Presentation on theme: "NANOTECHNOLOGY INPUTS, PROCESSES, FORMS, AND PRODUCTS."— Presentation transcript:
1 NANOTECHNOLOGYINPUTS, PROCESSES, FORMS, AND PRODUCTS
2 TABLE OF CONTENTS SLIDE 1 – COVER SLIDE 2 – TABLE OF CONTENTS SLIDE 3 – INTRODUCTION TO REPORTSLIDE 4 – A NOTE REGARDING THE RESEARCH METHODSLIDE 5 – INTRODUCTION TO INPUTSSLIDE 6 – CARBON ATOM PROPERTIESSLIDE 7 – CARBON ATOM APPLICATIONSSLIDE 8 – GOLD ATOM PROPERTIESSLIDE 9 - GOLD ATOM APPLICATIONSSLIDE 10 - ALUMINUM ATOM PROPERTIESSLIDE 11 - ALUMINUM ATOM APPLICATIONSSLIDE 12 – TITANIUM ATOM PROPERTIESSLIDE 13 – TITANIUM ATOM APPLICATIONSSLIDE 14 – OXYGEN ATOM PROPERTIESSLIDE 15 – OXYGEN ATOM APPLICATIONSSLIDE 16 – SILVER ATOM PROPERTIESSLIDE 17 – SILVER ATOM APPLICATIONSSLIDE 18 – ZINC ATOM PROPERTIESSLIDE 19 – ZINC ATOM APPLICATIONSSLIDE 20 – MANGANESE ATOM PROPERTIESSLIDE 21 – MANGANESE ATOM APPLICATIONSSLIDE 22 – CALCIUM ATOM PROPERTIESSLIDE 23 – CALCIUM ATOM APPLICATIONSSLIDE 24 – HYDROGEN ATOM PROPERTIESSLIDES _ THROUGH _ - BIBLIOGRAPHY
3 INTRODUCTION TO REPORT This report on Nanotechnology: Inputs, Processes, Forms and Products, is intended to introduce the reader or audience member to the growing field of nanotechnology.This report will cover four topics within nanotechnology.Those are Inputs, Processes, Forms, and Products.The Inputs are atomic elements and the machines that manipulate them.The Processes are the acts of manipulation themselves.The Forms are the immediate output from these processes.The Products are the end-use services and devices that will demonstrate what is possible due to these advancements.The report will start with a survey of commonly used atomic elements, but will ultimately focus on the elements that have proven most useful to aerospace applications.Whereas much literature focuses on investing opportunities, or the pure science of nanotechnology, this report will restrict itself to aerospace applications.However, this report does not assume a general knowledge of nanotechnology on the part of the reader or audience member.A wide introduction to nanotechnology, with its many inputs, processes, forms, and products, will be necessary to understand what is possible.
4 A NOTE REGARDING THE RESEARCH METHOD The most common research tool for this report was the Internet, with Google being the starting point.As anyone who has done research on the Internet should well know, verification of information, and knowing for certain that what one is reading is correct, is a challenge.Knowing this, and having spent over half of my college education with Google as a tool, I've only used this search engine as a means to find sources that I doubt many people would have issues with.All sources are noted in the Bibliography.Web sources have the URL and date accessed.I humbly submit this report knowing full well that I am not scientist in this field, and have great respect those whose work I've cited.
5 INTRODUCTION TO INPUTS NetoholicInputs are the first topic that will be presented.Inputs include both atomic elements and the machines that researchers and industrialists use.Among the atomic elements that exist, I have focused among the most commonly used elements in this field.Those are carbon, gold, aluminum, titanium, oxygen, silver, zinc, manganese, calcium, and hydrogen.Typical machines used in nanotechnology are the atomic force microscope, the scanning tunneling microscope, chemical vapor deposition device, molecular beam epitaxy machine, lithography tools, diffraction tools, scanning electron microscope, the transmission electron microscope, and the near-field scanning optical microscope.Kristian Molhave
6 CARBON ATOM PROPERTIES Lee Kwok-san and Tong Shiu-singThe carbon atom is one of the most studied atoms in the world. It has a whole field of chemistry devoted to it – organic chemistry. Carbon exists in more compounds than any other element1.Carbon forms stable bonds with other atoms, including other carbon atoms, with its four outer-shell electrons2. These stable bonds are called covalent bonds.Often mined in coal, carbon usually exists in three different kinds of structures. These are called allotropes. The three allotropes are amorphous, graphite, and diamond3.A fourth, recently discovered allotrope, is known as the buckminsterfullerene, also known as C604. Its name comes from the allotrope's resemblance to the architecture of Buckminster. The C60 allotrope has 60 atoms arranged to form its shape.SaperaudOak Ridge National Laboratory
7 CARBON ATOM APPLICATIONS Timmymiller (both)Most research regarding carbon and nanotechnology has been the development and refinement of the carbon nanotube5. The nanotube is a variant on the bucky ball, and retains the same chemical bonding pattern.Among its abilities are superior tensile strength and electrical conduction. It can even substitute silicon for use in semiconductors6. There would seem to be no limit to what the nanotube can do at its scale.Nanotubes have been proposed as a means to store hydrogen. The weight ratio of carbon to hydrogen is twelve-to-one, which suggests a hydrogen storage capacity of 7.7% by weight7.Carbon atoms use only three of their outer orbital electrons to bond with other carbon atoms, to form the nanotube8. That leaves one free electron to bond with hydrogen.
8 GOLD ATOM PROPERTIESUSGSNo metal is more malleable or ductile than gold. It can also retain its shape and maintain its appearance longer than many other metals, which helps to explain in historical value9.Gold forms different bonds from that of carbon. It forms metallic bonds10. There are so many electrons that they are exchanged easily with other metal element atoms11. This phenomenon of electron exchange makes metals such as gold excellent conductors of electricity.Gold exists naturally in an unadulterated state12, and can be sorted from sands and gravel through a process known as panning. Its pure state is so soft that to add strength, gold is alloyed with other elements13.Gold can be plated onto particles, and can covert light into heat. This has proven useful as a cancer treatment in tests conducted at Rice University14. Gold's biological inertness contributed to its usefulness.Greg Robson
9 GOLD ATOM APPLICATIONS Georgia Tech (both)Gold nanoparticles have been shown to be effective for both detecting and treating cancer15. Researchers at Georgia Tech University determined that “absorption and scattering of electromagnetic radiation” is enhanced with the use of noble metals such as gold. This is possible because at the nanoscale, noble metals can increase their absorption of visible-to-ultraviolet light16.Gold nanoparticles can be bound to antibodies which then attach themselves to malignant cancer cells17. In this particular example, light near the infrared spectrum is used to locate the nanoparticles. Continuous exposure to a red laser can destroy the malignant cancer cells18.The benefits of laser therapy and gold nanoparticles for the treatment of cancer are localized damage to the cancer cells themselves (leaving other, desirable cells unharmed), the biological inertness and stability of gold, and gold’s absorptive properties19.
10 ALUMINUM ATOM PROPERTIES USGSAluminum is a common metal found on Earth. However, unlike gold, aluminum is rarely found unadulterated. Aluminum occurs most often naturally in a compound known as bauxite20.Aluminum does not form bonds like carbon. Even though aluminum has three outer shell electrons, it does not seek to acquire five more electrons necessary for a closed shell21. Most of its compounds only acquire three electrons.Aluminum does not rust like iron does, because the byproduct of oxidation, alumina, adheres readily to the aluminum surface22. However, the byproduct of oxidation of iron does not adhere to the iron surface.Aluminum’s low melting point (1220˚F, or 660˚C) makes it simple to recycle. Extracting aluminum from alumina requires more energy, by comparison23.
11 ALUMINUM ATOM APPLICATIONS The NEST Laboratory – University of DaytonResearchers at Argonne National Laboratory are interested in aluminum nanoparticles for propellants and hydrogen storage24. Current research emphasizes making stable, non-agglomerating aluminum nanoparticles. The increase in surface area as the size of the particles decrease means that greater amounts of hydrogen can be stored.For years, anodizing aluminum in sulphuric acid has resulted in a nanoporus coating, which prevents corrosion25. This material has been applied to the architectural and decorative markets.Stable cellular aluminum has been patented by Austria-based Metcomb26. Cellular aluminum has the primary advantage of being able to absorb impacts27. It has a regular structure that contains air bubbles, whose surface walls are coated with an oxide skin, which is a byproduct of the gas from the company's patented process.Cellular Solids Research Group - MIT
12 TITANIUM ATOM PROPERTIES Amethyst Galleries' Mineral GalleryTitanium is a common element found not only on Earth, but also on the Moon29. It is found in igneous (resulting from lava) rocks, iron ore, plants, and in humans. Pure titanium does not occur naturally.It burns in air, and is the only element that burns in nitrogen. It is also resistant to many kinds of acids and solutions, and like gold, is inert in humans30.Also like gold, titanium is part of the metallic group of elements. Titanium bonds with other metallic elements by sharing electrons freely. However, titanium does not conduct electricity as well as gold does31.Electrical conductivity results from the ability of electrons to move between two orbitals of a given atomic element, the valence orbital and the conductive orbital. The amount of energy required for electrons to move between these two orbitals must be very small32.
13 TITANIUM ATOM APPLICATIONS Lifecore BiomedicalTitanium nanotechnological applications have seen broad market and scientific uses.Titanium has been studied for use as orthopedic implants33. The titanium promotes bone-forming cell cohesion by mimicing the nanostructure surface topography of the original bone. The titanium was chemically modified to create the desired topography.Titanium dioxide (TiO2) has been used to separate proteins for analysis34. TiO2 creates hydroxyl radicals when exposed to UV light. Hydroxyl radicals are short-lived, so the use of the UV light controls the protein separation process.Titanium and TiO2 have been used in sun screen, wood protection, paint additives with protective or aesthetic qualities, and to break down nitrous oxides that cars and power plants emit35.Germes Online
14 OXYGEN ATOM PROPERTIES Oracle ThinkQuestOxygen is a gas at room temperature, and is essential for plant and animal life. The oxygen molecules that we breath are O2, whose oxygen atoms are bonded together with a double bond36. A double bond between two atoms is the sharing of two pairs of electrons37.Oxygen atoms exist in four allotropes: atomic oxygen, oxygen molecules (what we breath), ozone, and tetraoxygen38.Atomic oxygen does not exist on earth, but it does in space. It causes damage to spacecraft to oxygen's high reactivity.Ozone is O3. It exists in the atmosphere as a by-product of the sun's energy acting upon O2.Tetraoxygen (O4) is a recent discovery, and so far only exists as a laboratory product.Crosstek
15 OXYGEN ATOM APPLICATIONS Hewlett-Packard LaboratoriesOyxgen, due to its low boiling point temperature, is often paired with other elements when used in nanotechnology. Otherwise, loose oxygen atoms tend to form either O2 or O3.Oxygen has been used to convert hydrocarbons (molecules that contain hydrogen and carbon atoms) into organic compounds, which contain oxygen molecules39.Oyxgen may also be used for molecular switches40. The atom would act as a rotor, which would turn in response to electric charges41. The switch can be turned (written) to an on-position or an off-position, and also be detected (read)42.It is the writing and reading of switches at on/off positions that establishes the basis of electronic computing. With molecular switches, electronic computing can continue its quickly increasing speeds and storage capacities.
16 SILVER ATOM PROPERTIES Stirling Silver Jewelery 4 YouSilver and gold are similar. Both conduct heat and electricity very well43 and bond metallically. However, there are important differences.Silver does react biologically, though only when consumed in very large amounts44. Some individuals may experience contact allergies, while others after extensive exposure may develop permanent discoloration of the eyes and skin45. The EPA regulates the concentration of silver in drinking water46.Silver has many alloys, and has found extensive use in several industries. Alloys have been used in photographic film development, batteries, as well as dental fillings. When polished, silver is the best reflector of visible light, though it reflects UV light poorly47.SilverMedicine.org
17 SILVER ATOM APPLICATIONS JR Nanotech, PLCSilver is sold as having same or similar positive health affects at the nanoscale as it does at larger scales48. The element works as an antimicrobial agent49. Silver removes chemical compounds from the larger cell against which the silver is supposed to kill50.Silver's affects have been incorporated into clothing to kill bacteria and other deleterious microorganisms51. There exists a potential for coatings, that have silver nanoparticles, to be applied to surfaces that the public regularly touches, such as hospital furniture, hand rails, and mass transit vehicles52.Researchers at the Korean Research Institute of Bioscience and Biotechnology (KRIBB) have demonstrated a method to convert silver nanoparticles into gold nanoparticles53. The potential health treatment of gold nanoparticles have already been discussed.IoP Publishing
18 ZINC ATOM PROPERTIESZinc is a common element found on Earth, and is present in foods and water54. It is also sold as a supplement. There are relatively minor negative health affects due to overconsumption of zinc55.Zinc is the first element discussed so far that exhibits a property called superplasticity56. Superplasticity is the ability to stretch or deform without breaking. It is commonly added to alloys to enhance their ability to molded into desired shapes57.Zinc is a metal58. Therefore, it conducts electricity, but not as well as other metal elements59. However, it also reacts with oxygen and other non-metals, as well as acids60.Like silver, zinc is touted as having many positive health affects61. Whereas silver has specific antimicrobial uses, zinc consumption affects many areas on the human body, being linked to many improvements and preventative treatments62.Superb HerbsKobelco
19 ZINC ATOM APPLICATIONS Georgia Institute of TechnologyZinc oxide has been researched for its electrical conductive properties at the nanoscale63. Zinc oxide nanowires and nanobelts have been manipulated to create simple electrical components such as transistors, diodes and sensors64. The zinc oxide nanocomponents demonstrate semiconducting and piezoelectric properties65.When a material demonstrates piezoelectric phenomena by changing its dimensions66. An electric charge results in a mechanical change. The opposite is also true67. Mechanical change results in an electrical charge.Zinc nanocages have the ability to store hydrogen68. The zinc is arranged with oxygen to form a metal-organic framework69. Hydrogen storage efficiency can be as high as 10% of the weight of the nanocage70.T. Yildirim/NIST
20 MANGANESE ATOM PROPERTIES Yinon BentorManganese occurs naturally adulterated with other elements71, much like aluminun. Also like aluminum, it is often alloyed with other metals72. Whereas aluminum adds flexibility and ductility to metals, manganese adds toughness, hardness, and stiffness73.It is quite reactive, and will dissolve in water74. It is an added component to explosive material75. It also reacts biologically76.It is essential to human health77, and overconsumption from natural sources is difficult78. However, it is a regulated element when in use in laboratories. Its presence in drinking water is also regulated.When consumed in very high amounts in mining, industrial, or field-use environments, it can create a chronic neurological disorder known as manganism79.International Manganese Institute
21 MANGANESE ATOM APPLICATIONS Sinha, et al.Manganese can be used to clean air of volatile organic compounds (VOCs)80. Gold nanoparticles are sprayed onto a manganese oxide, and together they allow compounds to adhere to the surface81. The compounds then break down, cleaning the air.Manganese is part of chain of elements including calcium and oxygen that make up a cluster that breaks down water into its component parts – hydrogen and oxygen82. Researchers in Germany have found the geometric arrangement of manganese, calcium, and oxygen that promotes the breakdown of water. The goal is to enable hydrogen production with the manganese-calcium-oxygen cluster, water, and sunlight83.Manganese oxide has been used to build nanotubes84. The potential applications for this kind of nanotube include more efficient fuel cells and cathodes85.Nature
22 CALCIUM ATOM PROPERTIES Calcium is a metallic element86, like most of the elements discussed so far. Also like aluminum and manganese, is does not occur in nature by itself. It is often found in limestone and gypsum deposits. Despite being one of the most abundant metals, its highly reactive nature delayed its discovery as a single element87.Calcium is a well-known element, existing either naturally in many foods, or as an additive or supplement. It is the most common mineral in the human body, and is found predominantly in teeth and bones88. Overconsumption of calcium from diet and supplements is very uncommon89.When exposed to air, calcium attracts oxygen and nitrogen to form a protective coating90. Calcium exposed to water reacts to produce calcium hydroxide plus hydrogen91. At least one university (Ohio State in Columbus) is researching ways to refine the hydrogen production process using calcium compounds92.University of Washington
23 CALCIUM ATOM APPLICATIONS Fujihara, et al.Calcium carbonate nanoparticles have been shown to deliver drugs for the treatment of cancer93. Two different calcium compounds are stirred together with drug to create nanoparticles containing the calcium compound and drug94. The nanoparticle has been demonstrated to be stable for up to a week inside the body.Calcium carbonate composite nanofibers have been studied for use in guided bone reconstruction membranes95. Results have been positive for cell attachment to the membrane96. Calcium carbonate is also used as a bone-filling material itself97.Calcium phosphate nanoparticles have been shown to be effective gene carriers98. Until recently, DNA would degrade before it could have an affect upon the cancer cell99. The calcium and the phosphorous need to be carefully balanced in order for their nanoparticle to function correctly.Netzsch Feinmahltechnik
24 HYDROGEN ATOM PROPERTIES Hydrogen is the most common element in the universe, and has one of the simplest atomic structures. It consists of one electron in orbit around one proton100, making it the smallest atomic element. Hydrogen's light weight keeps it from remaining in the earth's atmosphere101.Hydrogen occurs mostly on earth in water102. Therefore, it occurs in all plants, animals and humans. It also occurs in hydrocarbons, which makes up fossil fuels.Hydrogen occurs not only in compounds, but in distinct forms and isotopes. All elements have isotopes, but hydrogen presents the opportunity to explain them the simplest way possible.All atoms have a fixed amount of protons, which are bound to neutrons, at the center of the atom103. While the number of protons does not change for a given element, the number of neutrons can change104. The isotopes of hydrogen are proving useful.Dr. Rita Maria SambrunaMSN Encarta
25 HYDROGEN ATOM APPLICATIONS Hydrogen's role in nanotechnology is mostly that of a byproduct, rather than an actual nanoparticle affecting change at the nanoscale. Much research focuses on extracting hydrogen from other compounds.Hydrogen can be extracted from ammonia, which is NH A metal iridium surface can have a finely textured surface to which ammonia particle adhere The surface permits the breakdown of ammonia, releasing nitrogen and hydrogen gases.Hydrogen can be stored in nanotubes, though a French research team has found that storing hydrogen on carbon nanohorns may be more effective107. The team found the nanohorns to be more stable than nanotubes, because hydrogen the bonding strength between the nanohorns is greater than that of the nanotubes108.The problem with all current technologies is that storage methods are too expensive and/or do not meet expected benchmarks.moleculartorch.comCNRS
26 HOW THE ATOMIC FORCE MICROSCOPE (AFM)WORKS Atomic force microscopy is a type of scanning probe technique109. Scanning probe microscopes are used to measure distances at the micro-scale and smaller110. These microscopes use a cantilever-mounted tip which scans across a material surface, and the distance at which the tip moves vertically as it scans is measured111.The resolution of the AFM extends down to 10 picometers112 (one trillionth of a meter). The resolution detail is controlled by the conditions in which the AFM is used, such as use in a vacuum chamber and ambient temperature (lower is better)113. There exists different methods of detecting cantilever deflection.One method is to use a laser to focus light onto a mirror which is placed on top of the cantilever114. The mirror reflects the light to a position sensitive detector (PSD)115. Phase-sensitive detection measures the output from the PSD116.Binnig, et al.Meyer, Gehard and Amer, Nabil M.
27 HOW THE AFM IS USEDThe AFM is used to study a wide range of properties for many materials. “The materials being investigating include thin and thick film coatings, ceramics, composites, glasses, synthetic and biological membranes, metals, polymers, and semiconductors. The AFM is being applied to studies of phenomena such as abrasion, adhesion, cleaning, corrosion, etching, friction, lubrication, plating, and polishing”117.AFMs operate in three modes: contact, non-contact, and tapping mode118. Contact mode has a DC feedback amplifier controlling the distance between the sample to be analyzed, and the cantilever119. The tip makes physical contact with surface in this mode. Non-contact mode images surfaces by detecting the forces that attract the tip120. Tapping mode has the cantilever oscillate, having the tip come into contact with the sample quickly and repeatedly121.Of the three methods, contact is the most common, followed by tapping and non-contact122.Austrian Academy of SciencesSwiss Federal Institute of Technology Zurich
28 HOW THE SCANNING TUNNELING MICROSCOPE (STM)WORKS The scanning tunnelling microscope is the ancestor of the AFM. STM “measures a weak electrical current flowing between tip and sample as they are held a very distance apart”123. The use of this kind of microscope is limited to materials that can conduct electricity124.Electrically conductive elements have a large cloud of electrons that surround the nucleous, relative to non-conductive elements. The STM has a tip like the AFM, only the STM's tip does not come into direct contact with the examined material. Instead, when brought close to the material, an electric current can flow between the material and the tip due to the interaction of electrons between the tip and the material125.An image of the material is produced by measuring the amount of vertical displacement needed to keep the current constant126.Binnig, et al.Binnig, et al.Gold, measured with an STM.
29 HOW THE STM IS USEDCrommie Group, Lawrence Berkeley National LaboratoryThe inventions of the Scanning Tunneling Microscope and the Atomic Force Microscope opened up a new way of observing and controlling matter at the atomic scale127. Both machines are used concurrently128. The STM allowed researchers to learn more about the function of semiconductors, and how different metals react, at the atomic scale, when they are juxtaposed129.The STM can also manipulate the placement of atoms. The tip of the STM moves atoms by having it be positioned over the atom to be moved, and having the electric current match the adsorptive strength of the overall sample material130. The atom can then be guided to a new position without the atom detaching fully from the surface material.While current positioning is done either manually or with computer assistance, the National Institute of Standards and Technology is working on an Automated Atomic Assembler131.
30 HOW CHEMICAL VAPOR DEPOSITION (CVD) WORKS Chemical Vapor Deposition (CVD) converts gaseous material into a solid and deposits it onto another solid132. A gas delivery system moves the gaseous material, known as the precursor, to the reactor chamber, where it is deposited upon the substrate133. An energy source is needed to provide heat for deposition to occur, and a vacuum and exhaust system to vent out the extraneous gaseous molecules134.CVD belongs to a class of a vapor deposition techniques, including molecular beam epitaxy (MBE), that deposits one material atomically upon another135. Like the previously discusses microscopy techniques, they can be used in conjunction. Some processes are hybrids of two different systems136.CVD is unique in its ability to “deposit any element or compound”, and do so with very high purity, density, uniformity, economically, and below the material's melting point137.Michigan Tech Yap LabDual-RF-plasma CVD SystemThermal Chemical Vapor Deposition CVD System
31 HOW CVD IS USEDBoyd, et al.CVD is used in the manufacture of artificial diamond138. The diamond “is comparable in purity and properties to...natural diamond. The hardness of diamond, coupled with the conformality of CVD films, can be exploited to make tool coatings and inserts with long cutting lives”139.A new method of CVD has been demonstrated to collect and distribute atoms along a specific path140. The method is plasmon-assisted CVD, which differs from convetional CVD by use of a low-powered laser beam141. “The technique makes use of the plasmon resonance in nanoscale metal structures to produce the local heating necessary to initiate deposition...”142.Thermal CVD has been used to grow carbon nanotubes143. The growing process requires depositing Iron, Nickel, Cobalt, or an alloy of the three metals onto a substrate144. The substrate is etched, placed into the thermal CVD apparatus, etched again, and heated to produce carbon nanotubes145.
32 HOW MOLECULAR BEAM EPITAXY (MBE) WORKS When “atoms are deposited on a substrate and continue the same crystal structure as the substrate”146, this is called epitaxial growth. “Molecular beam epitaxy (MBE) is a term used denote epitaxial growth of compound semiconductor films by a process involving the reaction of one or more thermal molecular beams with a crystalline surface under ultra-high vacuum conditions”147. Molecular beams are typically generated by thermally evaporating elements, although other sources are used148.MBE requires an ultra-high vacuum (UHV) environment149. MBE systems include a vacuum system, a pumping system, liquid N2 panels, effusion cells, a substrate manipulator and analysis tools150. “The pumping system usually consists of ion pumps”151, which attract gas molecules due to the lower pressure maintained within the pump152. Effusion cells are where the element is thermally evaporated153.Dr. Werner WegsheiderInstitute of Semiconductor and Solid State Physics Austria
33 HOW MBE IS USEDSarikaya, et al.MBE is used in conjunction with other tools. It has been used to create quantum dots154, which belong to the semiconducting group of materials155. MBE has also been used to grow Gallium Nitride (GaN) quantum discs and Aluminum Gallium Nitride (AlGaN) nanocolumns156, which may have applications for optoelectronic devices.Such devices include lasers and light-emitting diodes (LEDs). GaN nanodiscs and AlGaN nanocolumns create lattice structures free of “atomic-scale defects, called dislocations”157. These dislocations have limited the spectral range of lasers, ranging between near-UV and green158.MBE has also been used to grow Germanium (Ge) quantum dots159. These have been grown on silicon, and potential applications include not only optoelectronics, but also “resonant tunneling diodes, thermoelectric cooler, cellular automata, and quantum computer[s]”160.Gallium Indium Arsenide (GaInAs) Quantum DotsBertness, et al.Cross-Section and Top View of GaN nanocolumns (or nanowires)
34 HOW LITHOGRAPHY FOR NANOTECHNOLOGY WORKS Lithographic tools are used to mass produce microchips and other semiconductor devices160. Lithography works by layering a material sensitive to light (or whatever will do the etching) upon a substrate, and exposing the sensitive material to a controlled light, etc, pattern161. At the nanoscale, lithography has been used to pattern a “substrate for selective growth of nanostructures”162.One example of lithography used was in the production of arrays of silver and gold-palladium nanoparticles163. These particles were created with a scanning transmission electron microscope (STEM). The STEM focused a 2 nanometer-diameter electron beam to create the pattern164.Another example is transmission electron beam ablation lithography, which works by “controllably ablating [removing by melting] evaporated metal films, pre-patterned with electron beam lithography”165.MEMS and Nanotechnology Clearinghouse
35 HOW LITHOGRAPHY FOR NANOTECHNOLOGY IS USED EV Group Australia and Komag, Inc., have partnered up to use nanoimprint lithography (NIL) to create discrete track recording (DTR) patterned magnetic disks166. NIL works by pressing molds “into a thin thermoplastic polymer film on a substratethat is heated above its glass transitiontemperature”167. This method allows for greater production quantities.Hot embossing imprint lithography has been used to form mechanical topography on polymer cell substrates168. These substrates are on the surface of joint replacements, biosensors, and drug delivery devices. The topography of these substrates can influence how well the body's cells adhere to the implant which uses the substrate.Nanoparticle self-assembly has been demonstrated with chemical lithography169. “[P]article arrangement is controlled by differences in reactivity – a characteristic determined by exposing particles and surfaces to an assortment of chemical treatments”170.Chou, et al.
36 HOW SCANNING ELECTRON MICROSCOPES WORK Scanning electron microscopes (SEMs) generate images based on the deflection of beamed electrons off a given sample171. An electron gun, consisting of a cathode and an anode, generate the beam by attracting electrons from the cathode to the anode172. The beam is focused using an objective lens173.What makes SEMs useful is their superior magnifying capability. Optical microscopes use visible light, whose wavelength ranges from 400 to 700 nanometers174. The wavelength of an electron varies depending on its momentum, and can be quite smaller than that of visible light175.This means that electrons that deflect off the sample do so at a lower wavelength than that of visible light, thus permitting greater resolution than what an optical microscope can provide. The sample information that SEMs can provide include topographical, atomic number, thickness, and composition information176.Material Science and Engineering Department at Iowa State University
37 HOW SCANNING ELECTRON MICROSCOPES ARE USED Seung Hoon Nahm Manipulators can operate inside an SEM, allowing real-time imaging of an experiment in progress177. The actual device that performs the manipulation is called an end-effector, and can include “[s]harpened metal wires, referred to as probes”178, AFM tips (also known as cantilevered probes), and microelectromechanical systems (MEMS)-based grippers179. These manipulators can work with focused ion beam (FIB) systems to perform failure analyses of semiconductor devices180.An example of an end-effector in use was in an SEM, armed with a cantilever manipulator with a force sensor tip181. The equipment was used to test the tensile properties of carbon nanotubes182. The SEM introduced hydrocarbon contamination to attach the nanotube to the sensor tip, in a process known as nano-welding183.
38 INTRODUCTION TO FORMSUniverity of Southern CaliforniaC’Nano Rhône-AlpesForms are the second topic that will be presented.Nano-sized creations can come in four dimensional forms: the 0th dimension (nanoparticles), the 1st dimension (nanowire or nanotube), the 2nd dimension (nanofilm or nanosheet), and the 3rd dimension (nanomachine).While the nanotube is three-dimensional (having diameter and length), it is useful to differentiate its form from that of more complex three-dimensional organizations.From an architectural reference, thinking of these dimensional forms in terms of point, line, plane, and mass respectively may be helpful.The properties and applications of these forms are varied and many. What elements are used, and in what manner of configuration, influence the nature of these forms. I will introduce examples to illustrate only that differences do exist among forms.Nanofilm Surface AnalysisBrent Silby
39 THE PROPERTIES OF 0-DIMENSIONAL NANOFORMS The nanoparticle label can be said to be a valid description of a given particle when that particle's effects are dominated by the rules of quantum mechanics184. The science of quantum mechanics describes the behavior and function of light and particles at their most discrete. What this means is that for nanoparticles, the effects of atomic behavior dominate the surface of particle, rather than its interior185.These particles can be engineered to have specific properties, “often accomplished by coating or encapsulating them within a shell of a preferred material… For example, the shell can alter the charge, functionality, and reactivity of the surface, and can enhance the stability and dispersibility of the colloidal [consisting of two different phases -- solid, liquid, etc] core. Magnetic, optical, or catalytic functions may be readily imparted to the dispersed colloidal matter depending on the properties of the coating.”186.Matthew Meineke
40 APPLICATIONS OF 0-DIMENSIONAL NANOFORMS The market for applications using nanoparticles has been realized187. Industry size was expected to be worth $900 million by 2005, with an average annual growth rate of 12.8% for the period between 2000 andOne example of nanoparticle applications are molecular tags189. The applications of gold nanoparticles, for cancer detection and treatment, were discussed earlier. Also discussed were the applications of aluminum nanoparticles for hydrogen storage.Magnetite nanoparticles have been proposed for use in molecular/nanoelectromechanical systems (MEMS/NEMS)190. These particles can be magnetized, placed into traps surrounded by conductors, and subjected to an electrical field. They then rotate, permitting mechanical power at a larger scale.Georgia TechThe NEST Laboratory – University of Dayton
41 PROPERTIES OF 1-DIMENSIONAL NANOFORMS Nanotubes and nanowires are two kinds of one-dimensional nanoforms. The names are suggestive; nanotubes have a hollow interior, while nanowires do not. The nanotube has gotten considerable press for its properties.Tests have demonstrated the stiffness of carbon nanotubes to extend up to 673 Gigapascals (GPa) or 1010 psi191. They “combine high stiffness with resilience and the ability to buckle and collapse in a reversible manner: even largely distorted configurations (axially compressed or twisted) can be due to elastic deformations with virtually no atomic defects involved.”192Nanowires have demonstrated interesting electromagnetic properties. For example, giant magnetoresistance (GMR) has been “observed at room temperature on [Cobalt/Copper] multilayered nanowires.”193 GMR “is the phenomenon where [electrical] resistance in certain materials drops dramatically when a magnetic field is applied.”194Future HiL. Piraux, et al.
42 APPLICATIONS OF 1-DIMENSIONAL NANOFORMS As mentioned earlier, there appears to be no limit as to the number of applications that the nanotube can perform. Structural and electrical properties have already been mentioned. The carbon nanotube can also “produce streams of electrons very efficiently (field emission), which can be used to create light in displays in televisions or computers, or even in domestic lighting, and they can enhance the fluorescence of materials they are close to.”195Nanowires (or nanofibers) have been studied for low-temperature electrical discharge, for use in lithium-ion batteries (the kind used in laptops and cell phones).196 The high surface area-to-volume ratio helps to “mitigate the slow electrochemical kinetics problem”.197 The slow kinetics problem is the decrease in charge delivered from the battery at low temperatures198.Erkki Halkka - ESA
43 PROPERTIES OF 2-DIMENSIONAL NANOFORMS Two-dimensional nanoforms can come in nanofilms or nanoplates. Like the carbon nanotube, they can display remarkable properties.A nanofilm, a nanomembrane, has been developed that can hold up to 70,000 times its weight in water, can pass through a hole 30,000 times smaller than the membrane itself, and be as large as 16 square centimeters.199 Its properties came from the way it was manufactured. The membrane is a hybrid of organic polymers with inorganic components200 within an interpenetrating network201. An interpenetrating network is “any material containing two polymers, each in network form.”202Zinc Oxide nanoplates have been shown to have a relatively large “surface area for heat dissipation and large field enhancement factors”.203 A large field enhancement factor lowers the threshold for electron emission.Vendamme, et al.
44 APPLICATIONS OF 2-DIMENSIONAL NANOFORMS Nanofilm applications have already been capitalized204.FIX BIBLIOGRAPHYVendamme, et al.
45 BIBLIOGRAPHYWhitten, et al , General Chemistry. 7th EdIbid.3. Accessed on 17 May 2007.4. Accessed on 17 May 2007.5. Accessed on 18 May 2007.6. Accessed 18 May 2007.7. Accessed 19 May 2007.8. Accessed13 June 2007.Accessed on 13 June 2007.Accessed on 16 June 2007.Accessed on 16 June 2007.12. Whitten 909.13. Accessed on 13 June 2007.14. Accessed on 13 June 2007.
46 J. Am. Chem. Soc.; (Article); 2006; 128(6); 2115-2120. BIBLIOGRAPHY15. “Cancer Cell Imaging and Photothermal Therapy in the Near-Infrared Region byUsing Gold Nanorods”. Huang, X.; El-Sayed, I. H.; Qian, W.; El-Sayed, M. A.J. Am. Chem. Soc.; (Article); 2006; 128(6);16. “Some Interesting Properties of Metals Confined in Time and Nanometer Spaceof Different Shapes”. Mostafa A. El-Sayed. Acc. Chem. Res. ; 2001; 34(4) pp17. “Cancer Cell Imaging and Photothermal Therapy in the Near-Infrared Region by18. Ibid.19.?cookieSet=1#abstract Accessed 14 June 2007.20. Accessed 14 June 2007.21. Accessed 16 June 2007.22. Accessed 16 June 2007.23. Ibid.
47 BIBLIOGRAPHY24. Accessed 16 June 2007.25. Accessed 16 June 2007.26. Accessed 17 June 2007.27. Accessed 17 June 2007.28. Accessed 17 June 2007.29. Accessed 17 June 2007.30. Accessed 19 June 2007.31. Accessed 19 June 2007.32. Polloc, Daniel D Thermocouples: Theories and Properties
48 BIBLIOGRAPHY33. Paulo Tambasco de Oliveira1 and Antonio Nanci. “Nanotexturing of titanium-based surfaces upregulates expression of bone sialoprotein and osteopontin by cultured osteogenic cells”. Biomaterials. Volume 25, Issue 3, February 2004, PagesAccessed 20 June 2007.35. Accessed 20 June 2007.36. Accessed 21 June 2007.37. Accessed 21 June 2007.38. Accessed 21 June 2007.39. Accessed 22 June 2007.40.Molecule_toggle_makes_nano_logic_ html Accessed 22 June 2007.
49 BIBLIOGRAPHY41. Ibid.42. Ibid.43. Accessed 22 June 2007.44. Accessed 22 June 2007.45. Ibid46. Ibid.47. Accessed 22 June 2007.48. Accessed 23 June 2007.49. Accessed 23 June 2007.50. Ibid.51. Accessed 23 June 2007.
51 BIBLIOGRAPHY63. Accessed 24 June 2007.64. Ibid.65. Ibid.66. Accessed 24 June 2007.67. Ibid.68. Accessed 24 June 2007.69. Ibid.70. Ibid.71. Accessed 24 June 2007.72. Ibid.73. Ibid.
52 BIBLIOGRAPHY74. Accessed 24 June 2007.75. Ibid.76. Ibid.June 2007.78. Accessed 24 June 2007.79. Accessed 24 June 2007.80. Accessed 24 June 2007.81. Ibid.82. Accessed 24 June 2007.83. Ibid.
53 BIBLIOGRAPHY84. Luis Hueso and Neil Mathur. “Nanotechnology: Dreams of a hollow future”. Nature. 427, (22 January 2004).85. Ibid.86. Accessed 25 June 2007.87. Accessed 25 June 2007.88. Accessed 25 June 2007.89. Ibid.90. Accessed 25 June 2007.91. Accessed 25 June 2007.
54 BIBLIOGRAPHY92.06070-Hydrogen_from_Coal_Projects.html Accessed 25 June 2007.93. Accessed 25 June 2007.94. Ibid.95. doi: /j.biomaterials Accessed 25 June 2007.96. Ibid.97. K. Fujihara, M. Kotaki and S. Ramakrishna. “Guided bone regenerationnext term membrane made of polycaprolactone/calcium carbonate composite nano-fibers”. Biomaterials. Volume 26, Issue 19, July 2005, Pages98. Accessed 25 June 2007.99. Ibid.
55 BIBLIOGRAPHYAccessed 26June 2006.Accessed 26 June 2006.102. Ibid.Accessed 26 June 2006.104. Ibid.Accessed26 June 2007.106. Ibid.Accessed 26 June 2007.108. Ibid.Accessed 28 June 2007.
56 BIBLIOGRAPHY110. Ibid.111. Ibid.Accessed28 June 2007Binnig, et al. “Atomic Force Microscope” Physical Review of Letters. Vol56. Issue 9. March 3, 1986.Meyer, Gehard and Amer, Nabil M. “Novel Optical Approach to AtomicForce Microscopy”. Applied Physics Letters. Vol 53. Issue 12. September 19,1988115. Ibid.116. Ibid.Accessed 28June 2007.
57 BIBLIOGRAPHYAccessed29 June 2007.119. Ibid.Accessed 2 July 2007.Accessed 2 July 2007.122. Ibid.Accessed 2 July 2007.124. Ibid.Accessed 2 July 2007., Binnig, G., and H. Rohrer. “Scanning Tunneling Microscopy” IBM Journal of Research and Development. Vol 30. NoAccessed 2 July 2007.
58 BIBLIOGRAPHY128. Ibid.129. Ibid.130.Accessed 3 July 2007.131.Accessed 3 July 2007Accessed 3 July 2007.Accessed3 July 2007.134. Ibid.Pierson, Hugh O., Handbook of Chemical Vapor Deposition: Principles, Technology and Applications. Noyes Publications: Park Ridge, New JerseyPierson.
59 BIBLIOGRAPHYAccessed 3 July 2007.Celii & Butler. “Diamond Chemical Vapor Deposition”. Annual Review of Physical Chemistry. Vol139. Ibid.Accessed 4 July 2007.141. Ibid.Accessed 4 July 2007.Accessed 4 July 2007.144. Ibid.145. Ibid.Accessed 8 July 2007.
60 BIBLIOGRAPHYCho, A. Y. and Arthur, J. R. “Molecular Beam Epitaxy”. Progress in Solid-State Chemistry. Vol 10. PartAccessed 8 July 2007.149.tesihtml/node24.html Accessed 8 July 2007.150. Ibid151. Ibid.152.ion-catalog.pdf Accessed 8 July 2007.153.epitaxie_files/whatismbe.html Accessed 8 July 2007.Accessed 29 July 2007.
61 BIBLIOGRAPHYAccessed 29 July 2007.J. Ristic, et al. “Characterization of GaN quantum discs embedded in AlxGa1-xN nanocolumns grown by molecular beam epitaxy”. Physical Review B. Vol 68. Issue 12. September 2003.Accessed 30 July 2007.158. Ibid.Accessed 30 July 2007.Accessed 30 July 2007.Accessed 31 July 2007.
62 BIBLIOGRAPHYAccessed 2 August 2007.Craighead, H.G., and Mankiewich, P.M. “Ultra-Small Metal Particle Arrays Produced by High Resolution Electron-Beam Lithography”. Journal of Applied Physics. Vol Issue 11. November 1982.164. Ibid.Michael D. Fischbein and Marija Drndić. “Sub-10 nm Device Fabrication in a Transmission Electron Microscope”. Nano Letters. Vol. 7. IssueAccessed 7 July 2007.Chou, et al. “Imprint of Sub-25 nm Vias and Trenches in Polymers”. Applied Physics Letters. Vol 67. Issue November 1995.168. Charest, et al. “Combined Microscale Mechanical Topography and Chemical Patterns on Polymer Cell Culture Substrates”. Biomaterials. Vol Issue. 11 April Pg
63 BIBLIOGRAPHYAccessed 12 August 2007.Ibid.Accessed 21 August 2007.Accessed 21 August 2007.241 Bohren and Clothiaux. Fundamentals of Atmospheric Radiation. Wiley-VHC, 2006.Accessed 21 August.Accessed 21 August 2007.Gupta, Rishi, and Stallcup II, Richard E. “Introduction to In Situ Nanomanipulation for Nanomaterials Engineering”. Scanning Microscopy for Nanotechnology. Ed by Zhou, Weilie, and Wang, Zhong Lin. Springer
64 BIBLIOGRAPHYGupta.179. Ibid.Gupta.Accessed 2 September 2007.182. Ibid.183. Ibid.Accessed 4 September 2007.Ibid.11 Caruso, Frank. “Nanoengineering of Particle Surfaces”. Advanced Materials. Vol 13. Issue 1. January 5, 2001.Accessed 7 September 2007.
65 BIBLIOGRAPHY188. Ibid.189. Mazzola, Laura. “Commercializing Nanotechnology”. Nature Biotechnology. Vol 21. Issue Accessed on-line on 6 September 2007.190. Zahn, Markus. “Magnetic Fluid and Nanoparticle Applications to Nanotechnology”. Journal of Nanoparticle Research. Vol 3. PgAccessed 7 September 2007.192. Qingzhong, Zhao, et al. “Ultimate Strength of Carbon Nanotubes: A Theoretical Study”. Physical Review B. Vol 65. Issue 14. Article March 27, 2002.193. Piraux, L., et al. “Giant Magnetoresistance in Magnetic Multilayered Nanowires”. Applied Physics Letters. Vol 65. Issue 19. Pg November 7, 1994.Accessed 10 September 2007.Holister, et al. Nanotubes. White paper. CMP Científica. January 2003.197. Sides, Charles R. and Martin, Charles R. “Nanostructured Electrodes and the Low-Temperature Performance of Li-Ion Batteries”. Advanced Materials. Vol Issue 1. January 6, 2005.
66 BIBLIOGRAPHYSides.199. Ibid.200. Vendamme, et al. “Robust free-standing nanomembranes of organic/inorganic interpenetrating networks”. Nature Materials. Vol 5. Pages June 1, 2006.201. Sharp, Kenneth G. “Inorganic/Organic Hybrid Materials”. Advanced Materials. Vol 10. Issue 15. Pg January 26, 1999.202. Vendamme, et al.Accessed 11 September 2007.Accessed 12 September 2007.