Jannat Azmira, Syed Nitu, Xu Kai, Rahman Md Ataur, Talukder Md Mehdi Masud, Messalea Kibret A, Mohiuddin Md, Datta Robi S, Khan Muhammad Waqas, Alkathiri Turki, Murdoch Billy J, Reza Syed Zahin, Li Jing, Daeneke Torben, Zavabeti Ali, Ou Jian Zhen
School of Engineering, RMIT University, Melbourne, Victoria 3000, Australia.
College of Science, Engineering and Health, RMIT University, Melbourne, Victoria 3000, Australia.
ACS Nano. 2021 Mar 23;15(3):4045-4053. doi: 10.1021/acsnano.0c06791. Epub 2021 Jan 26.
Ultrathin transparent conductive oxides (TCOs) are emerging candidates for next-generation transparent electronics. Indium oxide (InO) incorporated with post-transition-metal ions (, Sn) has been widely studied due to their excellent optical transparency and electrical conductivity. However, their electron transport properties are deteriorated at the ultrathin two-dimensional (2D) morphology compared to that of intrinsic InO. Here, we explore the domain of transition-metal dopants in ultrathin InO with the thicknesses down to the single-unit-cell limit, which is realized in a large area using a low-temperature liquid metal printing technique. Zn dopant is selected as a representative to incorporate into the InO rhombohedral crystal framework, which results in the gradual transition of the host to quasimetallic. While the optical transmittance is maintained above 98%, an electron field-effect mobility of up to 87 cm V s and a considerable sub-kΩ cm ranged electrical conductivity are achieved when the Zn doping level is optimized, which are in a combination significantly improved compared to those of reported ultrathin TCOs. This work presents various opportunities for developing high-performance flexible transparent electronics based on emerging ultrathin TCO candidates.
超薄透明导电氧化物（TCO）是下一代透明电子器件的新兴候选材料。与后过渡金属离子（如锡）结合的氧化铟（InO）因其优异的光学透明度和导电性而受到广泛研究。然而，与本征InO相比，它们在超薄二维（2D）形态下的电子传输性能会变差。在此，我们探索了厚度低至单胞极限的超薄InO中过渡金属掺杂剂的领域，这是通过低温液态金属印刷技术在大面积上实现的。选择锌掺杂剂作为代表性物质掺入InO菱面体晶体框架中，这导致主体逐渐向准金属转变。当锌掺杂水平优化时，虽然光学透过率保持在98%以上，但可实现高达87 cm² V⁻¹ s⁻¹的电子场效应迁移率和相当可观的亚千欧厘米范围的电导率，与已报道的超薄TCO相比，这些性能的组合得到了显著改善。这项工作为基于新兴超薄TCO候选材料开发高性能柔性透明电子器件提供了各种机会。
