Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high...Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power nanoelectronics.Despite the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant challenge.Herein,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) crystals.Switchable polarization is observed in thin SnP_(2)S_(6) of~7 nm.Importantly,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic layers.In addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) Jones.Our results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.展开更多
基金This work was supported by the National Key Research and Development Program of China(Nos.2021YFE0194200 and 2021YFA1200903)the National Natural Science Foundation of China(No.22175203)+2 种基金the Natural Science Foundation of Guangdong Province(Nos.2022B1515020065 and 2020A1515110821)the Guangzhou Science and Technology Project(No.202102020126)This work was also supported by the Plan Fostering Project of State Key Laboratory of Optoelectronic Materials and Technologies,of Sun Yatsen University(No.OEMT-2021-PZ-02).
文摘Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power nanoelectronics.Despite the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant challenge.Herein,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) crystals.Switchable polarization is observed in thin SnP_(2)S_(6) of~7 nm.Importantly,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic layers.In addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) Jones.Our results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.
