The field of metasurface research has rapidly developed in the past decade.Electron-beam lithography(EBL)is an excellent tool used for rapid prototyping of metasurfaces.However,Gaussian-beam EBL generally struggles wi...The field of metasurface research has rapidly developed in the past decade.Electron-beam lithography(EBL)is an excellent tool used for rapid prototyping of metasurfaces.However,Gaussian-beam EBL generally struggles with low throughput.In conjunction with the recent rise of interest in metasurfaces made of low-index dielectric materials,we propose in this study the use of a relatively unexplored chemically amplified resist,SU-8 with EBL,as a method for rapid prototyping of low-index metasurfaces.We demonstrate the use of SU-8 grating on silicon for cost-efficient fabrication of an all-dielectric multilevel security print for anti-counterfeiting purposes,which encrypt different optical information with different light illumination conditions,namely,bright-field reflection,dark-field reflection,and cross-polarized reflection.The large-scale print(1 mm^(2))could be exposed in a relatively short time(~11 min)due to the ultrahigh sensitivity of the resist,while the feature size of~200 nm was maintained,demonstrating that SU-8 EBL resist serves as a good candidate for rapid prototyping of metasurface designs.Our results could find applications in the general area of increasing EBL patterning speed for a variety of other devices and structures.展开更多
Reducing the process variation is a significant concern for resistive random access memory(RRAM).Due to its ultrahigh integration density,RRAM arrays are prone to lithographic variation during the lithography process,...Reducing the process variation is a significant concern for resistive random access memory(RRAM).Due to its ultrahigh integration density,RRAM arrays are prone to lithographic variation during the lithography process,introducing electrical variation among different RRAM devices.In this work,an optical physical verification methodology for the RRAM array is developed,and the effects of different layout parameters on important electrical characteristics are systematically investigated.The results indicate that the RRAM devices can be categorized into three clusters according to their locations and lithography environments.The read resistance is more sensitive to the locations in the array(~30%)than SET/RESET voltage(<10%).The increase in the RRAM device length and the application of the optical proximity correction technique can help to reduce the variation to less than 10%,whereas it reduces RRAM read resistance by 4×,resulting in a higher power and area consumption.As such,we provide design guidelines to minimize the electrical variation of RRAM arrays due to the lithography process.展开更多
We present a method for submicron fabrication of flexible,thin-film structures fully encapsulated in biocompatible polymer poly(chloro-p-xylylene)(Parylene C)that improves feature size and resolution by an order of ma...We present a method for submicron fabrication of flexible,thin-film structures fully encapsulated in biocompatible polymer poly(chloro-p-xylylene)(Parylene C)that improves feature size and resolution by an order of magnitude compared with prior work.We achieved critical dimensions as small as 250 nm by adapting electron beam lithography for use on vapor deposited Parylene-coated substrates and fabricated encapsulated metal structures,including conducting traces,serpentine resistors,and nano-patterned electrodes.Structures were probed electrically and mechanically demonstrating robust performance even under flexion or torsion.The developed fabrication process for electron beam lithography on Parylene-coated substrates and characterization of the resulting structures are presented in addition to a discussion of the challenges of applying electron beam lithography to polymers.As an application of the technique,a Parylene-based neural probe prototype was fabricated with 32 recording sites patterned along a 2 mm long shank,an electrode density surpassing any prior polymer probe.展开更多
Chromium atom photolithography gratings are a promising technology for the development of nanoscale length standard substances due to their high accuracy,uniformity,and consistency.However,the inherent difference betw...Chromium atom photolithography gratings are a promising technology for the development of nanoscale length standard substances due to their high accuracy,uniformity,and consistency.However,the inherent difference between the interaction of positive and negative frequency detuning standing wave field and the atoms can cause a difference in the adjacent peak-to-valley heights of the grating in positive and negative frequency detuning chromium atom lithography,which greatly reduces its accuracy.In this study,we performed a controlled variable growth simulation using the semi-classical theoretical model and Monte Carlo method with trajectory tracking and ballistic deposition methods to investigate the influence of key experimental parameters on the surface growth process of positive and negative frequency detuning atomic lithography gratings.We established a theoretical model based on simulation results and summarized empirical equations to guide the selection of experimental parameters.Our simulations achieved uniform positive and negative frequency detuning atomic lithography gratings with a period of 1/4 of the wavelength corresponding to the atomic transition frequency,and adjacent peak-to-valley heights differing by no more than 2 nm,providing an important theoretical reference for the controllable fabrication of these gratings.展开更多
This paper provides insight into the application of electron-beam welding in pellet mold preparation,highlighting the importance of the combination of electron-beam welding and pellet mold preparation in the fields of...This paper provides insight into the application of electron-beam welding in pellet mold preparation,highlighting the importance of the combination of electron-beam welding and pellet mold preparation in the fields of microstructure joining and micro-and nanostructure preparation.Precise material joining and microstructure fabrication can be achieved by the precise control of electron-beam welding and the shape adjustment of pellet molds.These applications hold significant potential in the modern industrial field,providing robust support for the development of new materials and the growth of the petrochemical industry.This paper asserts that in the future,the ongoing development of electron-beam welding and pelletizing template technology will unlock new possibilities in the field of petrochemicals,fostering progress in science and technology.展开更多
This paper provides an in-depth discussion of the joint strength of electron beam welding of dissimilar materials.The effect of welding parameters and material properties on the joint strength was analyzed,and an argu...This paper provides an in-depth discussion of the joint strength of electron beam welding of dissimilar materials.The effect of welding parameters and material properties on the joint strength was analyzed,and an argument for the optimal parameter combination is presented.Electron-beam welding technology offers several advantages,including high energy density and the ability to create fine weld seams.However,it also presents certain challenges,such as the complexity of welding parameters and the potential generation of brittle phases.The analysis conducted in this paper holds significant importance in enhancing the quality and efficiency of dissimilar material welding processes.展开更多
The development of nanoelectronics and nanotechnologies has been boosted significantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patte...The development of nanoelectronics and nanotechnologies has been boosted significantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patterning technology for single-layer 2D materials is critical for assembling nanodevices.Demonstrated here is a nanomachining technique using electrical breakdown by an AFM tip to fabricate nanopores,nanostrips,and other nanostructures on demand.This can be achieved by voltage scanning or applying a constant voltage while moving the tip.By measuring the electrical current,the formation process on single-layer materials was shown quantitatively.The present results provide evidence of successful pattern fabrication on single-layer MoS2,boron nitride,and graphene,although further confirmation is still needed.The proposed method holds promise as a general nanomachining technology for the future.展开更多
ASET, Association of Super-advanced Electronics Technologies, has been taking the initiative in developing EUV lithography technology in Japan for the past three years. The aspherical mirror metrology using a visible ...ASET, Association of Super-advanced Electronics Technologies, has been taking the initiative in developing EUV lithography technology in Japan for the past three years. The aspherical mirror metrology using a visible light point diffraction interferometer (PDI), the wave front measurement using an at-wavelength PDI, and an at wavelength reflectometry for multilayers, various imaging simulations, multilayer coatings for the mask, the development of absorber materials for mask patterning, the mask substrate cleaning technique, and various photoresist processes have been developed. The visible light PDI employs a 0.5-μm pinhole as an aperture to generate an ideal spherical wave front and can measure a 0.3-N A mirror maximum. The at-wavelength PDI can measure the wave front error of the projection optics. The at-wavelength reflectometer can measure the reflectivity of multilayers and the round-robin test is taking place among ASET, the ALS in Lawrence Berkeley, and BESSY in Germany. The mask cleaning technique employs a supersonic hydro-cleaning technique. We have confirmed that the single layer resists can be used for EUV lithography.展开更多
基金National Research Foundation Singapore(NRF-CRP20-2017-0004,NRF-NRFI06-2020-0005)。
文摘The field of metasurface research has rapidly developed in the past decade.Electron-beam lithography(EBL)is an excellent tool used for rapid prototyping of metasurfaces.However,Gaussian-beam EBL generally struggles with low throughput.In conjunction with the recent rise of interest in metasurfaces made of low-index dielectric materials,we propose in this study the use of a relatively unexplored chemically amplified resist,SU-8 with EBL,as a method for rapid prototyping of low-index metasurfaces.We demonstrate the use of SU-8 grating on silicon for cost-efficient fabrication of an all-dielectric multilevel security print for anti-counterfeiting purposes,which encrypt different optical information with different light illumination conditions,namely,bright-field reflection,dark-field reflection,and cross-polarized reflection.The large-scale print(1 mm^(2))could be exposed in a relatively short time(~11 min)due to the ultrahigh sensitivity of the resist,while the feature size of~200 nm was maintained,demonstrating that SU-8 EBL resist serves as a good candidate for rapid prototyping of metasurface designs.Our results could find applications in the general area of increasing EBL patterning speed for a variety of other devices and structures.
基金supported in part by the Open Fund of State Key Laboratory of Integrated Chips and Systems,Fudan Universityin part by the National Science Foundation of China under Grant No.62304133 and No.62350610271.
文摘Reducing the process variation is a significant concern for resistive random access memory(RRAM).Due to its ultrahigh integration density,RRAM arrays are prone to lithographic variation during the lithography process,introducing electrical variation among different RRAM devices.In this work,an optical physical verification methodology for the RRAM array is developed,and the effects of different layout parameters on important electrical characteristics are systematically investigated.The results indicate that the RRAM devices can be categorized into three clusters according to their locations and lithography environments.The read resistance is more sensitive to the locations in the array(~30%)than SET/RESET voltage(<10%).The increase in the RRAM device length and the application of the optical proximity correction technique can help to reduce the variation to less than 10%,whereas it reduces RRAM read resistance by 4×,resulting in a higher power and area consumption.As such,we provide design guidelines to minimize the electrical variation of RRAM arrays due to the lithography process.
基金funded by a Postdoctoral Scholar Research Grant from the Office of the Provost at USC.
文摘We present a method for submicron fabrication of flexible,thin-film structures fully encapsulated in biocompatible polymer poly(chloro-p-xylylene)(Parylene C)that improves feature size and resolution by an order of magnitude compared with prior work.We achieved critical dimensions as small as 250 nm by adapting electron beam lithography for use on vapor deposited Parylene-coated substrates and fabricated encapsulated metal structures,including conducting traces,serpentine resistors,and nano-patterned electrodes.Structures were probed electrically and mechanically demonstrating robust performance even under flexion or torsion.The developed fabrication process for electron beam lithography on Parylene-coated substrates and characterization of the resulting structures are presented in addition to a discussion of the challenges of applying electron beam lithography to polymers.As an application of the technique,a Parylene-based neural probe prototype was fabricated with 32 recording sites patterned along a 2 mm long shank,an electrode density surpassing any prior polymer probe.
基金Project supported by the National Natural Science Foundation of China(Grant No.62075165)the National Key Research and Development Program of China(Grant Nos.2022YFF0607600 and 2022YFF0605502)+3 种基金the Special Development Funds for Major Projects of Shanghai Zhangjiang National Independent Innovation Demonstration Zone(Grant No.ZJ2021ZD008)the Shanghai Natural Science Foundation(Grant No.21ZR1483100)the Shanghai Academic/Technology Research Leader(Grant No.21XD1425000)the Opening Fund of Shanghai Key Laboratory of Online Detection and Control Technology(Grant No.ZX2020101)。
文摘Chromium atom photolithography gratings are a promising technology for the development of nanoscale length standard substances due to their high accuracy,uniformity,and consistency.However,the inherent difference between the interaction of positive and negative frequency detuning standing wave field and the atoms can cause a difference in the adjacent peak-to-valley heights of the grating in positive and negative frequency detuning chromium atom lithography,which greatly reduces its accuracy.In this study,we performed a controlled variable growth simulation using the semi-classical theoretical model and Monte Carlo method with trajectory tracking and ballistic deposition methods to investigate the influence of key experimental parameters on the surface growth process of positive and negative frequency detuning atomic lithography gratings.We established a theoretical model based on simulation results and summarized empirical equations to guide the selection of experimental parameters.Our simulations achieved uniform positive and negative frequency detuning atomic lithography gratings with a period of 1/4 of the wavelength corresponding to the atomic transition frequency,and adjacent peak-to-valley heights differing by no more than 2 nm,providing an important theoretical reference for the controllable fabrication of these gratings.
文摘This paper provides insight into the application of electron-beam welding in pellet mold preparation,highlighting the importance of the combination of electron-beam welding and pellet mold preparation in the fields of microstructure joining and micro-and nanostructure preparation.Precise material joining and microstructure fabrication can be achieved by the precise control of electron-beam welding and the shape adjustment of pellet molds.These applications hold significant potential in the modern industrial field,providing robust support for the development of new materials and the growth of the petrochemical industry.This paper asserts that in the future,the ongoing development of electron-beam welding and pelletizing template technology will unlock new possibilities in the field of petrochemicals,fostering progress in science and technology.
文摘This paper provides an in-depth discussion of the joint strength of electron beam welding of dissimilar materials.The effect of welding parameters and material properties on the joint strength was analyzed,and an argument for the optimal parameter combination is presented.Electron-beam welding technology offers several advantages,including high energy density and the ability to create fine weld seams.However,it also presents certain challenges,such as the complexity of welding parameters and the potential generation of brittle phases.The analysis conducted in this paper holds significant importance in enhancing the quality and efficiency of dissimilar material welding processes.
基金supported by the National Natural Science Foundation of China(Grant Nos.12075191,12388101,and 12241201)the Fundamental Research Funds for the Central Universities(Grant No.D5000230120)the Natural Science Basic Research Program of Shaanxi Province(Grant No.2023-JC-YB-541).
文摘The development of nanoelectronics and nanotechnologies has been boosted significantly by the emergence of 2D materials because of their atomic thickness and peculiar properties,and developing a universal,precise patterning technology for single-layer 2D materials is critical for assembling nanodevices.Demonstrated here is a nanomachining technique using electrical breakdown by an AFM tip to fabricate nanopores,nanostrips,and other nanostructures on demand.This can be achieved by voltage scanning or applying a constant voltage while moving the tip.By measuring the electrical current,the formation process on single-layer materials was shown quantitatively.The present results provide evidence of successful pattern fabrication on single-layer MoS2,boron nitride,and graphene,although further confirmation is still needed.The proposed method holds promise as a general nanomachining technology for the future.
文摘ASET, Association of Super-advanced Electronics Technologies, has been taking the initiative in developing EUV lithography technology in Japan for the past three years. The aspherical mirror metrology using a visible light point diffraction interferometer (PDI), the wave front measurement using an at-wavelength PDI, and an at wavelength reflectometry for multilayers, various imaging simulations, multilayer coatings for the mask, the development of absorber materials for mask patterning, the mask substrate cleaning technique, and various photoresist processes have been developed. The visible light PDI employs a 0.5-μm pinhole as an aperture to generate an ideal spherical wave front and can measure a 0.3-N A mirror maximum. The at-wavelength PDI can measure the wave front error of the projection optics. The at-wavelength reflectometer can measure the reflectivity of multilayers and the round-robin test is taking place among ASET, the ALS in Lawrence Berkeley, and BESSY in Germany. The mask cleaning technique employs a supersonic hydro-cleaning technique. We have confirmed that the single layer resists can be used for EUV lithography.