Luo Yongjian, Wang Zhen, Chen Yu, Qin Minghui, Fan Zhen, Zeng Min, Zhou Guofu, Lu Xubing, Gao Xingsen, Chen Deyang, Liu Jun-Ming
Guangdong Provincial Key Laboratory of Optical Information Materials and Technology and Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China.
Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China.
ACS Appl Mater Interfaces. 2023 Apr 5;15(13):16902-16909. doi: 10.1021/acsami.3c01866. Epub 2023 Mar 26.
Ferroelectrics with negative capacitance effects can amplify the gate voltage in field-effect transistors to achieve low power operation beyond the limits of Boltzmann's Tyranny. The reduction of power consumption depends on the capacitance matching between the ferroelectric layer and gate dielectrics, which can be well controlled by adjusting the negative capacitance effect in ferroelectrics. However, it is a great challenge to experimentally tune the negative capacitance effect. Here, the observation of the tunable negative capacitance effect in ferroelectric KNbO through strain engineering is demonstrated. The magnitude of the voltage reduction and negative slope in polarization-electric field (-) curves as the symbol of negative capacitance effects can be controlled by imposing various epitaxial strains. The adjustment of the negative curvature region in the polarization-energy landscape under different strain states is responsible for the tunable negative capacitance. Our work paves the way for fabricating low-power devices and further reducing energy consumption in electronics.
具有负电容效应的铁电体可以在场效应晶体管中放大栅极电压，以实现超越玻尔兹曼极限的低功耗运行。功耗的降低取决于铁电层与栅极电介质之间的电容匹配，这可以通过调节铁电体中的负电容效应来很好地控制。然而，通过实验调节负电容效应是一个巨大的挑战。在此，展示了通过应变工程在铁电体铌酸钾（KNbO）中观察到的可调谐负电容效应。作为负电容效应标志的极化 - 电场（P - E）曲线中的电压降低幅度和负斜率可以通过施加各种外延应变来控制。不同应变状态下极化 - 能量景观中负曲率区域的调整导致了可调谐负电容。我们的工作为制造低功耗器件以及进一步降低电子设备中的能耗铺平了道路。
