Chakraborty Rajarshi, Pramanik Subarna, Pal Nila, Pandey Utkarsh, Suman Swati, Swaminathan Parasuraman, Pal Bhola Nath
School of Materials Science and Technology, Indian Institute of Technology (Banaras Hindu University), Varanasi 221005, India.
Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036, India.
ACS Appl Mater Interfaces. 2024 Sep 11;16(36):47820-47831. doi: 10.1021/acsami.4c07345. Epub 2024 Sep 1.
The exploration of synaptic plasticity in metal-oxide-based ferroelectric thin-film transistors has been limited. As a perovskite ferroelectric material, LiNbO is widely studied; but its potential use as a neuromorphic device, like synaptic transistors, has not been realized. In this study, a solution-processed ferroelectric thin-film transistor (FeTFT) with an alternating layer of LiNbO and LiAlO as a gate dielectric has been fabricated. This configuration reduces the depolarization field by leveraging the large ionic polarization of Li ions in the LiAlO layer, while the wide bandgap helps mitigate the leakage current. FeTFT exhibits impressive transistor performance, including a saturation mobility of 0.478 cmV s, an on/off ratio of 3.08 × 10, and a low trap-state density of 1.3 × 10 cm. Moreover, the device demonstrates good memory retention, retaining information for nearly 1 day. It successfully emulates synaptic plasticity, specifically short-term plasticity and long-term plasticity. Besides, a 94% training accuracy has been achieved through artificial neural network simulation. Notably, the FeTFT consumes minimal power, with energy consumption of approximately 3.09 nJ per synaptic event, which is remarkably low compared to other reported solution-processed FeTFT devices.
基于金属氧化物的铁电薄膜晶体管中突触可塑性的探索一直很有限。作为一种钙钛矿铁电材料,铌酸锂(LiNbO)得到了广泛研究;但其作为神经形态器件(如突触晶体管)的潜在用途尚未实现。在本研究中,制备了一种以LiNbO和LiAlO交替层作为栅极电介质的溶液法制备的铁电薄膜晶体管(FeTFT)。这种结构通过利用LiAlO层中锂离子的大离子极化来降低去极化场,而宽带隙有助于减轻漏电流。FeTFT表现出令人印象深刻的晶体管性能,包括0.478 cm²V⁻¹s⁻¹的饱和迁移率、3.08×10³的开/关比和1.3×10¹² cm⁻²的低陷阱态密度。此外,该器件表现出良好的记忆保持能力,能够将信息保留近1天。它成功地模拟了突触可塑性,特别是短期可塑性和长期可塑性。此外,通过人工神经网络模拟实现了94%的训练准确率。值得注意的是,FeTFT功耗极低,每次突触事件的能量消耗约为3.09 nJ,与其他报道的溶液法制备的FeTFT器件相比,这一数值非常低。