Two-dimensional(2D)van der Waals semiconductors are appealing for low-power transistors.Here,we show the feasibility in enhancing carrier mobility in 2D semiconductors through engineering the vertical distribution of ...Two-dimensional(2D)van der Waals semiconductors are appealing for low-power transistors.Here,we show the feasibility in enhancing carrier mobility in 2D semiconductors through engineering the vertical distribution of carriers confined inside ultrathin channels via symmetrizing gate configuration or increasing channel thickness.Through self-consistently solving the Schr¨odinger–Poisson equations,the shapes of electron envelope functions are extensively investigated by clarifying their relationship with gate configuration,channel thickness,dielectric permittivity,and electron density.The impacts of electron distribution variation on various carrier scattering matrix elements and overall carrier mobility are insightfully clarified.It is found that the carrier mobility can be generally enhanced in the dual-gated configuration due to the centralization of carrier redistribution in the nanometer-thick semiconductor channels and the rate of increase reaches up to 23%in Hf O2 dual-gated 10-layer MoS_(2) channels.This finding represents a viable strategy for performance optimization in transistors consisting of 2D semiconductors.展开更多
Two-dimensional(2D)semiconductors have attracted considerable interest for their unique physical properties.Here,we report the intrinsic cryogenic electronic transport properties in few-layer MoSe_(2)field-effect tran...Two-dimensional(2D)semiconductors have attracted considerable interest for their unique physical properties.Here,we report the intrinsic cryogenic electronic transport properties in few-layer MoSe_(2)field-effect transistors(FETs)that are fully encapsulated in ultraclean hexagonal boron nitride dielectrics and are simultaneously van der Waals contacted with gold electrodes.The FETs exhibit electronically favorable channel/dielectric interfaces with low densities of interfacial traps(<1010cm^(-2)),which lead to outstanding device characteristics at room temperature,including near-Boltzmann-limit subthreshold swings(65 mV/dec),high carrier mobilities(53–68 cm^(2)·V-1·s^(-1)),and negligible scanning hystereses(<15 mV).The dependence of various contact-related parameters with temperature and carrier density is also systematically characterized to understand the van der Waals contacts between gold and MoSe_(2).The results provide insightful information about the device physics in van der Waals contacted and encapsulated 2D FETs.展开更多
基金supported by the National Key R&D Program of China(2022YFA1203802 and 2021YFA1202903)the National Natural Science Foundation of China(92264202,61974060 and 61674080)the Innovation and Entrepreneurship Program of Jiangsu Province.
基金the National Key R&D Program of China(Grant Nos.2022YFA1203802 and 2021YFA1202903)the National Natural Science Foundation of China(Grant Nos.92264202,61974060,and 61674080)the Innovation and Entrepreneurship Program of Jiangsu Province。
文摘Two-dimensional(2D)van der Waals semiconductors are appealing for low-power transistors.Here,we show the feasibility in enhancing carrier mobility in 2D semiconductors through engineering the vertical distribution of carriers confined inside ultrathin channels via symmetrizing gate configuration or increasing channel thickness.Through self-consistently solving the Schr¨odinger–Poisson equations,the shapes of electron envelope functions are extensively investigated by clarifying their relationship with gate configuration,channel thickness,dielectric permittivity,and electron density.The impacts of electron distribution variation on various carrier scattering matrix elements and overall carrier mobility are insightfully clarified.It is found that the carrier mobility can be generally enhanced in the dual-gated configuration due to the centralization of carrier redistribution in the nanometer-thick semiconductor channels and the rate of increase reaches up to 23%in Hf O2 dual-gated 10-layer MoS_(2) channels.This finding represents a viable strategy for performance optimization in transistors consisting of 2D semiconductors.
基金the National Key R&D Program of China(Grant Nos.2022YFA1203802 and 2021YFA1202903)the National Natural Science Foundation of China(Grant Nos.92264202,61974060,and 61674080)the Innovation and Entrepreneurship Program of Jiangsu Province。
文摘Two-dimensional(2D)semiconductors have attracted considerable interest for their unique physical properties.Here,we report the intrinsic cryogenic electronic transport properties in few-layer MoSe_(2)field-effect transistors(FETs)that are fully encapsulated in ultraclean hexagonal boron nitride dielectrics and are simultaneously van der Waals contacted with gold electrodes.The FETs exhibit electronically favorable channel/dielectric interfaces with low densities of interfacial traps(<1010cm^(-2)),which lead to outstanding device characteristics at room temperature,including near-Boltzmann-limit subthreshold swings(65 mV/dec),high carrier mobilities(53–68 cm^(2)·V-1·s^(-1)),and negligible scanning hystereses(<15 mV).The dependence of various contact-related parameters with temperature and carrier density is also systematically characterized to understand the van der Waals contacts between gold and MoSe_(2).The results provide insightful information about the device physics in van der Waals contacted and encapsulated 2D FETs.
