Nanowires have excellent physical and chemical properties and are suitable for manufacturing flexible electronic products. Therefore, in order to improve the performance of devices, it is important to develop nanowire technology that can be transferred and arranged neatly.
A research team at the Korea Advanced Institute of Science and Technology (KAIST) has successfully developed nanowire transfer technology that is expected to surpass existing chemical reaction-based nanowire manufacturing technologies. So far, we know that the existing nanowire manufacturing technology has the disadvantages of poor applicability, low productivity, and other poor overall performance.
Photographs of fully aligned wafer sizes and ultra-long Au nanowire arrays made on a flexible substrate.
As one of the most famous nanomaterials, nanowires have the advantages of small size and light weight. Therefore, nanowire transfer technology has attracted much attention because it can produce flexible nanodevices with high performance, extremely simplified and high throughput.
Traditional nanowire manufacturing methods usually have irregularities. This is because the traditional method is to mix chemically synthesized nanowires in a solution and randomly distribute the nanowires onto a flexible substrate. This will inevitably make the manufactured nanowires. Has irregularities.
As a result, many nanofabrication processes have emerged, one of which is a master-mode-based nanoarray. In this process, a highly ordered array of nanowires can be embedded on a substrate in a simple and efficient manner to transfer nanowires. . However, due to the complexity and time consuming of its chemical-based NW transfer mechanism, the application of this process is limited to certain materials. To successfully transfer nanowires, sufficient chemicals are needed to control the chemical interface adhesion capabilities between the master mold, the nanowires, and the flexible substrate.
Here, Professor Jun-Bo Yoon and his team from the School of Electrical Engineering propose a material-independent mechanical interlocking nanowire transfer (Mint) method that is fabricated in a very efficient manner on large flexible substrates Ultra-long and fully aligned nanowire arrays.
The specific process of this method is to sequentially form a nanolayer and a nanowire on a nanograting substrate, so that the nanolayer becomes the master mode of the transfer, and then the structure of the nanolayer is weakened by the dry etching process, and the nanolayer maintains the nanowire on the master mode. The ability is very weak, so when using flexible substrate materials, nanowires are easily transferred from the master mold to the substrate, a process that is like a piece of tape that uses adhesive to remove dust from the carpet.
This technology uses a common physical vapor deposition technology, which has the advantage of not relying on nanowire materials, which makes it easier to prepare nanowires on flexible substrates.
Using this technology, the team produced a wide variety of metal and metal oxide nanowires, including gold, platinum, and copper nanowires, which were perfectly aligned on a flexible substrate. They also experimentally confirmed that the manufactured nanowires can be successfully applied to flexible heaters and gas sensors, thereby creating stable and applicable devices in daily life.
Dr Seo, who led the research, said: "We have successfully integrated a variety of metal and semiconductor nanowires with excellent physical properties onto flexible substrates and applied them to manufacturing equipment. As a platform technology, the technology Will help develop high-performance and stable electronic equipment. "