Kulkarni Mohit Rameshchandra, John Rohit Abraham, Tiwari Nidhi, Nirmal Amoolya, Ng Si En, Nguyen Anh Chien, Mathews Nripan
School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
Energy Research Institute @ NTU (ERI@N), Nanyang Technological University, Singapore, 637553, Singapore.
Small. 2019 Jul;15(27):e1901457. doi: 10.1002/smll.201901457. Epub 2019 May 23.
Despite extensive research, large-scale realization of metal-oxide electronics is still impeded by high-temperature fabrication, incompatible with flexible substrates. Ideally, an athermal treatment modifying the electronic structure of amorphous metal oxide semiconductors (AMOS) to generate sufficient carrier concentration would help mitigate such high-temperature requirements, enabling realization of high-performance electronics on flexible substrates. Here, a novel field-driven athermal activation of AMOS channels is demonstrated via an electrolyte-gating approach. Facilitating migration of charged oxygen species across the semiconductor-dielectric interface, this approach modulates the local electronic structure of the channel, generating sufficient carriers for charge transport and activating oxygen-compensated thin films. The thin-film transistors (TFTs) investigated here depict an enhancement of linear mobility from 51 to 105.25 cm V s (ionic-gated) and from 8.09 to 14.49 cm V s (back-gated), by creating additional oxygen vacancies. The accompanying stochiometric transformations, monitored via spectroscopic measurements (X-ray photoelectron spectroscopy) corroborate the detailed electrical (TFT, current evolution) parameter analyses, providing critical insights into the underlying oxygen-vacancy generation mechanism and clearly demonstrating field-induced activation as a promising alternative to conventional high-temperature annealing strategies. Facilitating on-demand active programing of the operation modes of transistors (enhancement vs depletion), this technique paves way for facile fabrication of logic circuits and neuromorphic transistors for bioinspired computing.
尽管进行了广泛的研究，但金属氧化物电子器件的大规模实现仍受到高温制造的阻碍，因为高温制造与柔性基板不兼容。理想情况下，一种能改变非晶态金属氧化物半导体（AMOS）电子结构以产生足够载流子浓度的无热处理方法，将有助于降低此类高温要求，从而在柔性基板上实现高性能电子器件。在此，通过电解质栅控方法展示了一种新型的场驱动AMOS沟道无热激活。这种方法促进带电氧物种在半导体 - 电介质界面的迁移，调节沟道的局部电子结构，产生足够的载流子用于电荷传输并激活氧补偿薄膜。此处研究的薄膜晶体管（TFT）通过产生额外的氧空位，使线性迁移率从51提高到105.25 cm² V⁻¹ s⁻¹（离子栅控）以及从8.09提高到14.49 cm² V⁻¹ s⁻¹（背栅控）。通过光谱测量（X射线光电子能谱）监测到的伴随化学计量变化，证实了详细的电学（TFT、电流演变）参数分析，为潜在的氧空位产生机制提供了关键见解，并清楚地表明场诱导激活是传统高温退火策略的一种有前景的替代方法。这种技术有助于对晶体管的工作模式进行按需主动编程（增强型与耗尽型），为简便制造用于生物启发计算的逻辑电路和神经形态晶体管铺平了道路。
