石墨烯器件作为下一代纳米电子器件的有力竞争者受到广泛关注,但对其器件工作机理的研究尚不透彻。对石墨烯纳米带场效应晶体管(graphene nanoribbon field effect transistor,GNRFET)的双极特性进行了研究,分析了偏置电压对GNRFET转移...石墨烯器件作为下一代纳米电子器件的有力竞争者受到广泛关注,但对其器件工作机理的研究尚不透彻。对石墨烯纳米带场效应晶体管(graphene nanoribbon field effect transistor,GNRFET)的双极特性进行了研究,分析了偏置电压对GNRFET转移特性和输出特性的影响,发现除已被关注到的栅电压外,源漏电压对GNRFET的双极特性亦有作用,并将两者综合考虑才能全面反映GNRFET的工作状态。在此基础上,进一步提出了工作区域的概念,将GNR-FET的工作区域划分为空穴导电区、电子导电区、转变区和截止区,为GNRFET器件的应用和电路设计提供指导。展开更多
This paper presents a novel approach with Graphene devices that are highly sensitive in detecting IR energy. Current non-imaging techniques like ultrasonography have been proposed for thyroid diagnosis with limitation...This paper presents a novel approach with Graphene devices that are highly sensitive in detecting IR energy. Current non-imaging techniques like ultrasonography have been proposed for thyroid diagnosis with limitations on ability to detect low-temperature distribution around the hot spot at the starting stage of the thyroid hyperthyroidism. The energy distribution around hotspot is minimal at the beginning stage. This detection may require ultra-high sensitive materials to the IR energy. A computer modeling using COMSOL software shows the thermal energy simulation of a thyroid gland with single or multiple active nodules. Data collection of the energy levels and condition of thyroid in the human body support the work investigated in this study. The study conducted here has shown as low as 0.1 - 5 mW IR power can be detected based on the Graphene device sensitivity. The paper details the simulation and approach for this non-invasive diagnosis.展开更多
We perform a theoretical study of the effects of the lightly doped drain (LDD) and high-k dielectric on the performances of double gate p-i-n tunneling graphene nanoribbon field effect transistors (TFETs). The mod...We perform a theoretical study of the effects of the lightly doped drain (LDD) and high-k dielectric on the performances of double gate p-i-n tunneling graphene nanoribbon field effect transistors (TFETs). The models are based on non-equilibrium Green's functions (NEGF) solved self-consistently with 3D-Poisson's equations. For the first time, hetero gate dielectric and single LDD TFETs (SL-HTFETs) are proposed and investigated. Simulation results show SL-HTFETs can effectively decrease leakage current, sub-threshold swing, and increase on-off current ratio compared to conventional TFETs and Si-based devices; the SL-HTFETs from the 3p + 1 family have better switching characteristics than those from the 3p family due to smaller effective masses of the former. In addition, comparison of scaled performances between SL-HTFETs and conventional TFETs show that SL-HTFETs have better scaling properties than the conventional TFETs, and thus could be promising devices for logic and ultra-low power applications.展开更多
文摘石墨烯器件作为下一代纳米电子器件的有力竞争者受到广泛关注,但对其器件工作机理的研究尚不透彻。对石墨烯纳米带场效应晶体管(graphene nanoribbon field effect transistor,GNRFET)的双极特性进行了研究,分析了偏置电压对GNRFET转移特性和输出特性的影响,发现除已被关注到的栅电压外,源漏电压对GNRFET的双极特性亦有作用,并将两者综合考虑才能全面反映GNRFET的工作状态。在此基础上,进一步提出了工作区域的概念,将GNR-FET的工作区域划分为空穴导电区、电子导电区、转变区和截止区,为GNRFET器件的应用和电路设计提供指导。
文摘This paper presents a novel approach with Graphene devices that are highly sensitive in detecting IR energy. Current non-imaging techniques like ultrasonography have been proposed for thyroid diagnosis with limitations on ability to detect low-temperature distribution around the hot spot at the starting stage of the thyroid hyperthyroidism. The energy distribution around hotspot is minimal at the beginning stage. This detection may require ultra-high sensitive materials to the IR energy. A computer modeling using COMSOL software shows the thermal energy simulation of a thyroid gland with single or multiple active nodules. Data collection of the energy levels and condition of thyroid in the human body support the work investigated in this study. The study conducted here has shown as low as 0.1 - 5 mW IR power can be detected based on the Graphene device sensitivity. The paper details the simulation and approach for this non-invasive diagnosis.
文摘We perform a theoretical study of the effects of the lightly doped drain (LDD) and high-k dielectric on the performances of double gate p-i-n tunneling graphene nanoribbon field effect transistors (TFETs). The models are based on non-equilibrium Green's functions (NEGF) solved self-consistently with 3D-Poisson's equations. For the first time, hetero gate dielectric and single LDD TFETs (SL-HTFETs) are proposed and investigated. Simulation results show SL-HTFETs can effectively decrease leakage current, sub-threshold swing, and increase on-off current ratio compared to conventional TFETs and Si-based devices; the SL-HTFETs from the 3p + 1 family have better switching characteristics than those from the 3p family due to smaller effective masses of the former. In addition, comparison of scaled performances between SL-HTFETs and conventional TFETs show that SL-HTFETs have better scaling properties than the conventional TFETs, and thus could be promising devices for logic and ultra-low power applications.