完美石墨烯由于具有高导电性、高透光性、高柔韧性、高阻隔性、高机械强度、高化学稳定性、超薄等特性,被誉为21世纪最具颠覆性的“新材料之王”,引起全球各界的关注,并预期在电子领域、光子领域、能源领域、环保领域、生物医疗健康等...完美石墨烯由于具有高导电性、高透光性、高柔韧性、高阻隔性、高机械强度、高化学稳定性、超薄等特性,被誉为21世纪最具颠覆性的“新材料之王”,引起全球各界的关注,并预期在电子领域、光子领域、能源领域、环保领域、生物医疗健康等领域具有广阔的发展前景。目前,欧洲、美国、日本等众多国家,都把石墨烯列为本世纪最重要的新材料进行研究和开发,并已在新能源、电子等方面取得重要进展和初步应用效果。我国也明确把石墨烯作为国家重要战略材料列入国家“十三五”规划。石墨烯分为石墨烯粉体(还原氧化石墨烯)和石墨烯薄膜两大类。目前研究较多的是石墨烯粉体,且其制备和应用方面都有了系统的研究,并取得了一定成果。对于石墨烯薄膜,研究较多的是其制备技术,虽然对石墨烯薄膜在各个领域的应用均进行了初步研究,验证了它应用于其中的可行性,并预期其在部分应用领域具有显著优势,但多数处于研究初期,还面临众多技术挑战。因为目前制备的石墨烯薄膜性能和理论性能有较大差距,所以需要研究者们一方面改进制备技术,提升石墨烯薄膜性能;另一方面结合石墨烯特性选择拥有显著优势的应用领域进行深入研究,设计能够体现石墨烯薄膜性能优势的产品器件,这样才能真正打开石墨烯薄膜的应用市场。本文首先介绍了化学气相沉积法制备石墨烯薄膜的研究现状及发展趋势。目前,石墨烯薄膜晶畴尺寸多为微米级到毫米级,少数研究机构所制的石墨烯薄膜晶畴可达到厘米级;石墨烯薄膜迁移率一般可达到10000~30000 cm 2/(V·s),方阻小于150Ω/□,透光率达到97.7%。石墨烯薄膜发展趋势是开发可控、快速制备大面积、大晶畴、高质量原位沉积石墨烯薄膜的技术和找到可体现石墨烯薄膜优异性能的应用场景。其次在欧盟“石墨烯旗舰计展开更多
本文针对不同结构、尺寸的石墨烯场效应晶体管(graphene field effect transistors,GFET)开展了基于10 keV-X射线的总剂量效应研究.结果表明,随累积剂量的增大,不同结构GFET的狄拉克电压V_(Dirac)和载流子迁移率μ不断退化;相比于背栅型...本文针对不同结构、尺寸的石墨烯场效应晶体管(graphene field effect transistors,GFET)开展了基于10 keV-X射线的总剂量效应研究.结果表明,随累积剂量的增大,不同结构GFET的狄拉克电压V_(Dirac)和载流子迁移率μ不断退化;相比于背栅型GFET,顶栅型GFET的辐射损伤更加严重;尺寸对GFET器件的总剂量效应决定于器件结构;200μm×200μm尺寸的顶栅型GFET损伤最严重,而背栅型GFET是50μm×50μm尺寸的器件损伤最严重.研究表明:对于顶栅型GFET,辐照过程中在栅氧层中形成的氧化物陷阱电荷的积累是V_(Dirac)和μ降低的主要原因.背栅型GFET不仅受到辐射在栅氧化层中产生的陷阱电荷的影响,还受到石墨烯表面的氧吸附的影响.在此基础上,结合TCAD仿真工具实现了顶栅器件氧化层中辐射产生的氧化物陷阱电荷对器件辐射响应规律的仿真.相关研究结果对于石墨烯器件的抗辐照加固研究具有重大意义.展开更多
We report the fabrication and characterization of a single-layer graphene field-effect terahertz detector, which is cou- pled with dipole-like antennas based on the self-mixing detector model. The graphene is grown by...We report the fabrication and characterization of a single-layer graphene field-effect terahertz detector, which is cou- pled with dipole-like antennas based on the self-mixing detector model. The graphene is grown by chemical vapor deposi- tion and then transferred onto an SiO2/Si substrate. We demonstrate room-temperature detection at 237 GHz. The detector could offer a voltage responsivity of 0.1 V/W and a noise equivalent power of 207 nW/Hz 1/2. Our modeling indicates that the observed photovoltage in the p-type gated channel can be well fit by the self-mixing theory. A different photoresponse other than self-mixing may apply for the n-type gated channel.展开更多
Reduced graphene oxide （RGO） has the advantage of an aqueous and industrial-scale production route. No other approaches can rival the RGO field effect transistor platform in terms of cost （〈US$1） and portability ...Reduced graphene oxide （RGO） has the advantage of an aqueous and industrial-scale production route. No other approaches can rival the RGO field effect transistor platform in terms of cost （〈US$1） and portability （millimetre scale）. However the large deviations in the electrical resistivity of this fabricated material prevent it from being used widely. After an ethanol chemical vapor deposition （CVD） post-treatment to graphene oxide with ethanol, carbon islets are deposited preferentially at the edges of existing flakes. With a 2-h treatment, the standard deviation in electrical resistance of the treated chips can be reduced by 99.95%. Thus this process could enable RGO to be used in practical electronic devices.展开更多
The graphene field effect transistor （GFET） has been widely studied and developed as sensors and functional devices. The first report about GFET sensing simulation on the device level is proposed. The GFET＇s charac...The graphene field effect transistor （GFET） has been widely studied and developed as sensors and functional devices. The first report about GFET sensing simulation on the device level is proposed. The GFET＇s characteristics, its responding for single strand DNA （ssDNA） and hybridization with the complimentary DNA （cDNA） are simulated based on Sentaurus, a popular CAD tool for electronic devices. The agreement between the simulated blank GFET feature and the reported experimental data suggests the feasibility of the presented simulation method. Then the simulations of ssDNA immobilization on GFET and hybridization with its cDNA are performed, the results are discussed based on the electron transfer （ET） mechanism between DNA and graphene.展开更多
文摘完美石墨烯由于具有高导电性、高透光性、高柔韧性、高阻隔性、高机械强度、高化学稳定性、超薄等特性,被誉为21世纪最具颠覆性的“新材料之王”,引起全球各界的关注,并预期在电子领域、光子领域、能源领域、环保领域、生物医疗健康等领域具有广阔的发展前景。目前,欧洲、美国、日本等众多国家,都把石墨烯列为本世纪最重要的新材料进行研究和开发,并已在新能源、电子等方面取得重要进展和初步应用效果。我国也明确把石墨烯作为国家重要战略材料列入国家“十三五”规划。石墨烯分为石墨烯粉体(还原氧化石墨烯)和石墨烯薄膜两大类。目前研究较多的是石墨烯粉体,且其制备和应用方面都有了系统的研究,并取得了一定成果。对于石墨烯薄膜,研究较多的是其制备技术,虽然对石墨烯薄膜在各个领域的应用均进行了初步研究,验证了它应用于其中的可行性,并预期其在部分应用领域具有显著优势,但多数处于研究初期,还面临众多技术挑战。因为目前制备的石墨烯薄膜性能和理论性能有较大差距,所以需要研究者们一方面改进制备技术,提升石墨烯薄膜性能;另一方面结合石墨烯特性选择拥有显著优势的应用领域进行深入研究,设计能够体现石墨烯薄膜性能优势的产品器件,这样才能真正打开石墨烯薄膜的应用市场。本文首先介绍了化学气相沉积法制备石墨烯薄膜的研究现状及发展趋势。目前,石墨烯薄膜晶畴尺寸多为微米级到毫米级,少数研究机构所制的石墨烯薄膜晶畴可达到厘米级;石墨烯薄膜迁移率一般可达到10000~30000 cm 2/(V·s),方阻小于150Ω/□,透光率达到97.7%。石墨烯薄膜发展趋势是开发可控、快速制备大面积、大晶畴、高质量原位沉积石墨烯薄膜的技术和找到可体现石墨烯薄膜优异性能的应用场景。其次在欧盟“石墨烯旗舰计
文摘本文针对不同结构、尺寸的石墨烯场效应晶体管(graphene field effect transistors,GFET)开展了基于10 keV-X射线的总剂量效应研究.结果表明,随累积剂量的增大,不同结构GFET的狄拉克电压V_(Dirac)和载流子迁移率μ不断退化;相比于背栅型GFET,顶栅型GFET的辐射损伤更加严重;尺寸对GFET器件的总剂量效应决定于器件结构;200μm×200μm尺寸的顶栅型GFET损伤最严重,而背栅型GFET是50μm×50μm尺寸的器件损伤最严重.研究表明:对于顶栅型GFET,辐照过程中在栅氧层中形成的氧化物陷阱电荷的积累是V_(Dirac)和μ降低的主要原因.背栅型GFET不仅受到辐射在栅氧化层中产生的陷阱电荷的影响,还受到石墨烯表面的氧吸附的影响.在此基础上,结合TCAD仿真工具实现了顶栅器件氧化层中辐射产生的氧化物陷阱电荷对器件辐射响应规律的仿真.相关研究结果对于石墨烯器件的抗辐照加固研究具有重大意义.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61271157,61401456,and 11403084)Jiangsu Provincial Planned Projects for Postdoctoral Research Funds(Grant No.1301054B)+4 种基金the Fund from Suzhou Industry Technology Bureau(Grant No.ZXG2012024)China Postdoctoral Science Foundation(Grant No.2014M551678)the Graduate Student Innovation Program for Universities of Jiangsu Province(Grant No.CXLX12-0724)the Fundamental Research Funds for the Central Universities(Grant No.JUDCF 12032)the Fund from National University of Defense Technology(Grant No.JC13-02-14)
文摘We report the fabrication and characterization of a single-layer graphene field-effect terahertz detector, which is cou- pled with dipole-like antennas based on the self-mixing detector model. The graphene is grown by chemical vapor deposi- tion and then transferred onto an SiO2/Si substrate. We demonstrate room-temperature detection at 237 GHz. The detector could offer a voltage responsivity of 0.1 V/W and a noise equivalent power of 207 nW/Hz 1/2. Our modeling indicates that the observed photovoltage in the p-type gated channel can be well fit by the self-mixing theory. A different photoresponse other than self-mixing may apply for the n-type gated channel.
基金Project supported by the Institute for Sports Research(ISR)of Nanyang Technological University(NTU),the National Institute for Health Research(NIHR)Diet,Lifestyle&Physical Activity Biomedical Research Unit based at University Hospitals of Leicester and Loughborough University,and the International Graduate School Bio-Nano-Techa Joint Ph D Program of University of Natural Resources and Life Sciences Vienna(BOKU),the Austrian Institute of Technology(AIT)and NTU
文摘Reduced graphene oxide （RGO） has the advantage of an aqueous and industrial-scale production route. No other approaches can rival the RGO field effect transistor platform in terms of cost （〈US$1） and portability （millimetre scale）. However the large deviations in the electrical resistivity of this fabricated material prevent it from being used widely. After an ethanol chemical vapor deposition （CVD） post-treatment to graphene oxide with ethanol, carbon islets are deposited preferentially at the edges of existing flakes. With a 2-h treatment, the standard deviation in electrical resistance of the treated chips can be reduced by 99.95%. Thus this process could enable RGO to be used in practical electronic devices.
基金supported by the National Natural Science Foundation of China(No.61371028)the Tianjin Natural Science Foundation(No.12JCZDJC22400)
文摘The graphene field effect transistor （GFET） has been widely studied and developed as sensors and functional devices. The first report about GFET sensing simulation on the device level is proposed. The GFET＇s characteristics, its responding for single strand DNA （ssDNA） and hybridization with the complimentary DNA （cDNA） are simulated based on Sentaurus, a popular CAD tool for electronic devices. The agreement between the simulated blank GFET feature and the reported experimental data suggests the feasibility of the presented simulation method. Then the simulations of ssDNA immobilization on GFET and hybridization with its cDNA are performed, the results are discussed based on the electron transfer （ET） mechanism between DNA and graphene.
