With the rapid development in advanced industries,such as microelectronics and optics sectors,the functional feature size of devises/components has been decreasing from micro to nanometric,and even ACS for higher perf...With the rapid development in advanced industries,such as microelectronics and optics sectors,the functional feature size of devises/components has been decreasing from micro to nanometric,and even ACS for higher performance,smaller volume and lower energy consumption.By this time,a great many quantum structures are proposed,with not only an extreme scale of several or even single atom,but also a nearly ideal lattice structure with no material defect.It is almost no doubt that such structures play critical role in the next generation products,which shows an urgent demand for the ACSM.Laser machining is one of the most important approaches widely used in engineering and scientific research.It is high-efficient and applicable for most kinds of materials.Moreover,the processing scale covers a huge range from millimeters to nanometers,and has already touched the atomic level.Laser–material interaction mechanism,as the foundation of laser machining,determines the machining accuracy and surface quality.It becomes much more sophisticated and dominant with a decrease in processing scale,which is systematically reviewed in this article.In general,the mechanisms of laser-induced material removal are classified into ablation,CE and atomic desorption,with a decrease in the scale from above microns to angstroms.The effects of processing parameters on both fundamental material response and machined surface quality are discussed,as well as theoretical methods to simulate and understand the underlying mechanisms.Examples at nanometric to atomic scale are provided,which demonstrate the capability of laser machining in achieving the ultimate precision and becoming a promising approach to ACSM.展开更多
This article presents the three paradigms of manufacturing advancement:Manufacturing I,craft-based manufacturing by hand,as in the Stone,Bronze,and Iron Ages,in which manufacturing precision was at the millimeter scal...This article presents the three paradigms of manufacturing advancement:Manufacturing I,craft-based manufacturing by hand,as in the Stone,Bronze,and Iron Ages,in which manufacturing precision was at the millimeter scale;ManufacturingⅡ,precision-controllable manufacturing using machinery whereby the scales of material removal,migration,and addition were reduced from millimeters to micrometers and even nanometers;and Manufacturing Ⅲ,manufacturing objectives and processes are directly focused on atoms,spanning the macro-through the micro-to the nanoscale,whereby manufacturing is based on removal,migration,and addition at the atomic scale,namely,atomic and close-to-atomic scale manufacturing(ACSM).A typical characteristic of ACSM is that energy directly impacts the atom to be removed,migrated,and added.ACSM,as the next generation of manufacturing technology,will be employed to build atomic-scale features for required functions and performance with the capacity of mass production.It will be the leading development trend in manufacturing technology and will play a significant role in the manufacturing of high-end components and future products.展开更多
Human beings have witnessed unprecedented developments since the 1760s using precision tools and manufacturing methods that have led to ever-increasing precision,from millimeter to micrometer,to single nanometer,and t...Human beings have witnessed unprecedented developments since the 1760s using precision tools and manufacturing methods that have led to ever-increasing precision,from millimeter to micrometer,to single nanometer,and to atomic levels.The modes of manufacturing have also advanced from craft-based manufacturing in the Stone,Bronze,and Iron Ages to precisioncontrollable manufacturing using automatic machinery.In the past 30 years,since the invention of the scanning tunneling microscope,humans have become capable of manipulating single atoms,laying the groundwork for the coming era of atomic and close-to-atomic scale manufacturing(ACSM).Close-to-atomic scale manufacturing includes all necessary steps to convert raw materials,components,or parts into products designed to meet the user’s specifications.The processes involved in ACSM are not only atomically precise but also remove,add,or transform work material at the atomic and close-to-atomic scales.This review discusses the history of the development of ACSM and the current state-of-the-art processes to achieve atomically precise and/or atomic-scale manufacturing.Existing and future applications of ACSM in quantum computing,molecular circuitry,and the life and material sciences are also described.To further develop ACSM,it is critical to understand the underlying mechanisms of atomic-scale and atomically precise manufacturing;develop functional devices,materials,and processes for ACSM;and promote high throughput manufacturing.展开更多
Atomic and close-to-atomic scale manufacturing is the key technology for the production of next-generation devices with atomic precision.As an important approach of mechanical processing,cutting has evolved as a poten...Atomic and close-to-atomic scale manufacturing is the key technology for the production of next-generation devices with atomic precision.As an important approach of mechanical processing,cutting has evolved as a potential candidate to generate an atomically smooth surface;thus,exploring its ultimate capability is significant.In this paper,single-crystal graphite,whose lattice structure and chemical bond property are of representation for demonstration,is selected to study the mechanism of atomic layer removal using molecular dynamics.A localized workpiece,which is dynamically updated on the basis of the tool position,is used to improve the computation efficiency.The principle and bullet points of this modeling method are first introduced,followed by a series of simulations under various undeformed chip thicknesses and tool edge radi.In addition,different potentials for the tool-workpiece interaction are tested,and the effect on the material response is presented.Based on the analysis of deformation,the number of carbon layers removed,and cutting forces,the chip formation mechanism and further understanding of the controllability of cutting at atomic and close-to-atomic scale can be achieved.展开更多
This paper presents a new approach for material removal on silicon at atomic and close-to-atomic scale assisted by photons.The corresponding mechanisms are also investigated.The proposed approach consists of two seque...This paper presents a new approach for material removal on silicon at atomic and close-to-atomic scale assisted by photons.The corresponding mechanisms are also investigated.The proposed approach consists of two sequential steps:surface modification and photon irradiation.The back bonds of silicon atoms are first weakened by the chemisorption of chlorine and then broken by photon energy,leading to the desorption of chlorinated silicon.The mechanisms of photon-induced desorption of chlorinated silicon,i.e.,SiCl_(2) and SiCl,are explained by two models:the Menzel-Gomer-Redhead(MGR)and Antoniewicz models.The desorption probability associated with the two models is numerically calculated by solving the Liouville-von Neumann equations for open quantum systems.The calculation accuracy is verified by comparison with the results in literatures in the case of the NO/Pt(111)system.The calculation method is then applied to the cases of SiCl_(2)/Si and SiCl/Si systems.The results show that the value of desorption probability first increases dramatically and then saturates to a stable value within hundreds of femtoseconds after excitation.The desorption probability shows a super-linear dependence on the lifetime of excited states.展开更多
Atomic force microscopy(AFM)-based local anodic oxidation(LAO)stands out for its high resolution,maskless operation,and simplicity.However,the role of mechanical force in LAO remains underexplored.This study addresses...Atomic force microscopy(AFM)-based local anodic oxidation(LAO)stands out for its high resolution,maskless operation,and simplicity.However,the role of mechanical force in LAO remains underexplored.This study addresses this gap by introducing an innovative experimental approach that decouples mechanical load from other variables,enabling precise control of adhesive and compressive forces during LAO.Through systematic experiments,we investigate the effect of load conditions on oxide morphology and current–voltage characteristics.Results reveal that adhesive forces promote vertical oxide growth with minimal lateral spreading,while compressive forces enhance lateral oxidation but introduce considerable variability.A high compressive force(+20 nN)combined with high bias voltages(>7 V)results in considerable current fluctuations and abrupt oxide protrusions,which are attributed to localized microdischarges and mechanical disruptions.These findings provide new insights into the interplay between mechanical forces and electrochemical processes in LAO,contributing to the development of more reliable and precise nanofabrication techniques.This study not only bridges a critical knowledge gap but also offers practical implications for optimizing AFM-based oxidation processes in semiconductor manufacturing and related fields.展开更多
Atomic force microscopy(AFM)-based electrochemical etching of a highly oriented pyrolytic graphite(HOPG)surface is studied toward the single-atomic-layer lithography of intricate patterns.Electrochemical etching is pe...Atomic force microscopy(AFM)-based electrochemical etching of a highly oriented pyrolytic graphite(HOPG)surface is studied toward the single-atomic-layer lithography of intricate patterns.Electrochemical etching is performed in the water meniscus formed between the AFM tip apex and HOPG surface due to a capillary effect under controlled high relative humid-ity(~75%)at otherwise ambient conditions.The conditions to etch nano-holes,nano-lines,and other intricate patterns are investigated.The clectrochemical reactions of HOPG etching should not generatc debris duc to the conversion of graphite to gaseous CO and CO_(2)based on etching reactions.However,debris is observed on the etched HOPG surface,and incom-plete gasification of carbon occurs during the etching process,resulting in the generation of solid intermediates.Moreover,the applied potential is of critical importance for precise etching,and the precision is also significantly influenced by the AFM tip wear.This study shows that the AFM-based electrochemical etching has the potential to remove the material in a single-atomic-layer precision.This result is likely because the etching process is based on anodic dissolution,resulting in the material removal atom by atom.展开更多
基金supported by the National Natural Science Foundation of China(Nos.52035009,52105475).
文摘With the rapid development in advanced industries,such as microelectronics and optics sectors,the functional feature size of devises/components has been decreasing from micro to nanometric,and even ACS for higher performance,smaller volume and lower energy consumption.By this time,a great many quantum structures are proposed,with not only an extreme scale of several or even single atom,but also a nearly ideal lattice structure with no material defect.It is almost no doubt that such structures play critical role in the next generation products,which shows an urgent demand for the ACSM.Laser machining is one of the most important approaches widely used in engineering and scientific research.It is high-efficient and applicable for most kinds of materials.Moreover,the processing scale covers a huge range from millimeters to nanometers,and has already touched the atomic level.Laser–material interaction mechanism,as the foundation of laser machining,determines the machining accuracy and surface quality.It becomes much more sophisticated and dominant with a decrease in processing scale,which is systematically reviewed in this article.In general,the mechanisms of laser-induced material removal are classified into ablation,CE and atomic desorption,with a decrease in the scale from above microns to angstroms.The effects of processing parameters on both fundamental material response and machined surface quality are discussed,as well as theoretical methods to simulate and understand the underlying mechanisms.Examples at nanometric to atomic scale are provided,which demonstrate the capability of laser machining in achieving the ultimate precision and becoming a promising approach to ACSM.
文摘This article presents the three paradigms of manufacturing advancement:Manufacturing I,craft-based manufacturing by hand,as in the Stone,Bronze,and Iron Ages,in which manufacturing precision was at the millimeter scale;ManufacturingⅡ,precision-controllable manufacturing using machinery whereby the scales of material removal,migration,and addition were reduced from millimeters to micrometers and even nanometers;and Manufacturing Ⅲ,manufacturing objectives and processes are directly focused on atoms,spanning the macro-through the micro-to the nanoscale,whereby manufacturing is based on removal,migration,and addition at the atomic scale,namely,atomic and close-to-atomic scale manufacturing(ACSM).A typical characteristic of ACSM is that energy directly impacts the atom to be removed,migrated,and added.ACSM,as the next generation of manufacturing technology,will be employed to build atomic-scale features for required functions and performance with the capacity of mass production.It will be the leading development trend in manufacturing technology and will play a significant role in the manufacturing of high-end components and future products.
基金The authors gratefully acknowledge the support from the National Science Foundation of China(Grant Nos.51320105009,61635008,and 61675149)and the Science Foundation Ireland(SFI)(Grant Nos.15/RP/B3208 and 18/FIP/3555).
文摘Human beings have witnessed unprecedented developments since the 1760s using precision tools and manufacturing methods that have led to ever-increasing precision,from millimeter to micrometer,to single nanometer,and to atomic levels.The modes of manufacturing have also advanced from craft-based manufacturing in the Stone,Bronze,and Iron Ages to precisioncontrollable manufacturing using automatic machinery.In the past 30 years,since the invention of the scanning tunneling microscope,humans have become capable of manipulating single atoms,laying the groundwork for the coming era of atomic and close-to-atomic scale manufacturing(ACSM).Close-to-atomic scale manufacturing includes all necessary steps to convert raw materials,components,or parts into products designed to meet the user’s specifications.The processes involved in ACSM are not only atomically precise but also remove,add,or transform work material at the atomic and close-to-atomic scales.This review discusses the history of the development of ACSM and the current state-of-the-art processes to achieve atomically precise and/or atomic-scale manufacturing.Existing and future applications of ACSM in quantum computing,molecular circuitry,and the life and material sciences are also described.To further develop ACSM,it is critical to understand the underlying mechanisms of atomic-scale and atomically precise manufacturing;develop functional devices,materials,and processes for ACSM;and promote high throughput manufacturing.
基金the Science Challenge Project(No.TZ2018006-0201-01)National Natural Science Foundation of China(Nos.52035009,61635008).
文摘Atomic and close-to-atomic scale manufacturing is the key technology for the production of next-generation devices with atomic precision.As an important approach of mechanical processing,cutting has evolved as a potential candidate to generate an atomically smooth surface;thus,exploring its ultimate capability is significant.In this paper,single-crystal graphite,whose lattice structure and chemical bond property are of representation for demonstration,is selected to study the mechanism of atomic layer removal using molecular dynamics.A localized workpiece,which is dynamically updated on the basis of the tool position,is used to improve the computation efficiency.The principle and bullet points of this modeling method are first introduced,followed by a series of simulations under various undeformed chip thicknesses and tool edge radi.In addition,different potentials for the tool-workpiece interaction are tested,and the effect on the material response is presented.Based on the analysis of deformation,the number of carbon layers removed,and cutting forces,the chip formation mechanism and further understanding of the controllability of cutting at atomic and close-to-atomic scale can be achieved.
基金This work was supported by the Science Foundation Ireland(SFI)(No.15/RP/B3208)the National Natural Science Foundation of China(NSFC)(No.52035009)。
文摘This paper presents a new approach for material removal on silicon at atomic and close-to-atomic scale assisted by photons.The corresponding mechanisms are also investigated.The proposed approach consists of two sequential steps:surface modification and photon irradiation.The back bonds of silicon atoms are first weakened by the chemisorption of chlorine and then broken by photon energy,leading to the desorption of chlorinated silicon.The mechanisms of photon-induced desorption of chlorinated silicon,i.e.,SiCl_(2) and SiCl,are explained by two models:the Menzel-Gomer-Redhead(MGR)and Antoniewicz models.The desorption probability associated with the two models is numerically calculated by solving the Liouville-von Neumann equations for open quantum systems.The calculation accuracy is verified by comparison with the results in literatures in the case of the NO/Pt(111)system.The calculation method is then applied to the cases of SiCl_(2)/Si and SiCl/Si systems.The results show that the value of desorption probability first increases dramatically and then saturates to a stable value within hundreds of femtoseconds after excitation.The desorption probability shows a super-linear dependence on the lifetime of excited states.
基金Science Foundation Ireland,Grant 22/RP-2TF/10466,Fengzhou Fang.
文摘Atomic force microscopy(AFM)-based local anodic oxidation(LAO)stands out for its high resolution,maskless operation,and simplicity.However,the role of mechanical force in LAO remains underexplored.This study addresses this gap by introducing an innovative experimental approach that decouples mechanical load from other variables,enabling precise control of adhesive and compressive forces during LAO.Through systematic experiments,we investigate the effect of load conditions on oxide morphology and current–voltage characteristics.Results reveal that adhesive forces promote vertical oxide growth with minimal lateral spreading,while compressive forces enhance lateral oxidation but introduce considerable variability.A high compressive force(+20 nN)combined with high bias voltages(>7 V)results in considerable current fluctuations and abrupt oxide protrusions,which are attributed to localized microdischarges and mechanical disruptions.These findings provide new insights into the interplay between mechanical forces and electrochemical processes in LAO,contributing to the development of more reliable and precise nanofabrication techniques.This study not only bridges a critical knowledge gap but also offers practical implications for optimizing AFM-based oxidation processes in semiconductor manufacturing and related fields.
基金The authors would like to thank the support received from the Science Foundation Ireland(SFI)(No.15/RP/B3208)‘111’project by the State Administration of Foreign Experts Affairs and the Ministry of Education of China(No.B07014)+2 种基金the National Natural Science Foundation of China(NSFC)(No.61635008)This project has also received funding from Enterprise Ireland and the European Union's Horizon 2020 Research and Inno-vation Programme under the Marie Sklodowska-Curie Grant(No.713654)from Science Foundation Ireland and the Sustainable Energy Authority of Ireland(SEAI)under the SFI Career Develop-ment Award Grant(17/CDA/4637).
文摘Atomic force microscopy(AFM)-based electrochemical etching of a highly oriented pyrolytic graphite(HOPG)surface is studied toward the single-atomic-layer lithography of intricate patterns.Electrochemical etching is performed in the water meniscus formed between the AFM tip apex and HOPG surface due to a capillary effect under controlled high relative humid-ity(~75%)at otherwise ambient conditions.The conditions to etch nano-holes,nano-lines,and other intricate patterns are investigated.The clectrochemical reactions of HOPG etching should not generatc debris duc to the conversion of graphite to gaseous CO and CO_(2)based on etching reactions.However,debris is observed on the etched HOPG surface,and incom-plete gasification of carbon occurs during the etching process,resulting in the generation of solid intermediates.Moreover,the applied potential is of critical importance for precise etching,and the precision is also significantly influenced by the AFM tip wear.This study shows that the AFM-based electrochemical etching has the potential to remove the material in a single-atomic-layer precision.This result is likely because the etching process is based on anodic dissolution,resulting in the material removal atom by atom.
