High-quality and large-scale growth of monolayer molybdenum disulfide(MoS2)has caught intensive attention because of its potential in many applications due to unique electronic properties.Here,we report the wafer-scal...High-quality and large-scale growth of monolayer molybdenum disulfide(MoS2)has caught intensive attention because of its potential in many applications due to unique electronic properties.Here,we report the wafer-scale growth of high-quality mono layer MoS2 on singlecrystalline sapphire and also on SiO2 substrates by a facile metal-organic chemical vapor deposit!on(MOCVD)method.Prior to growth,an aqueous solution of sodium molybdate(Na2MoO4)is spun onto the substrates as the molybdenum precursor and diethyl sulfide((C2H5)2S)is used as the sulfur precursor duri ng the growth.The grown MoS2 films exhibit crystal I i nity,good electrical performa nee(electro n mobility of 22 cm2·V^-1·s^-1)and structural continuity maintained over the entire wafer.The sapphire substrates are reusable for subsequent growth.The same method is applied for the synthesis of tungsten disulfide(WS2).Our work provides a facile,reproducible and cost-efficient method for the scalable fabricati on of high-quality mono layer MoS2 for versatile applicati ons,such as electro nic and optoelectr onic devices as well as the membranes for desalination and power generation.展开更多
Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertic...Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertical resolution below 1 nm,but its maximum depth in polymers is limited.Here,we present an innovative combination of nanowriting in thermal resist and plasma dry etching with substrate cooling,which achieves up to 10-fold amplification of polymer nanopatterns into SiO_(2) without proportionally increasing surface roughness.Sinusoidal nanopatterns in SiO_(2) with 400 nm pitch and 150 nm depth are fabricated free of shape distortion after dry etching.To exemplify the possible applications of the proposed method,grayscale dielectric nanostructures are used for scalable manufacturing through nanoimprint lithography and for strain nanoengineering of 2D materials.Such a method for aspect ratio amplification and smooth grayscale nanopatterning has the potential to find application in the fabrication of photonic and nanoelectronic devices.展开更多
文摘High-quality and large-scale growth of monolayer molybdenum disulfide(MoS2)has caught intensive attention because of its potential in many applications due to unique electronic properties.Here,we report the wafer-scale growth of high-quality mono layer MoS2 on singlecrystalline sapphire and also on SiO2 substrates by a facile metal-organic chemical vapor deposit!on(MOCVD)method.Prior to growth,an aqueous solution of sodium molybdate(Na2MoO4)is spun onto the substrates as the molybdenum precursor and diethyl sulfide((C2H5)2S)is used as the sulfur precursor duri ng the growth.The grown MoS2 films exhibit crystal I i nity,good electrical performa nee(electro n mobility of 22 cm2·V^-1·s^-1)and structural continuity maintained over the entire wafer.The sapphire substrates are reusable for subsequent growth.The same method is applied for the synthesis of tungsten disulfide(WS2).Our work provides a facile,reproducible and cost-efficient method for the scalable fabricati on of high-quality mono layer MoS2 for versatile applicati ons,such as electro nic and optoelectr onic devices as well as the membranes for desalination and power generation.
基金funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Project MEMS4.0,ERC-2016-ADG,grant agreement No.742685)the EU’s H2020 framework program for research and innovation under grant agreement n.101007417,NFFA-Europe Pilot Project.M.B.acknowledges the support of SNSF Eccellenza grant No.PCEGP2_194528+4 种基金support from the QuantERA II Programme that has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No 101017733G.F.and M.P.received funding through the European research council H2020-UE Framework Programme for Research&Innovation(2014-2020)ERC-2017-CoGInCellProject number 773091,and the Swiss National Science Foundation through grant 200021_182562.
文摘Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertical resolution below 1 nm,but its maximum depth in polymers is limited.Here,we present an innovative combination of nanowriting in thermal resist and plasma dry etching with substrate cooling,which achieves up to 10-fold amplification of polymer nanopatterns into SiO_(2) without proportionally increasing surface roughness.Sinusoidal nanopatterns in SiO_(2) with 400 nm pitch and 150 nm depth are fabricated free of shape distortion after dry etching.To exemplify the possible applications of the proposed method,grayscale dielectric nanostructures are used for scalable manufacturing through nanoimprint lithography and for strain nanoengineering of 2D materials.Such a method for aspect ratio amplification and smooth grayscale nanopatterning has the potential to find application in the fabrication of photonic and nanoelectronic devices.
