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Fundamentals of atomic and close-to-atomic scale manufacturing:a review

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International Journal of Extreme Manufacturing 2022年第1期4卷 1-20页

作者： Jian Gao Xichun Luo Fengzhou Fang Jining Sun Centre for Precision Manufacturing DMEMUniversity of StrathclydeGlasgow G11XJUnited Kingdom State Key Laboratory of Precision Measuring Technology&Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072People’s Republic of China Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland School of Mechanical Engineering Dalian University of TechnologyDalian 116024People’s Republic of China

Atomic and close-to-atomic scale manufacturing(acsm)represents techniques for manufacturing high-end products in various fields,including future-generation computing,communication,energy,and medical devices and materials.In this paper,the theoretical boundary between acsm and classical manufacturing is identified after a thorough discussion of quantum mechanics and their effects on manufacturing.The physical origins of atomic interactions and energy beams-matter interactions are revealed from the point view of quantum mechanics.The mechanisms that dominate several key acsm processes are introduced,and a current numerical study on these processes is reviewed.A comparison of current acsm processes is performed in terms of dominant interactions,representative processes,resolution and modelling methods.Future fundamental research is proposed for establishing new approaches for modelling acsm,material selection or preparation and control of manufacturing tools and environments.This paper is by no means comprehensive but provides a starting point for further systematic investigation of acsm fundamentals to support and accelerate its industrial scale implementation in the near future.

关键词： manufacturing acsm quantum mechanics first-principles atomic interaction energy-matter interaction mechanisms

Isotropic Tuning of Electrochemical Etching forthe Nanometric Finishing of Metals

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Nanomanufacturing and Metrology 2022年第3期5卷 283-296页

作者： Rong Yi Zejin Zhan Hui Deng Department of Mechanical and Energy Engineering Southern University of Science and TechnologyNo.1088Xueyuan RoadShenzhen 518055GuangdongChina

Isotropic etching polishing(IEP)based on the merging of isotropic etch pits has been proposed as a generic metal finishing approach.In this work,the tuning of the etching isotropy of various metals,which is the key to realizing the finishing effect of IEP,is studied by theoretical analysis and etching experiments.The isotropic etching of various metals can be realized through mass transfer polarization by adjusting the electrochemical parameters.The addition of sulfuric acid in the electrolyte is the most effective for tuning the isotropy of electrochemical etching.It can decrease the diffusion coefficient of metal ions,thereby increasing the resistance of mass transfer and transforming the electrochemical dissolution of metal into mass transfer polarization.In this study,the atomic and close-to-atomic scale surface finishing of various metals and alloys has been successfully achieved through isotropic etching.After etching at a current of 1.5 A for 3 min,the surface Sa roughness of TA2 is drastically reduced from 242 to 3.98 nm.After etching for 1 min at a current of 3 A,the surface Sa roughness of pure tungsten,NiTi,and CoCrNi decreases from 9.33,76.4,and 37.6 nm,respectively,to 1.16,2.01,and 2.51 nm,respectively.

关键词： acsm Metal finishing Isotropic etching polishing Electrochemical polishing

Cutting of Graphite at Atomic and Close-to-Atomic Scale Using Flexible Enhanced Molecular Dynamics

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Nanomanufacturing and Metrology 2022年第3期5卷 240-249页

作者： Jinshi Wang Fengzhou Fang Luan Li State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072China Centreof Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland

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.

关键词： Atomic and close-to-atomic scale Cutting Enhanced molecular dynamics Graphite acsm

北京市典型区域大气亚微米颗粒物理化特性及其来源

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中国环境科学 2022年第8期42卷 3522-3535页

作者：韩力慧时瑞芳崔建硕杨雪梅王海燕程水源北京工业大学环境与生命学部区域大气复合污染防治北京市重点实验室北京100124

本研究采用Aerodyne气溶胶化学组成在线监测质谱仪acsm,于2019年春季、夏季后期、秋季和冬季典型代表月对北京市东南城区非难熔亚微米颗粒物NR-PM_(1)进行了实时监测与分析,研究了NR-PM_(1)及其物种在不同时段,特别是霾污染期间的演变特... 详细信息

本研究采用Aerodyne气溶胶化学组成在线监测质谱仪acsm,于2019年春季、夏季后期、秋季和冬季典型代表月对北京市东南城区非难熔亚微米颗粒物NR-PM_(1)进行了实时监测与分析,研究了NR-PM_(1)及其物种在不同时段,特别是霾污染期间的演变特征,以及4个季节有机物的来源.结果表明,整个研究期间NR-PM_(1)的平均浓度为22.06μg/m^(3),其季节变化呈现出春季>冬季>秋季>夏季后期的特征.整个研究期间,Org(有机物)的平均浓度为7.12μg/m^(3),占NR-PM_(1)的32.30%;NO_(3)^(-)和SO_(4)^(2-)的平均浓度分别为5.91和6.20μg/m^(3),分别占NR-PM_(1)的26.80%和28.12%;而NH_(4)^(+)和Cl^(-)的平均质量浓度和质量百分数均较低.所有物种呈现出Org>SO_(4)^(2-)~NO_(3)^(-)>NH_(4)^(+)>Cl^(-)的特征.清洁天NR-PM_(1)以Org为主要特征,各季节所有物种的日变化均较小,而霾污染天NR-PM_(1)以二次无机物种为主要特征,不同季节各物种表现出不同的日变化特征.OA(有机气溶胶)在不同季节解析出的物种有所不同.一次有机气溶胶POA对OA的贡献随春夏秋冬逐渐升高,而二次有机气溶胶SOA则随之逐渐降低.

关键词： acsm NR-PM1 有机气溶胶二次无机组分来源

Socio-cultural features and help-seeking preferences for leprosy and tuberculosis: a cultural epidemiological study in a tribal district of Maharashtra, India

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Infectious Diseases of Poverty 2015年第1期4卷 257-270页

作者： Amar Prakash Maske Pravin Arun Sawant Saju Joseph Uma Satish Mahajan Abhay Machindra Kudale The Maharashtra Association of Anthropological Sciences Centre for Health Research and Development(MAAS-CHRD)201Akanksha ResidencyB-WingSecond FloorNear Shivaji StatueAundh GaonPune 411007MaharashtraIndia Savitribai Phule Pune University GaneshkhindPuneMaharashtra 411007India

Background:India is a major contributor to the global burden of leprosy and tuberculosis(TB),which adversely affects the poorest tribal communities.Despite prioritisation by disease control programmes,programme performance for leprosy and TB in tribal communities continues to be a challenge.In addition to access to services and infrastructural limitations,socio-cultural concepts of illness causation and related help seeking(HS)rooted in distinct features of tribal culture need to be addressed to improve programme outcomes.Methods:A cultural epidemiological survey of leprosy and TB patients was carried out using a locally adapted,semi-structured explanatory model interviews.A total of 100 leprosy and 50 TB patients registered for treatment at government health facilities were selected randomly from tribal dominant blocks of the Thane district,Maharashtra state.The perceived causes(PCs)of leprosy and TB in patients were compared based on prominence categories.The relationship between PCs as predictors,and disease conditions and HS preferences as outcome variables were assessed using multivariate logistic regression.Results:In the multivariate logistic regression model with disease conditions as outcome variables,TB patients were significantly more likely to report PCs in the categories of ingestion;health,illness and injury;and traditional,cultural and supernatural.Tuberculosis patients more frequently first sought help from private facilities as compared to leprosy patients who preferred government health facilities.In a combined analysis of leprosy and TB patients employing multivariate logistic regression,it was found that patients who reported PCs in the environmental and contact-related categories were more likely to visit traditional rather than non-traditional practitioners.In another multivariate combined model,it was found that patients who reported PCs in the traditional,cultural and supernatural category were significantly more likely to visit private rather than public health facilities.Conclusion:Cultu

关键词： Socio-cultural features Help seeking Leprosy Tuberculosis Tribal Cultural epidemiology acsm IEC India

Laser machining fundamentals:micro,nano,atomic and close-to-atomic scales

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International Journal of Extreme Manufacturing 2023年第1期5卷 125-151页

作者： Jinshi Wang Fengzhou Fang Haojie An Shan Wu Huimin Qi Yuexuan Cai Guanyu Guo State Key Laboratory of Precision Measuring Technology&Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072People’s Republic of China Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin4Ireland

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.

关键词： laser machining mechanism atomic and close-to-atomic scale manufacturing acsm manufacturing III

Study on Mechanisms of Photon-Induced Material Removal on Silicon at Atomic and Close-to-Atomic Scale

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Nanomanufacturing and Metrology 2021年第4期4卷 216-225页

作者： Peizhi Wang Jinshi Wang Fengzhou Fang Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072China

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.

关键词： Atomic and close-to-atomic scale manufacturing acsm Surface chlorination Photon-induced desorption Silicon

Crystallographic orientation effect on cutting-based single atomic layer removal

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Frontiers of Mechanical Engineering 2020年第4期15卷 631-644页

作者： Wenkun XIE Fengzhou FANG Centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublin 4Ireland State Key Laboratory of Precision Measuring Technology and Instruments Centre of Micro/Nano Manufacturing Technology(MNMT)Tianjin UniversityTianjin 300072China

The ever-increasing requirements for the scalable manufacturing of atomic-scale devices emphasize the significance of developing atomic-scale manufacturing technology. The mechanism of a single atomic layer removal in cutting is the key basic theoretical foundation for atomic-scale mechanical cutting. Material anisotropy is among the key decisive factors that could not be neglected in cutting at such a scale. In the present study, the crystallographic orientation effect on the cutting-based single atomic layer removal of monocrystalline copper is investigated by molecular dynamics simulation. When undeformed chip thickness is in the atomic scale, two kinds of single atomic layer removal mechanisms exist in cutting-based single atomic layer removal, namely, dislocation motion and extrusion, due to the differing atomic structures on different crystallographic planes. On close-packed crystallographic plane, the material removal is dominated by the shear stress-driven dislocation motion, whereas on non-close packed crystallographic planes, extrusion-dominated material removal dominates. To obtain an atomic, defect-free processed surface, the cutting needs to be conducted on the close-packed crystallographic planes of monocrystalline copper.

关键词： acsm single atomic layer removal mecha-nism crystallographic orientation effect mechanical cutting Manufacturing III

Periodic energy decomposition analysis for electronic transport studies as a tool for atomic scale device manufacturing

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International Journal of Extreme Manufacturing 2020年第1期2卷 164-172页

作者： Paven Thomas Mathew Fengzhou Fang Centre of Micro/Nano Manufacturing Technology MNMT-DublinUniversity College DublinIreland State Key Laboratory of Precision Measuring Technology and Instruments Centre of Micro/Nano Manufacturing TechnologyMNMTTianjin UniversityPeople’s Republic of China

Atomic scale manufacturing is a necessity of the future to develop atomic scale devices with high precision.A different perspective of the quantum realm,which includes the tunnelling effect,leakage current at the atomic-scale,Coulomb blockade and Kondo effect,is inevitable for the fabrication and hence,the mass production of these devices.For these atomic-scale device development,molecular level devices must be fabricated.Proper theoretical studies could be an aid towards the experimental realities.Electronic transport studies are the basis to realise and interpret the problems happening at this minute scale.Keeping these in mind,we present a periodic energy decomposition analysis(pEDA)of two potential candidates for moletronics:phthalocyanines and porphyrins,by placing them over gold substrate cleaved at the(111)plane to study the adsorption and interaction at the interface and then,to study their application as a channel between two electrodes,thereby,providing a link between pEDA and electronic transport studies.pEDA provides information regarding the bond strength and the contribution of electrostatic energy,Pauli’s energy,orbital energy and the orbital interactions.Combining this analysis with electronic transport studies can provide novel directions for atomic/close-toatomic-scale manufacturing(acsm).Literature survey shows that this is the first work which establishes a link between pEDA and electronic transport studies and a detailed pEDA study on the above stated molecules.The results show that among the molecules studied,porphyrins are more adsorbable over gold substrate and conducting across a molecular junction than phthalocyanines,even though both molecules show a similarity in adsorption and conduction when a terminal thiol linker is attached.A further observation establishes the importance of attractive terms,which includes interaction,orbital and electrostatic energies,in correlating the pEDA study with the transport properties.By progressing this research,further developments could be possible in

关键词： phthalocyanine porphyrin potential energy decomposition analysis potential energy surface scan moletronics acsm Manufacturing III