Stallings Katie, Smith Jeremy, Chen Yao, Zeng Li, Wang Binghao, Di Carlo Gabriele, Bedzyk Michael J, Facchetti Antonio, Marks Tobin J
Department of Chemistry and Materials Research Center, Northwestern University, Evanston, Illinois 60208, United States.
Applied Physics Program and the Materials Research Center, Northwestern University, Evanston, Illinois 60208, United States.
ACS Appl Mater Interfaces. 2021 Apr 7;13(13):15399-15408. doi: 10.1021/acsami.1c00249. Epub 2021 Mar 29.
Metal oxide semiconductors, such as amorphous indium gallium zinc oxide (a-IGZO), have made impressive strides as alternatives to amorphous silicon for electronics applications. However, to achieve the full potential of these semiconductors, compatible unconventional gate dielectric materials must also be developed. To this end, solution-processable self-assembled nanodielectrics (SANDs) composed of structurally well-defined and durable nanoscopic alternating organic (e.g., stilbazolium) and inorganic oxide (e.g., ZrO and HfO) layers offer impressive capacitances and low processing temperatures ( ≤ 200 °C). While SANDs have been paired with diverse semiconductors and have yielded excellent device metrics, they have never been implemented in the most technologically relevant top-gate thin-film transistor (TFT) architecture. Here, we combine solution-processed a-IGZO with solution-processed four-layer Hf-SAND to fabricate top-gate TFTs, which exhibit impressive electron mobilities (μ = 19.4 cm V s) and low threshold voltages ( = 0.83 V), subthreshold slopes (SS = 293 mV/dec), and gate leakage currents (10 A) as well as high bias stress stability.
金属氧化物半导体，如非晶铟镓锌氧化物（a-IGZO），作为非晶硅在电子应用中的替代品已取得了令人瞩目的进展。然而，要充分发挥这些半导体的潜力，还必须开发与之兼容的非常规栅极介电材料。为此，由结构明确且耐用的纳米级交替有机（如二苯乙烯基联吡啶）和无机氧化物（如ZrO和HfO）层组成的可溶液加工的自组装纳米电介质（SANDs）具有令人印象深刻的电容和较低的加工温度（≤200°C）。虽然SANDs已与多种半导体配对并产生了优异的器件指标，但它们从未在技术上最相关的顶栅薄膜晶体管（TFT）架构中得到应用。在此，我们将溶液加工的a-IGZO与溶液加工的四层Hf-SAND相结合，制造出顶栅TFT，其表现出令人印象深刻的电子迁移率（μ = 19.4 cm² V⁻¹ s⁻¹）、低阈值电压（Vth = 0.83 V）、亚阈值斜率（SS = 293 mV/dec）和栅极漏电流（10⁻¹² A）以及高偏置应力稳定性。
