaining quality and purity. These tiny structures are made by transporting atoms, typically in a gas phase state, which is hard to achieve with metals.
The new technique involves using atomic diffusion in a solid phase state enhanced by ion beam irradiation to create aluminum nanowires from single crystals. The process begins by depositing a thin aluminum film on a substrate and then irradiating the crystal grains inside it with an ion beam. This causes changes in stress distribution, guiding atomic flow and supplying mass atomic feedstocks for growth.
When heat is applied, the atoms flow upward through the gradient, resulting in the mass growth of nanowires. The researchers were able to increase the density of aluminum nanowires from 2×10^5 per square cm to 18×10^5 per square cm.
The produced aluminum nanowires have unique features such as a large surface area, good mechanical properties derived from being made from single crystals, and resistance to natural oxidation. These nanocomponents are expected to be used in sensing devices and optoelectronics due to their potential applications in gas sensors, biomarkers, and optoelectronic components.
The researchers believe that this technique can be extended to other metals in principle, solving the urgent need for mass production methods in high-performance nanodevices. The study was published in Science.
Source: https://phys.org/news/2024-09-atomic-diffusion-technique-mass-production.html