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right20397700CHAPTER 3 Synthesis of nanomaterials 3

right20397700CHAPTER 3
Synthesis of nanomaterials
3.1 Introduction
Fabrication approaches for the synthesis of nanomaterials can be subdivided into two groups, namely, top-down and bottom-up approaches: The top-down approach entails the chopping down of bulk material to small pieces of nanomaterial. This approach mainly uses techniques to selectively remove micro-scale structures from the bulk material. However, this approach has some challenges in creating uniform nanoparticles and it introduces internal stress and defects with contamination, making this approach unfitting for the synthesis of very small materials with uniform shape ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “abstract” : “Materials scientists are conducting research to develop novel materials with better properties, more functionality and lower cost than the existing one. Several physical, chemical methods have been developed to enhance the performance of nanomaterials displaying improved properties with the aim to have a better control over the particle size, distribution 1. 3.1 Methods to Synthesis of Nanomaterials In general, top-down and bottom-up are the two main approaches for nanomaterials synthesis. a. Top-down: size reduction from bulk materials. b. Bottom-up: material synthesis from atomic level. Top-down routes are included in the typical solid u2013state processing of the materials. This route is based with the bulk material and makes it smaller, thus breaking up larger particles by the use of physical processes like crushing, milling or grinding. Usually this route is not suitable for preparing uniformly shaped materials, and it is very difficult to realize very small particles even with high energy consumption. The biggest problem with top-down approach is the imperfection of the surface structure. Such imperfection would have a significant impact on physical properties and surface chemistry of nanostructures and nanomaterials. It is well known that the conventional top-down technique can cause significant crystallographic damage to the processed patterns.”, “id” : “ITEM-1”, “issued” : { “date-parts” : “0” }, “page” : “64-93”, “title” : “Copy of Introduction to synthesis of nanomaterials”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=608514c0-9d8b-4cba-96e5-b58e3ded1eec” } , “mendeley” : { “formattedCitation” : “1”, “plainTextFormattedCitation” : “1”, “previouslyFormattedCitation” : “1” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }1. The bottom-up approach, on the other hand, refers to the build-up of material from a single atom or molecular precursors to large nanostructures of certain shape or size using physical or chemical forces ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “:10.2777/76945”, “ISBN” : “9789279214370”, “ISSN” : “01004042”, “abstract” : “This compendium has been specifically developed to provide the educational communities with relevant, accurate and updated materials to inform, motivate and inspire young people to know more about nanosciences and nanotechnologies concepts and applications. It has been developed within the context of the European research project Nanoyou, and it has been enriched by the authors with numerous and multifaceted inputs, reflections and insights on societal issues, also provided by the European project TimeforNano. The outcomes from all these efforts have been integrated into a comprehensive and fully referenced book to present a single, balanced compendium about these disciplines. Theory, application, experiments and discussion on the ethical, societal and safety aspects are organised in self-contained modules that offer increased flexibility throughout the development of the course. Also, a case study approach provides educators and teachers with practical applications and examples to discuss in class, supported by online tutor web portals to enable participating in virtual dialogues, experiments and games. The lessons, discussions on applications and hands-on experiments presented in this book have been tested and enriched from 2010 to 2011 by hundreds of teachers, professors and educators from about one thousand schools in 20 countries in Europe and beyond, involving about 40.000 students. This stimulating, challenging and enriching experience enabled us to produce the far-reaching, broad-ranging and inclusive book you have in your hands.”, “author” : { “dropping-particle” : “”, “family” : “Sutherland”, “given” : “Luisa Filipponi and Duncan”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “European Commission”, “id” : “ITEM-1”, “issued” : { “date-parts” : “2012” }, “number-of-pages” : “406”, “title” : “Nanotechnologies: Principles, Applications, Implications and Hands-on Activities”, “type” : “book” }, “uris” : “http://www.mendeley.com/documents/?uuid=cc6c1acf-a3be-4b5b-a656-c9d935f0abeb” } , “mendeley” : { “formattedCitation” : “2”, “plainTextFormattedCitation” : “2”, “previouslyFormattedCitation” : “2” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }2. Quantum effect is of high importance in tailoring new properties of nanomaterial, that are different from the bulk material. Nanoparticles growth mechanism determines things such as distribution function of nanoparticles on size, and physical-chemical properties of nanoparticles medium ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.13005/ojc/300456”, “ISBN” : “0970020X\r22315039”, “ISSN” : “22315039”, “abstract” : “The synthesis of metallic nanoparticles is an active area of academic and, more significantly, applied research in nanotechnology. Several methods have been introduced for the synthesis of these materials. The techniques for synthesizing aluminum nanoparticles can be divided into solid-phase, liquid-phase and gas-phase processes. The solid-phase techniques include mechanical ball milling and mechanochemical, the liquid-phase techniques include laser ablation, exploding wire, solution reduction, and decomposition process, whereas the gas-phase processes include gas evaporation, exploding wire, and laser ablation process. This study is an attempt to present an overview of Al nanoparticles preparation by various methods.”, “author” : { “dropping-particle” : “”, “family” : “Ghorbani”, “given” : “Hamid Reza”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Oriental Journal of Chemistry”, “id” : “ITEM-1”, “issue” : “4”, “issued” : { “date-parts” : “2014” }, “page” : “1941-1949”, “title” : “A review of methods for synthesis of Al nanoparticles”, “type” : “article-journal”, “volume” : “30” }, “uris” : “http://www.mendeley.com/documents/?uuid=be0e15db-b155-4de3-9949-4ddfb55fdc74” } , “mendeley” : { “formattedCitation” : “3”, “plainTextFormattedCitation” : “3”, “previouslyFormattedCitation” : “3” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }3. Nanoparticle growth depends on various conditions (i.e temperature, concentration, etc.). These conditions can differ according to the synthesis method of nanoparticles. CdS nanoparticles have been previously prepared using chemical precipitation method ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1016/j.jpcs.2009.05.024”, “ISSN” : “00223697”, “abstract” : “In the present study we have synthesized CdS semiconducting quantum dots by the chemical precipitation method using Thioglycerol as the capping agent. X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) are employed to characterize the size, morphology and crystalline structure of the as-prepared material. The synthesized QPs have a mixture of cubical and hexagonal crystal symmetry with 12 nm average diameter. Ultraviolet-visible (UV-vis) absorption spectroscopy is used to calculate the band gap of the material and blue shift in absorption edge. Confinement of the optical phonon modes in the QPs is studied by Raman spectroscopy, while FTIR for identification of chemical bonds in the nanomaterial. Multiple cadmium and sulphur defects were observed by employing the photoluminescence (PL) method. u00a9 2009 Elsevier Ltd. All rights reserved.”, “author” : { “dropping-particle” : “”, “family” : “Singh”, “given” : “Vineet”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Chauhan”, “given” : “Pratima”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Journal of Physics and Chemistry of Solids”, “id” : “ITEM-1”, “issue” : “7”, “issued” : { “date-parts” : “2009” }, “page” : “1074-1079”, “title” : “Structural and optical characterization of CdS nanoparticles prepared by chemical precipitation method”, “type” : “article-journal”, “volume” : “70” }, “uris” : “http://www.mendeley.com/documents/?uuid=4eaec770-9dd8-4e9f-837e-e026ba135740” } , “mendeley” : { “formattedCitation” : “4”, “plainTextFormattedCitation” : “4”, “previouslyFormattedCitation” : “4” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }4, solvothermal method ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1080/17458080802654486”, “ISSN” : “1745-8080”, “author” : { “dropping-particle” : “”, “family” : “Phuruangrat”, “given” : “Anukorn”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Thongtem”, “given” : “Titipun”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Thongtem”, “given” : “Somchai”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Journal of Experimental Nanoscience”, “id” : “ITEM-1”, “issue” : “1”, “issued” : { “date-parts” : “2009”, “3”, “1” }, “note” : “doi: 10.1080/17458080802654486”, “page” : “47-54”, “publisher” : “Taylor & Francis”, “title” : “Characterisation of one-dimensional CdS nanorods synthesised by solvothermal method”, “type” : “article-journal”, “volume” : “4” }, “uris” : “http://www.mendeley.com/documents/?uuid=02e5bf7b-a63d-403e-83cb-ac87a43fa391” } , “mendeley” : { “formattedCitation” : “5”, “plainTextFormattedCitation” : “5”, “previouslyFormattedCitation” : “5” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }5, laser ablation method ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1016/j.apsusc.2005.03.004”, “ISSN” : “01694332”, “abstract” : “In this work colloidal quantum dots (QDs) of GaAs and CdS semiconductors have been formed by laser ablation in the liquid media. The pulsed passive mode-locked Nd:YAG laser at 1064 nm wavelength with pulse duration u03c4imp= 33 ps and energy 30 mJ was used. The luminescence of the colloidal QDs was excited by irradiation at 355 nm, the third harmonic of the Nd:YAG laser. The optical absorption and the photoluminescence spectra of the GaAs and CdS colloidal QDs have been investigated. The large blue shift of the photoluminescence, connected to size effects, was evaluated. The location of the maximum of luminescence spectra at the wavelengths 405 nm (CdS) and 420 nm (GaAs) give calculated sizes of QDs of 2-3 nm. u00a9 2005 Elsevier B.V. All rights reserved.”, “author” : { “dropping-particle” : “”, “family” : “Lalayan”, “given” : “A. A.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Applied Surface Science”, “id” : “ITEM-1”, “issue” : “1-4”, “issued” : { “date-parts” : “2005” }, “page” : “209-212”, “title” : “Formation of colloidal GaAs and CdS quantum dots by laser ablation in liquid media”, “type” : “article-journal”, “volume” : “248” }, “uris” : “http://www.mendeley.com/documents/?uuid=54eca046-02d1-40c9-b9cb-b892017bfc48” } , “mendeley” : { “formattedCitation” : “6”, “plainTextFormattedCitation” : “6”, “previouslyFormattedCitation” : “6” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }6, hydrothermal method ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1007/s11458-007-0020-x”, “ISBN” : “1001-4861”, “ISSN” : “16733495”, “abstract” : “CdS nanoparticles with good crystallinity were prepared by hydrothermal method in microemulsion composed of polyoxyethylene laurylether/water/ cyclohexane/butanol. The structure and the size of the CdS nanoparticles were analyzed by TEM and XRD. The UV-Vis optical absorption of the samples was also investigated. The results show that hydrothermal treatment is an effective method to prepare CdS nanoparticles of hexagonal structure at lower temperature. The particles were in dimensional uniformity. The diameter of the CdS nanoparticles decreased with the increase of the molar ratio of water to surfactant. The minimum diameter of the CdS nanoparticles prepared in this work was about 10 nm. Obvious blue shift appeared in the UV-Vis absorption spectra. u00a9 2007 Higher Education Press and Springer-Verlag.”, “author” : { “dropping-particle” : “”, “family” : “Zang”, “given” : “Jinxin”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Zhao”, “given” : “Gaoling”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Han”, “given” : “Gaorong”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Frontiers of Chemistry in China”, “id” : “ITEM-1”, “issue” : “1”, “issued” : { “date-parts” : “2007” }, “page” : “98-101”, “title” : “Preparation of CdS nanoparticles by hydrothermal method in microemulsion”, “type” : “article-journal”, “volume” : “2” }, “uris” : “http://www.mendeley.com/documents/?uuid=75893d94-082a-4ca9-8b3c-49c78de8f070” } , “mendeley” : { “formattedCitation” : “7”, “plainTextFormattedCitation” : “7”, “previouslyFormattedCitation” : “7” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }7, photochemical method ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1088/0957-4484/16/2/027”, “ISSN” : “0957-4484”, “author” : { “dropping-particle” : “”, “family” : “Marandi”, “given” : “M”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Taghavinia”, “given” : “N”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “zad”, “given” : “A Iraji”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Mahdavi”, “given” : “S M”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Nanotechnology”, “id” : “ITEM-1”, “issue” : “2”, “issued” : { “date-parts” : “2005”, “2”, “1” }, “page” : “334-338”, “title” : “A photochemical method for controlling the size of CdS nanoparticles”, “type” : “article-journal”, “volume” : “16” }, “uris” : “http://www.mendeley.com/documents/?uuid=3fbd63ce-b200-38e1-aa0a-8594e968a4b3” } , “mendeley” : { “formattedCitation” : “8”, “plainTextFormattedCitation” : “8”, “previouslyFormattedCitation” : “8” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }8, one-pot synthesis method ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1088/0957-4484/17/3/039”, “ISSN” : “0957-4484”, “author” : { “dropping-particle” : “”, “family” : “Tong”, “given” : “Hua”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Zhu”, “given” : “Ying-Jie”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Nanotechnology”, “id” : “ITEM-1”, “issue” : “3”, “issued” : { “date-parts” : “2006”, “2”, “14” }, “page” : “845-851”, “title” : “Synthesis of CdS nanocrystals based on low-temperature thermolysis of one single-source organometallic precursor”, “type” : “article-journal”, “volume” : “17” }, “uris” : “http://www.mendeley.com/documents/?uuid=bcc58804-a214-39b9-af89-e6176282e830” } , “mendeley” : { “formattedCitation” : “9”, “plainTextFormattedCitation” : “9”, “previouslyFormattedCitation” : “9” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }9, mesoporous copolymer template method ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1590/S0103-97332006000300052”, “ISSN” : “0103-9733”, “author” : { “dropping-particle” : “”, “family” : “Monte”, “given” : “A. F. G.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Dantas”, “given” : “N. O.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Morais”, “given” : “P. C.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Rabelo”, “given” : “D.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Brazilian Journal of Physics”, “id” : “ITEM-1”, “issue” : “2a”, “issued” : { “date-parts” : “2006”, “6” }, “page” : “427-429”, “publisher” : “Sociedade Brasileira de Física”, “title” : “Synthesis and characterisation of CdS nanoparticles in mesoporous copolymer template”, “type” : “article-journal”, “volume” : “36” }, “uris” : “http://www.mendeley.com/documents/?uuid=a49bce08-4fbe-31cb-a45f-9fe546d96360” } , “mendeley” : { “formattedCitation” : “10”, “plainTextFormattedCitation” : “10”, “previouslyFormattedCitation” : “10” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }10, and more. This work employs the bottom-up approach in the synthesis of cadmium sulfide nanoparticles and the co-loading of gold nanoparticles on the surface.

3.2 Bottom-up approach
The bottom-up approach arranges the basic building blocks such as atoms or molecules into large nanostructures using chemical or physical forces. This method generally has an advantage in the preparation of most nanoscale structures with the ability to generate a uniform size, shape, and distribution ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1007/978-3-319-56979-6”, “ISBN” : “9783319569796”, “abstract” : “u00a9 Springer International Publishing AG 2018. All rights reserved. This book covers diverse areas in which nanoscience and nanotechnology have led to significant technological advances and practical applications, with special emphasis on novel types of nanomaterials and their applicability into a new generation of nano- and micro-devices. Different nanomaterials are reviewed with a focus on several practical application areas and their commercial utilization. Production technologies of nanomaterials are presented as one of the challenges today. Sectors where nanotechnology has already significantly contributed are presented, along with specific nanotechnology solutions: energy related sectors, NEMS/MEMS, micro power generators, spintronics and healthcare. The basic properties and applications of nanostructured thermoelectric materials, ferroelectric and piezoelectric nanomaterials are reviewed. Examples of several developed thin-film thermogenerators are shown. A review of existing solutions and developing challenges are given regarding sustainable energy production, photovoltaics, solar cells, hydrogen economy and improved classes of batteries as contributions to green products and circular economy. Novel, highly promising areas in nanotechnology, are shown, such as voltage-driven nano-spintronics. Recent advances in friction characterisation at the nano level are described. Several proven nanomaterials have been reviewed pertaining to biomedicine. The use of nanomaterials in ophthalmology and cosmetic industry are reviewed, and the potential for silver nanoparticles and iron-based nanomaterials in biomedicine, also with recognised challenges and possible threats of non-controlled use of nanomaterials. This work is the result of joint efforts of different companies, academic, and research institutions participating in WIMB Tempus project, 543898-TEMPUS-1-2013-1-ES-TEMPUS-JPHES, “Development of Sustainable Interrelations between Education, Research and Innovation at WBC Universities in Nanotechnologies and Advanced Materials where Innovation Means Business”, co-funded by the Tempus Programme of the European Union.”, “author” : { “dropping-particle” : “”, “family” : “Brabazon”, “given” : “Dermot”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Pellicer”, “given” : “Eva”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Zivic”, “given” : “Fatima”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Sort”, “given” : “Jordi”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Baru00f3”, “given” : “Maria Dolors”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Grujovic”, “given” : “Nenad”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Choy”, “given” : “Kwang Leong”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Commercialization of Nanotechnologies-A Case Study Approach”, “id” : “ITEM-1”, “issued” : { “date-parts” : “2017” }, “page” : “1-315”, “title” : “Commercialization of nanotechnologies-A case study approach”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=f4b5ba54-8165-41fe-9f5f-5c84aa350b6b” } , “mendeley” : { “formattedCitation” : “11”, “plainTextFormattedCitation” : “11”, “previouslyFormattedCitation” : “11” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }11. It effectively covers chemical synthesis and precisely controlled the reaction to inhibit further particle growth. Synthesis of nanoclusters in this approach can either be by gas-phase or liquid-phase methods. The gas-phase method is mostly used in thin film synthesis and entails the carrying of metal vapour by a gas medium. Some involved processes include physical vapour deposition (PVD), chemical vapour deposition (CVD), and atomic layer deposition (ALD). This ability to build from scratch allows for tuning of nanomaterials of certain sizes, structure, shape, and composition ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1007/978-3-319-56979-6”, “ISBN” : “9783319569796”, “author” : { “dropping-particle” : “”, “family” : “Su”, “given” : “Shei Sia”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Chang”, “given” : “Isaac”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “0” }, “title” : “Review of Production Routes of Nanomaterials”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=a683fac0-9569-4ffa-a5e4-6d1c74f3dbb1” } , “mendeley” : { “formattedCitation” : “12”, “plainTextFormattedCitation” : “12”, “previouslyFormattedCitation” : “12” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }12. Liquid phase processes, make use of surface forces to construct nanoscale particles and structures. The involved processes in this phase include chemical precipitation, sol-gel methods, and methods relying on self-assembly.
3.3 Liquid phase synthesis
Liquid phase synthesis also is known as wet chemical method is nanoparticles synthesis approaches mostly used in industries. A usual liquid phase synthesis involves mixing solution of different ions with well-defined quantities and subjected it to controlled heat, temperature and pressure to promote the formation of insoluble nanoparticles, which precipitates out of the solution. High temperature, expensive energy source or high pressure are not required in this process making it more attractive. This phase synthesis also allows more careful control of the stoichiometry composition of the end products and the nanoparticles synthesized can be stabilized or functionalized through the synthesis process ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1007/978-3-319-56979-6”, “ISBN” : “9783319569796”, “author” : { “dropping-particle” : “”, “family” : “Su”, “given” : “Shei Sia”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Chang”, “given” : “Isaac”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “0” }, “title” : “Review of Production Routes of Nanomaterials”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=a683fac0-9569-4ffa-a5e4-6d1c74f3dbb1” } , “mendeley” : { “formattedCitation” : “12”, “plainTextFormattedCitation” : “12”, “previouslyFormattedCitation” : “12” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }12. Few of the techniques involved in this process are (i) Chemical Precipitation, (ii) Hydrothermal Method, and (iii) Sol-Gel method.

3.3.1 Chemical precipitation
This is one of the various wet chemical synthesis techniques that are mostly adopted as a result of their simplicity, versatility, cost-effectiveness and the fact that they can be easily synthesized in large scales for the industry. This technique can be carried out at low temperatures, resulting in bottom-up growth of nanoparticles with varying size distribution controlled with capping reagents. Bottom-up manufacturing involves building up of the atom or molecular constituents. In chemical precipitation, the fractional precipitation of a specified ion in a solution results in the precipitation not only of the target ion but also of other ions existing in the solution ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “author” : { “dropping-particle” : “”, “family” : “Chauhan”, “given” : “Ruby”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Kumar”, “given” : “Ashavani”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Chaudhary”, “given” : “Ram Pal”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Education”, “given” : “Technology”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issue” : “5”, “issued” : { “date-parts” : “2010” }, “page” : “378-385”, “title” : “Synthesis and characterization of silver doped ZnO nanoparticles”, “type” : “article-journal”, “volume” : “2” }, “uris” : “http://www.mendeley.com/documents/?uuid=7198e95b-8a76-442f-b7c0-37fe2e38dc1c” } , “mendeley” : { “formattedCitation” : “13”, “plainTextFormattedCitation” : “13”, “previouslyFormattedCitation” : “13” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }13. During the precipitation process from the liquid phase, capping reagents are added during or shortly after precipitation. These interfere with the nucleating and growing particle to avoid agglomeration and to control size ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1002/aoc.169”, “author” : { “dropping-particle” : “”, “family” : “Schmidt”, “given” : “Helmut”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “2001” }, “page” : “331-343”, “title” : “Nanoparticles by chemical synthesis , processing to materials and innovative”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=ab4e5923-4a38-4f6b-b45b-c6c888280808” } , “mendeley” : { “formattedCitation” : “14”, “plainTextFormattedCitation” : “14”, “previouslyFormattedCitation” : “14” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }14. However, capping reagents are not always desirable for many applications that require luminescence. The efficiency is hindered by surfactants molecules that are covalent with the surface atoms of the nanoparticles, causing photoluminescence quenching ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1039/b9nr00070d”, “ISBN” : “2040-3372 (Electronic)\r2040-3364 (Linking)”, “ISSN” : “2040-3372”, “PMID” : “20648377”, “abstract” : “In this study, we have monitored the formation of CdS and HgS nanoparticles (NPs) using a precipitation method in the presence of surface-active agents. Three surfactants were tested to analyze the dependence of various parameters such as size, growth rate, photoluminescence (PL) emission and polydispersity of NPs on surfactant structure. Optical absorption spectroscopy was mainly used to estimate the optical bandgap and the size of NPs. The surfactant-induced quenching of PL intensity was found to be consistent with the different tendencies of the surfactants to act as Lewis acids towards these surfaces. The time-evolution of the absorbance suggested that the nucleation and growth rates markedly vary in a first-order fashion w.r.t. Cd(2+) and Hg(2+) salt concentration in excess of sulfide ions. The differences in the stabilization ability of the surfactants are discussed in reference to their structure-dependent adsorption behavior onto the particles. The comparative aspects of the different properties of CdS and HgS NPs prepared with identical methodology are presented in terms of metal cation-surfactant interactions. Changes in UV-vis and PL spectra during nucleation and growth of NPs were used to establish the possible mechanisms for the adsorption of surfactant molecules on the particle surface to restrict the unlimited growth.”, “author” : { “dropping-particle” : “”, “family” : “Mehta”, “given” : “S K”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Kumar”, “given” : “Sanjay”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Chaudhary”, “given” : “Savita”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Bhasin”, “given” : “K K”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Nanoscale”, “id” : “ITEM-1”, “issue” : “1”, “issued” : { “date-parts” : “2010” }, “page” : “145-52”, “title” : “Nucleation and growth of surfactant-passivated CdS and HgS nanoparticles: Time-dependent absorption and luminescence profiles.”, “type” : “article-journal”, “volume” : “2” }, “uris” : “http://www.mendeley.com/documents/?uuid=1d5cdae6-82a4-45e0-97d3-ce6477fe5427” } , “mendeley” : { “formattedCitation” : “15”, “plainTextFormattedCitation” : “15”, “previouslyFormattedCitation” : “15” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }15. For example, for organic photovoltaic hybrid solar applications, where charge transfer between nanoparticles and conjugated polymer are required, the surfactant may cause hindrance in the charge transfer ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “author” : { “dropping-particle” : “”, “family” : “Qasim”, “given” : “Maleeha”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Akram”, “given” : “Zain”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Riaz”, “given” : “Saira”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Naseem”, “given” : “Shahzad”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issue” : “Lu 2011”, “issued” : { “date-parts” : “2012” }, “page” : “1-10”, “title” : “Synthesis and Characterization of CdS Ink Comprised of Nanoparticles”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=99e96c67-f35e-403e-90ac-27eff3a9afb2” } , “mendeley” : { “formattedCitation” : “16”, “plainTextFormattedCitation” : “16”, “previouslyFormattedCitation” : “16” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }16.

3.3.2 Preparation of CdS nanoparticles
Five cadmium sulphide (CdS) nanoparticles were synthesized with wet chemical synthesis technique, chemical precipitation using thioglycerol (C3H8O2S) (TG) capping reagent to control the particle size. All the reactions were carried out at room temperature and pressure. Cadmium chloride (CdCl2) and sodium sulphide (Na2S) were used as starting material, acting as a source of Cd and S ions respectively. Double distilled water was added as a solvent with varying TG concentrations controlling the growth. Initially, 0.1 M CdCl2 and 0.1 M Na2S were added in 50 mL of double distilled water separately with vigorous magnetic stirring ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1016/j.matchar.2010.10.009”, “ISSN” : “10445803”, “abstract” : “Size tunability of thioglycerol capped cadmium sulphide nanoparticles has been achieved by controlling the capping reagent concentration as well as annealing temperature through chemical precipitation method. Optical and structural properties of CdS nanoparticles were studied through UV-Vis absorption, X-ray diffraction, energy dispersive X-ray, high resolution transmission electron microscopy, Raman and photoluminescence spectroscopy. Synthesis at 0.6 ml thioglycerol concentration produces stable nanoparticles of smallest size nearly 3 u00b1 0.5 nm having narrow size distribution, high photoluminescence intensity and lower crystallinity. Annealing improves the crystallinity and reduces the defects levels. The attachment of particles, existence of intrinsic stacking faults, extrinsic stacking faults, twin boundaries, interface dislocations as well as clear lattice fringes in high resolution transmission electron microscopy images are also discussed. u00a9 2010 Elsevier Inc. All rights reserved.”, “author” : { “dropping-particle” : “”, “family” : “Singh”, “given” : “Vineet”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Sharma”, “given” : “P. K.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Chauhan”, “given” : “Pratima”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Materials Characterization”, “id” : “ITEM-1”, “issue” : “1”, “issued” : { “date-parts” : “2011” }, “page” : “43-52”, “title” : “Synthesis of CdS nanoparticles with enhanced optical properties”, “type” : “article-journal”, “volume” : “62” }, “uris” : “http://www.mendeley.com/documents/?uuid=aef92f97-85f5-4ed6-a5c8-e85bb440a742” } , “mendeley” : { “formattedCitation” : “17”, “plainTextFormattedCitation” : “17”, “previouslyFormattedCitation” : “17” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }17. The required amount of TG was added to the Na2S solution while stirring. The Na2S-TG solution was then added dropwise to the CdCl2 while constantly stirring using a magnet. As particle growth started with the formation of precipitation, the colour of the solution changed from colourless to orange for 0.0 mL TG (S0), yellow for 0.1 mL TG (S1), lemon-yellow for 0.2 mL TG (S2), lemon for 0.3 mL TG (S3), and whitish-lemon for 0.8 mL TG (S5). The five CdS precipitates with varying particle sizes were washed with ethanol several times to remove impurities and unreacted reactants. The precipitate was then collected by centrifuge for 5 minutes at 5000 rpm and then dried in an air oven for 10 hrs at 50 ?. After 10 hrs in the oven, the quantity of the powder decreased drastically suggesting removal of impurities and large quantities of water. The S3 sample was annealed to observe the effects of temperature and crystallinity. Annealing was carried in an argon-rich atmosphere for 2 hrs at 200?, 350?, 500? and 700 ?.

3.4 Gas phase method
The process uses a gas, which is normally inert, at pressures high enough to stimulate particle formation, but low enough to permit the fabrication of spherical particles ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “author” : { “dropping-particle” : “”, “family” : “L.”, “given” : “Wolfgang.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “AZoNano”, “id” : “ITEM-1”, “issued” : { “date-parts” : “2004” }, “page” : “1-6”, “title” : “Bottom u00ad up Methods for Making Nanotechnology Products What Processes are used for Bottom u00ad up”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=8c410469-bb84-439c-98bf-2659c1ba016e” } , “mendeley” : { “formattedCitation” : “18”, “plainTextFormattedCitation” : “18”, “previouslyFormattedCitation” : “18” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }18. Metal is introduced onto a heated element and is swiftly melted. The metal is quickly taken to temperatures far above the melting point, but less than the boiling point, so that a suitable vapour pressure is achieved. Gas is continuously introduced into the chamber and removed by the pumps, so the gas flow moves the evaporated metal away from the hot element. As the gas cools the metal vapour, nanometre-sized particles crystallize. The particles are liquid since they are still too hot to be solid. These liquid particles collide and coalesce in a controlled environment so that the particles grow to specification, remaining spherical and with smooth surfaces. As the liquid particles are further cooled under control, they become solid and grow no longer. At this point the nanoparticles are very reactive, so they are coated with a material that prevents agglomeration with other particles.

3.4.1 Pulsed laser deposition
3.4.1.1 Introduction
Pulsed laser deposition (PLD) is a physical vapour technique that utilizes a focused high power pulsed laser beam to evaporate a target ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “ISBN” : “9780471447092”, “author” : { “dropping-particle” : “”, “family” : “Eason, Robert (Optoelectronics Research Centre University of Southampton”, “given” : “UK)”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “2007” }, “page” : “707”, “title” : “Pulsed Laser Deposition of Thin Films: Applications-Led Growth of Functional Materials”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=258d7cf4-e827-4863-b060-cd5bd7d26456” } , “mendeley” : { “formattedCitation” : “19”, “plainTextFormattedCitation” : “19”, “previouslyFormattedCitation” : “19” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }19. A pulsed laser gets focused onto the desired target material inside a vacuum chamber in the presence of a background gas. A plasma plume is deposited on a substrate surface as a thin film. As a materials processing technique, laser ablation was utilized for the first time in the 1960’s, after the invention of a ruby laser ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “ISBN” : “0-471-59218-8”, “author” : { “dropping-particle” : “”, “family” : “Geohegan”, “given” : “David”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Hubler”, “given” : “Graham k.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Pulsed Laser Deposition of Thin Films”, “id” : “ITEM-1”, “issued” : { “date-parts” : “1994” }, “page” : “162-264”, “title” : “Pulsed Laser Deposition of Thin Films”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=f304939c-777d-4a7e-a99d-c3efdaba8f8c” } , “mendeley” : { “formattedCitation” : “20”, “plainTextFormattedCitation” : “20”, “previouslyFormattedCitation” : “20” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }20. The discovery of high-temperature superconductors in late 1986 reinvented the PLD technique. Lasers with higher repetition rate than the early ruby laser made the thin film growth possible, and since then PLD has evolved into a broadly applicable technique in the field of research leading to rapid development. This technique boasts of versatility and simplicity in implementation as advantages ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1002/9780470052129.ch16”, “ISBN” : “0000000000”, “abstract” : “Chapter 3 u2013 Pulsed laser deposition of oxides 29 CHAPTER 3 PULSED LASER DEPOSITION OF OXIDES 3.1 Introduction As a materials processing technique, laser ablation was utilized for the first time in the 1960’s, after the first commercial ruby laser was invented 1 . Nevertheless, as a thin film growth method it did not attract much research interest until the late 1980u00b4s 2 , when it has been used for growing high temperature superconductor films. Since then, the development of the pulsed laser deposition (PLD) technique has been more rapid and the amount of research devoted to this topic has increased dramatically. The advantages of PLD are the simplicity and versatility of the experiments. By using high-power pulsed UV-lasers and a vacuum chamber, a variety of stoichiometric oxide films can be grown in a reactive oxygen background gas without the need for further processing. This chapter is mainly based on Chrisey and Hubler’s book on ” Pulsed Laser Deposition of Thin Films ” 3 . 3.2 Chronological Development of PLD 1916 -Albert Einstein postulates the stimulated emission process 1960 -Theodore H. Maiman constructs the first optical maser using a rod of ruby as the lasing medium. 1962 -Breech and Cross use a ruby laser to vaporize and excite atoms from a solid surface. 1965 -Smith and Turner use a ruby laser to deposit thin films (this marked the very beginning of the development of the pulsed laser deposition technique). Early 1980’s -marked the creation of the first technological installation for laser deposition and epitaxy. A few research groups (mostly in the former USSR) achieved remarkable results on manufacturing thin-film structures using laser technology. 1987 -PLD was successfully used to grow high-temperature superconducting films.”, “author” : { “dropping-particle” : “”, “family” : “Popovici”, “given” : “N.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Pulsed Laser Deposition of Oxides”, “id” : “ITEM-1”, “issued” : { “date-parts” : “2009” }, “page” : “29-48”, “title” : “Pulsed Laser Deposition of Oxides”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=bfa245e9-e84b-4267-a12b-257890fea42b” } , “mendeley” : { “formattedCitation” : “21”, “plainTextFormattedCitation” : “21”, “previouslyFormattedCitation” : “21” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }21.
3.4.1.2 PLD Mechanism
A basic PLD technique setup (Fig.1), at first glance, it appears like a simple heating of the target material to get a plume deposit on a substrate, however, the mechanism is more complex. A pulsed laser is focused onto a dense and homogeneous target material to be deposited. For adequately high laser energy density, each laser pulse vaporizes a small amount of the material creating a plasma plume. The vaporized material is ejected from the target in a highly forward-directed plume. The ablation plume affords the material flux for film growth.

Fig. 1. Schematic diagram of a basic pulsed laser deposition (PLD) setup.

The whole process laser deposition happens in a vacuum chamber with the laser situated outside the chamber, meaning an extensive degree of freedom in the ablation geometry is possible. The vapour is a collection of atoms, molecules, ions and electrons, with the exact ratio and kinetic energy depending on the laser parameters (intensity, wavelength, pulse width) and to some degree on the target sample. A number of parameters play a role in the quality of the resultant thin film. Important parameters include the choice of substrate, the substrate temperature, and the absolute and relative kinetic energies and/or arrival constituents within the plume.
The PLD technique can generally be divided into four stages;
The laser interaction with the target material.

Formation of the plasma plume from ablation of materials.

Deposition of the plasma plume onto the substrate.

Nucleation and growth of a thin film on the substrate surface.

Each and every one of these steps is dependent on the material at play and experimental parameters such as laser wavelength, laser fluence and pulse width, background gas type and pressure, substrate type and temperature, and deposition geometry.

3.4.1.3 The laser interaction with the target material
A laser beam located outside the vacuum chamber gets focused through a quartz glass onto the surface of the target material at an angle of 45° as shown in Fig. 1. At times, however, reactive gases like O2, Ar, and N2are used to vary the stoichiometry of the deposit. The angle is chosen to avoid further interaction of the laser with an outgoing plume. Upon interaction of a photon with matter, the photon energy is coupled to the lattice through electronic processes. The absorption of the photon by material occurs in general over an optical depth of several nanometres upon which the energy in metals is transferred to the electronic system directly and in non-metallic systems typically to the lattice. An oscillation field occurs as a result of a collision cascade created between atoms in the material due to the absorbed energy. An atom (ion) can be removed from a target material if its total energy exceeds the binding energy ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1007/s13398-014-0173-7.2”, “ISBN” : “9780874216561”, “ISSN” : “0717-6163”, “PMID” : “15003161”, “abstract” : “Mycotoxins are small (MW approximately 700), toxic chemical products formed as secondary metabolites by a few fungal species that readily colonise crops and contaminate them with toxins in the field or after harvest. Ochratoxins and Aflatoxins are mycotoxins of major significance and hence there has been significant research on broad range of analytical and detection techniques that could be useful and practical. Due to the variety of structures of these toxins, it is impossible to use one standard technique for analysis and/or detection. Practical requirements for high-sensitivity analysis and the need for a specialist laboratory setting create challenges for routine analysis. Several existing analytical techniques, which offer flexible and broad-based methods of analysis and in some cases detection, have been discussed in this manuscript. There are a number of methods used, of which many are lab-based, but to our knowledge there seems to be no single technique that stands out above the rest, although analytical liquid chromatography, commonly linked with mass spectroscopy is likely to be popular. This review manuscript discusses (a) sample pre-treatment methods such as liquid-liquid extraction (LLE), supercritical fluid extraction (SFE), solid phase extraction (SPE), (b) separation methods such as (TLC), high performance liquid chromatography (HPLC), gas chromatography (GC), and capillary electrophoresis (CE) and (c) others such as ELISA. Further currents trends, advantages and disadvantages and future prospects of these methods have been discussed.”, “author” : { “dropping-particle” : “”, “family” : “Eason”, “given” : “Robert”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Wiley”, “id” : “ITEM-1”, “issue” : “1”, “issued” : { “date-parts” : “2007” }, “number-of-pages” : “1-5”, “title” : “Pulsed Laser Deposition of Thin Films”, “type” : “book” }, “uris” : “http://www.mendeley.com/documents/?uuid=1c5992a6-19e0-41ee-be28-985af32ade3e” } , “mendeley” : { “formattedCitation” : “22”, “plainTextFormattedCitation” : “22”, “previouslyFormattedCitation” : “22” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }22. Consequential electron excitations occur due to the oscillation of electrons leading to electron-lattice energy transfer. The absorbed energy per unit area by the target material depends on the fluence of the laser. The timescale for the electron energy transfer to the lattice in metals is of the order 1.5 ps and strongly dependent on the thermal conductivity, specific heat, and electron-phonon coupling ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1103/PhysRevB.50.8016”, “ISSN” : “0163-1829”, “author” : { “dropping-particle” : “”, “family” : “Wang”, “given” : “X. Y.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Riffe”, “given” : “D. M.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Lee”, “given” : “Y.-S.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Downer”, “given” : “M. C.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Physical Review B”, “id” : “ITEM-1”, “issue” : “11”, “issued” : { “date-parts” : “1994”, “9”, “15” }, “page” : “8016-8019”, “publisher” : “American Physical Society”, “title” : “Time-resolved electron-temperature measurement in a highly excited gold target using femtosecond thermionic emission”, “type” : “article-journal”, “volume” : “50” }, “uris” : “http://www.mendeley.com/documents/?uuid=643e7a2e-ffc3-39f7-ac13-614e07318008” } , “mendeley” : { “formattedCitation” : “23”, “plainTextFormattedCitation” : “23”, “previouslyFormattedCitation” : “23” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }23. For the non-metallic system, the relaxation time is between 10-12 and 10-3 s. The vaporization process can be described by the heat flow theory where the surface temperature of the target at the end of the laser pulse is determined by the light absorption and thermal diffusivity ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1109/ICTON.2011.5970839”, “ISBN” : “9781457708800”, “ISSN” : “21627339”, “abstract” : “One of the most versatile deposition techniques in solid-state physics and analytical chemistry is the vaporization of condensed matter using photons. A short-pulsed high-power laser beam is focused onto a sample surface thereby converting a finite volume of a solid instantaneously into its vapor phase constituents such as ions and neutrals. Subsequently, the vapor moves away from the target at a high velocity and can be sampled either to grow a film or being analyzed by various spectroscopic techniques. In this chapter, the focus is on general properties of pulsed laser ablation relevant for solid-state physics like the initial ablation processes, plume formation, and plume properties. Next, oxide thin film growth will be discussed and the growth of LaAlO 3 /SrTiO 3 heterostructures is presented as one example of tailoring oxide interfaces with surprising properties. The final discussion is on the topic of polymer ablation.”, “author” : { “dropping-particle” : “”, “family” : “Zawadzka”, “given” : “a”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Plociennik”, “given” : “P”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “u2026 (ICTON), 2011 13th u2026”, “id” : “ITEM-1”, “issued” : { “date-parts” : “2011” }, “page” : “89-112”, “title” : “Laser ablation and thin film deposition”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=cada1e01-729c-432c-a752-c081358a30c8” } , “mendeley” : { “formattedCitation” : “24”, “plainTextFormattedCitation” : “24”, “previouslyFormattedCitation” : “24” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }24.

3.4.1.4 Formation of the plasma plume from ablation of materials
In many PLD applications, an ability to predict and control the cluster composition of the ablation plume is critical. In particular, the presence of clusters or particulates in the ablation plume can have an adverse effect on the quality of homogeneous thin films grown in PLD ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “editor” : { “dropping-particle” : “”, “family” : “D.B. Chrisey”, “given” : “G.K. Hubler”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “1994” }, “publisher” : “Wiley-Interscience”, “publisher-place” : “New York”, “title” : “Pulsed Laser Deposition of Thin Films”, “type” : “book” }, “uris” : “http://www.mendeley.com/documents/?uuid=861fdf70-497e-496d-b929-d7d4633094f9” } , “mendeley” : { “formattedCitation” : “25”, “plainTextFormattedCitation” : “25”, “previouslyFormattedCitation” : “25” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }25. The material ablation mechanism and the total amount of emitted flux can change radically with a sufficient increase in fluence to induce explosive boiling of the target material. This process is termed as phase explosion,ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1007/s003390051357”, “ISBN” : “0947-8396”, “ISSN” : “09478396”, “abstract” : “Three kinds of thermal processes may lead to ma- terial loss from a laser-irradiated surface: 1) vaporization, 2) normal boiling, and 3) explosive boiling. The latter is equiva- lent to phase explosion. It is appropriate, at this point, to ex- clude u201csubsurface heatingu201d, as there are strong doubts about its existence. The relevance of the three processes depends on the laser pulse duration as well as on the temperature attained in the irradiated zone.We revisit the three thermal processes by noting that: 1) vaporization is not important for the short- est time-scales (<1ns). 2) Normal boiling is subject to ama- jor kinetic obstacle in the process of bubble diffusion, such motion being sufficiently slow that it will simply not occur for t <100 ns. This is because the value of the bubble diffu- sion coefficient leads to distances traveled which are atom- ically small for both 1ns and 100 ns, and for both T = Tm and T = 2Tm, with Tm being the melting temperature. 3) Phase explosion, notwithstanding the unfavorable time-scale (1u2013100 ns) advocated by Martynyuk, as carefully analyzed in this paper, is found to be the most efficient mechanism in the ablation process when looking at thermal processes. Here it should be recognized that a new field in the physics of condensed matter may be emerging when looking at phys- ical properties near the thermodynamic critical temperature, Ttc. In fact, laser irradiation experiments probably represent a unique tool to investigate matter under extreme thermody- namic conditions and on very short time-scales (ps or fs).”, “author” : { “dropping-particle” : “”, “family” : “Miotello”, “given” : “A.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Kelly”, “given” : “R.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Applied Physics A: Materials Science and Processing”, “id” : “ITEM-1”, “issue” : “7”, “issued” : { “date-parts” : “1999” }, “page” : “67-73”, “title” : “Laser-induced phase explosion: New physical problems when a condensed phase approaches the thermodynamic critical temperature”, “type” : “article-journal”, “volume” : “69” }, “uris” : “http://www.mendeley.com/documents/?uuid=2cfdeacb-cdb5-47f8-88a9-da01f2f4439a” } , “mendeley” : { “formattedCitation” : “26”, “plainTextFormattedCitation” : “26”, “previouslyFormattedCitation” : “26” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }26 it occurs at temperatures approaching the critical point, Tc. It is seen as an explosive relaxation of the laser-induced melt into a co-existent mixture of liquid droplets and vapour. Such hydrodynamic ejection of droplet-like particulates is one illustration of macroscopic sputtering ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1002/9780470052129.ch16”, “ISBN” : “0000000000”, “abstract” : “Chapter 3 u2013 Pulsed laser deposition of oxides 29 CHAPTER 3 PULSED LASER DEPOSITION OF OXIDES 3.1 Introduction As a materials processing technique, laser ablation was utilized for the first time in the 1960’s, after the first commercial ruby laser was invented 1 . Nevertheless, as a thin film growth method it did not attract much research interest until the late 1980u00b4s 2 , when it has been used for growing high temperature superconductor films. Since then, the development of the pulsed laser deposition (PLD) technique has been more rapid and the amount of research devoted to this topic has increased dramatically. The advantages of PLD are the simplicity and versatility of the experiments. By using high-power pulsed UV-lasers and a vacuum chamber, a variety of stoichiometric oxide films can be grown in a reactive oxygen background gas without the need for further processing. This chapter is mainly based on Chrisey and Hubler’s book on ” Pulsed Laser Deposition of Thin Films ” 3 . 3.2 Chronological Development of PLD 1916 -Albert Einstein postulates the stimulated emission process 1960 -Theodore H. Maiman constructs the first optical maser using a rod of ruby as the lasing medium. 1962 -Breech and Cross use a ruby laser to vaporize and excite atoms from a solid surface. 1965 -Smith and Turner use a ruby laser to deposit thin films (this marked the very beginning of the development of the pulsed laser deposition technique). Early 1980’s -marked the creation of the first technological installation for laser deposition and epitaxy. A few research groups (mostly in the former USSR) achieved remarkable results on manufacturing thin-film structures using laser technology. 1987 -PLD was successfully used to grow high-temperature superconducting films.”, “author” : { “dropping-particle” : “”, “family” : “Popovici”, “given” : “N.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Pulsed Laser Deposition of Oxides”, “id” : “ITEM-1”, “issued” : { “date-parts” : “2009” }, “page” : “29-48”, “title” : “Pulsed Laser Deposition of Oxides”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=bfa245e9-e84b-4267-a12b-257890fea42b” } , “mendeley” : { “formattedCitation” : “21”, “plainTextFormattedCitation” : “21”, “previouslyFormattedCitation” : “21” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }21. Another parameter that plays a role in a laser-induced plasma plume is the pulse length. In non-metallic systems, the absorption process occurs on a much shorter time scale compared to the thermal diffusion process, which gives rise to vaporization and plasma formation during the time scale of the pulse duration. There are two times scales for laser ablation; nanoseconds and femtoseconds, with different laser ablation mechanisms.
3.4.1.5 Deposition of the plasma plume onto the substrate.

Deposition of the ablated plume onto a substrate can be described by as follows: the particles from the plasma plume arrive at the substrate surface and are adsorbed, after which they may diffuse some distance before they react with each other and the surface and start to nucleate. The manner in which the particles start to nucleate may determine the structure or morphology of the growing film. The substrate temperature, Ts is a major factor in film deposition, along with supersaturation, S. The two parameters are related by
S=kBTslnR/Re (2.1)
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3.4.1.6 Nucleation and growth of a thin film on the substrate surface
The deposition of the evaporated plume on to the substrate can be described as a sequence; The evaporated particles in the plume arrive on the substrate surface and are adsorbed, after this they are expected diffuse a short distance before they react with each other and the surface and start to nucleate. The manner in which the particles nucleate will determine the structure or morphology of the growing film. Under certain circumstances, like high substrate temperature, diffusional interactions within the film and with the substrate, underneath the growing film surface, may consequently modify film composition and film properties ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1002/9780470052129.ch16”, “ISBN” : “0000000000”, “abstract” : “Chapter 3 u2013 Pulsed laser deposition of oxides 29 CHAPTER 3 PULSED LASER DEPOSITION OF OXIDES 3.1 Introduction As a materials processing technique, laser ablation was utilized for the first time in the 1960’s, after the first commercial ruby laser was invented 1 . Nevertheless, as a thin film growth method it did not attract much research interest until the late 1980u00b4s 2 , when it has been used for growing high temperature superconductor films. Since then, the development of the pulsed laser deposition (PLD) technique has been more rapid and the amount of research devoted to this topic has increased dramatically. The advantages of PLD are the simplicity and versatility of the experiments. By using high-power pulsed UV-lasers and a vacuum chamber, a variety of stoichiometric oxide films can be grown in a reactive oxygen background gas without the need for further processing. This chapter is mainly based on Chrisey and Hubler’s book on ” Pulsed Laser Deposition of Thin Films ” 3 . 3.2 Chronological Development of PLD 1916 -Albert Einstein postulates the stimulated emission process 1960 -Theodore H. Maiman constructs the first optical maser using a rod of ruby as the lasing medium. 1962 -Breech and Cross use a ruby laser to vaporize and excite atoms from a solid surface. 1965 -Smith and Turner use a ruby laser to deposit thin films (this marked the very beginning of the development of the pulsed laser deposition technique). Early 1980’s -marked the creation of the first technological installation for laser deposition and epitaxy. A few research groups (mostly in the former USSR) achieved remarkable results on manufacturing thin-film structures using laser technology. 1987 -PLD was successfully used to grow high-temperature superconducting films.”, “author” : { “dropping-particle” : “”, “family” : “Popovici”, “given” : “N.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Pulsed Laser Deposition of Oxides”, “id” : “ITEM-1”, “issued” : { “date-parts” : “2009” }, “page” : “29-48”, “title” : “Pulsed Laser Deposition of Oxides”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=bfa245e9-e84b-4267-a12b-257890fea42b” } , “mendeley” : { “formattedCitation” : “21”, “plainTextFormattedCitation” : “21”, “previouslyFormattedCitation” : “21” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }21. In general, the process of nucleation and growth is separated into three modes:
Volmer-Weber growth
Frank-van der Merwe growth
Stranski-Krastinov growth
Volmer-Weber nucleation mode
In this mode, the atoms are strongly bound together in the thin film more than they are to the substrate resulting in clusters. The intermolecular forces of attractions between the atoms attaching to the substrate surface are much stronger than the forces they will form with the substrate material. As soon as a nucleation site of the first layer forms, another layer follows on top of it resulting in the growth of islands
Frank-van der Merwe mode
This mode is also known as layer-by-layer growth, the interface energy is relatively low and layers form readily from nearly any size nuclei ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1007/978-0-387-73563-4”, “ISBN” : “9780387735627”, “ISSN” : “1098-6596”, “PMID” : “21”, “abstract” : “Systems at the surface of the Earth are continually responding to energy inputs derived from solar radiation or from the radiogenic heat in the interior. These energy inputs drive plate movements and erosion, exposing metastable …”, “author” : { “dropping-particle” : “”, “family” : “Brantley”, “given” : “Susan L.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “White”, “given” : “Art F.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Kubicki”, “given” : “James D.”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Kinetics of Water-Rock Interaction”, “id” : “ITEM-1”, “issue” : “June 2014”, “issued” : { “date-parts” : “2008” }, “number-of-pages” : “1-833”, “title” : “Kinetics of water-rock interaction”, “type” : “book” }, “uris” : “http://www.mendeley.com/documents/?uuid=3108722a-7ff9-4e6c-a126-a4f79bbc1a8f” } , “mendeley” : { “formattedCitation” : “29”, “plainTextFormattedCitation” : “29”, “previouslyFormattedCitation” : “29” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }29. The bonds to the substrate are stronger than the intermolecular forces of attractions between the atoms and molecules attaching to the substrate surface Nucleation sites are formed as before but as new material arrives it is incorporated into the first layer exclusively. Full monolayer growth involves the nucleation and growth of islands that are only one monolayer thick and grow to essentially complete coalescence before significant clusters are developed on the next film layer.ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “DOI” : “10.1166/jnn.2014.9120”, “ISBN” : “1533-4880”, “ISSN” : “15334880”, “abstract” : “This review summarizes the work principles of pulse laser deposition (PLD) apparatus, physical processes like ablation, and plasma plume formation accompanying the deposition of un-doped ZnO from target to substrate material. Various modes of deposition and factors influencing the properties\n of thin films such as substrate temperature, background gas pressure, laser energy density (laser fluence), target to substrate distance, repetition rate, oxygen partial pressure in deposition chamber, deposition time and post growth annealing which control deposition parameters such as adsorption,\n desorption, surface diffusion, nucleation, and crystallization/re-crystallization are also discussed in this review. Moreover, various film properties such as morphology, roughness of the film surface, film thickness, grain size, optical transmittance, sensitivity, electrical conductivity,\n uniformity and electrical resistivity of the deposited ZnO thin films have also been enumerated in the present review.”, “author” : { “dropping-particle” : “”, “family” : “Kumar”, “given” : “Rajesh”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Kumar”, “given” : “Girish”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “Umar”, “given” : “Ahmad”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Journal of Nanoscience and Nanotechnology”, “id” : “ITEM-1”, “issue” : “2”, “issued” : { “date-parts” : “2014” }, “page” : “1911-1930”, “title” : “Pulse Laser Deposited Nanostructured ZnO Thin Films: A Review”, “type” : “article-journal”, “volume” : “14” }, “uris” : “http://www.mendeley.com/documents/?uuid=3e5cf644-2bd0-488e-82f2-736c2c5430e0” } , “mendeley” : { “formattedCitation” : “30”, “plainTextFormattedCitation” : “30”, “previouslyFormattedCitation” : “30” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }30.

Stranski-Krastinov mode
Also known as the three-dimensional island growth mode follows a two-step process: primarily, complete films of adsorbates, up to several monolayers thick, grow in a layer-by-layer fashion on a crystal substrate. Beyond a critical layer thickness, which depends on strain and the chemical potential of the deposited film, growth continues through the nucleation and coalescence of adsorbate ‘islands ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “author” : { “dropping-particle” : “”, “family” : “Venables”, “given” : “John”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “2000” }, “publisher” : “Cambridge University Press”, “title” : “Introduction to surface and thin film processes”, “type” : “book” }, “uris” : “http://www.mendeley.com/documents/?uuid=3686f9fe-7c8a-4648-bf69-5eee26c222c9” } , “mendeley” : { “formattedCitation” : “31”, “plainTextFormattedCitation” : “31”, “previouslyFormattedCitation” : “31” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }31ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “author” : { “dropping-particle” : “”, “family” : “Pimpinelli, Alberto”, “given” : “and Jacques Villain”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “1998” }, “publisher” : “Cambridge university press”, “publisher-place” : “Cambridge”, “title” : “Physics of crystal growth”, “type” : “article-journal”, “volume” : “19” }, “uris” : “http://www.mendeley.com/documents/?uuid=2a9e612a-3603-4c82-ad30-e717859bc7d2” } , “mendeley” : { “formattedCitation” : “32”, “plainTextFormattedCitation” : “32”, “previouslyFormattedCitation” : “32” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }32ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “author” : { “dropping-particle” : “”, “family” : “Eaglesham, D. J.”, “given” : “and M. Cerullo”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “container-title” : “Physical review letters”, “id” : “ITEM-1”, “issue” : “16”, “issued” : { “date-parts” : “1990” }, “page” : “1943”, “title” : “Dislocation-free stranski-krastanow growth of Ge on Si (100)”, “type” : “article-journal”, “volume” : “64” }, “uris” : “http://www.mendeley.com/documents/?uuid=e19eb29f-107d-44e6-bc8b-56f62229a214” } , “mendeley” : { “formattedCitation” : “33”, “plainTextFormattedCitation” : “33”, “previouslyFormattedCitation” : “33” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }33.

Fig.2. Thin film growth modes (a) Stranski-Krastinov, (b) Volmer-Weber, and (c) Frank-van der Merwe mode.

The selection of the growth mode in a substrate-film system depends on (a) the thermodynamics that relates the surface energies of the film and substrate and (b) the film substrate interface energy.

3.4.2 Sputter coating
Sputter coating is a technique usually used to coat electron microscope samples with gold (Au). A conductive layer of gold is created to prevent charging, reduce thermal damage and improve imaging ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “abstract” : “Coating of samples is required in the field of electron microscopy to enable orimprove the imaging of samples.Creating a conductive layer of metal on the sample inhibits charging, reducesthermal damage and improves the secondary electron signal required fortopographic examination in the SEM.Fine carbon layers, being transparent to the electron beam but conductive, areneeded for x-ray microanalysis, to support films on grids and back up replicasto be imaged in the TEM. The coating technique used depends on theresolution and application.The Leica EM ACE coater family provides the perfect solution for everyapplication.”, “author” : { “dropping-particle” : “”, “family” : “Vladu00e1r”, “given” : “Andru00e1s E-“, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issue” : “April”, “issued” : { “date-parts” : “2015” }, “page” : “2”, “title” : “Strategies for scanning electron microscopy sample preparation and characterization of multiwall carbon nanotube polymer composites”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=538dc238-a943-461e-9710-671786c1ec19” } , “mendeley” : { “formattedCitation” : “34”, “plainTextFormattedCitation” : “34”, “previouslyFormattedCitation” : “34” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }34. Heavy argon gas atoms are used to bombard a gold target. Ejected gold atoms by ionized gas are deposited on CdS surface placed in the path of the resulting plume. A low vacuum environment is used (0.1 to 0.05 mbar), which with one of the modern low voltage sputter coaters, enables metal to be deposited at up to 1nm/s ADDIN CSL_CITATION { “citationItems” : { “id” : “ITEM-1”, “itemData” : { “author” : { “dropping-particle” : “”, “family” : “The”, “given” : “Operation”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” }, { “dropping-particle” : “”, “family” : “For”, “given” : “Sputter Coater”, “non-dropping-particle” : “”, “parse-names” : false, “suffix” : “” } , “id” : “ITEM-1”, “issued” : { “date-parts” : “0” }, “title” : “Plasma Sputter Coating”, “type” : “article-journal” }, “uris” : “http://www.mendeley.com/documents/?uuid=53f3384f-8bca-49c9-b791-dce5bb7fe572” } , “mendeley” : { “formattedCitation” : “35”, “plainTextFormattedCitation” : “35” }, “properties” : { “noteIndex” : 0 }, “schema” : “https://github.com/citation-style-language/schema/raw/master/csl-citation.json” }35.References
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