Indium tin oxide (ITO) is a transparent conductor used in applications such as touch screens, smart windows and displays. A key limitation of ITO is its brittle nature, which prohibits its use in flexible electronics. The commercial deposition of high-quality ITO also currently relies on a costly vacuum manufacturing approach. Here we report the centimetre-scale synthesis of flexible two-dimensional ITO using a low-temperature liquid metal printing technique. The approach can directly deposit monolayer or bilayer ITO onto desired substrates, with the resulting bilayer samples offering a transparency above 99.3% and a sheet resistance as low as 5.4 kΩ □−1. We also show that the bilayer ITO features a stratified structure with a pronounced van der Waals spacing. To illustrate the capabilities of the technique, we develop a capacitive touch screen using centimetre-sized monolayer ITO sheets.
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We acknowledge technical support and instrumentation access provided by the RMIT Microscopy and Microanalysis Facility (RMMF) and MicroNano Research Facility (MNRF) at RMIT University. T.D. acknowledges funding received through the ARC DECRA scheme (DE190100100). We also acknowledge financial support received from the ARC Centre of Excellence FLEET (CE170100039). D.E. acknowledges the Scientia Fellowship scheme at the University of New South Wales. N.S. and A.Z. acknowledge funding from the Australian Government Research Training Program Scholarship scheme. S.P.R. is supported by the ARC (CE170100026). This work was also supported by computational resources provided by the Australian Government through the National Computational Infrastructure National Facility and the Pawsey Supercomputer Centre. This work was performed in part at the Melbourne Centre for Nanofabrication (MCN) in the Victorian Node of the Australian National Fabrication Facility (ANFF).
The authors declare no competing interests.
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Datta, R.S., Syed, N., Zavabeti, A. et al. Flexible two-dimensional indium tin oxide fabricated using a liquid metal printing technique. Nat Electron 3, 51–58 (2020). https://doi.org/10.1038/s41928-019-0353-8
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