摘要
Two-dimensional(2D)ferroelectrics with high Curie temperature(T_(c))exhibit stable ferroelectricity at the nanoscale and possess significant applications in the miniaturization of ferroelectric devices.However,controllable growth of wafer-scale 2D ferroelectric films with desired thickness is still rarely reported.In this study,we develop a two-step vapour deposition method to grow wafer-scale 2D CuCrS_(2)ferroelectric films with a uniform thickness from 2 to 10 nm.These films possess a non-centrosymmetric structure with a 3R stacking sequence,exhibit ferroelectric polarizations,and the Tc of CuCrS_(2)is higher than room temperature.The constructed electronic devices exhibit the characteristics of ferroelectric memristor,which opens up applications for ferroelectric functional devices.
二维铁电体在纳米尺度上拥有自发极化特性,能够通过外加电场进行动态、可逆和非易失性调控,因此在铁电器件小型化方面具有重要应用前景.其中,二维CuCrS_(2)因层间Cu离子迁移产生的铁电极化特性和自身的高居里温度(Tc)而备受关注,但其晶圆级、厚度可控的制备仍面临挑战.在本工作中,我们采用两步气相沉积方法实现了晶圆级CuCrS_(2)薄膜的可控制备,其厚度在2–10 nm范围内连续可调.薄膜表现出非中心对称性、室温下稳定的铁电性以及远高于室温的Tc,基于薄膜构建的电子器件表现出铁电忆阻器特性,本工作为铁电功能器件的应用开辟了道路.
基金
the National Natural Science Foundation of China(52425203,52221001,62090035,12404216)
the Natural Science Foundation of Jiangsu Province(BK20240008,BK20241252,BK20233001)
the National Key R&D Program of China(2022YFA1204300)
the Key Research and Development Plan of Hunan Province(2023GK2012)
the Postdoctoral Fellowship Program of China Postdoctoral Science Foundation(GZC20231093)
the Jiangsu Funding Program for Excellent Postdoctoral Talent(2023ZB553)。
