Copyright 2008, Stephen J. Fonash
Actin
A contractile protein found in muscle cells. Together with myosin, actin provides the mechanism for muscle contraction.
Adsorbate
A substance that becomes adsorbed at the interface or into the interfacial layer of another material, or adsorbent.
Albumin
The main protein in human blood and the key to the regulation of the osmotic pressure of blood. Chemically, albumin is soluble in water, precipitated by acid, and coagulated by heat.
Allowed energies
When electrons are trapped in structures such as in an atom or in a quantum
dot, they are allowed by nature to have only certain energies. These are
called allowed energies. The F=ma physics approach does not predict this fact
of nature but the quantum mechanics approach does.
Anisotropic
Not isotropic. Physics. Having properties that differ according to the direction of measurement.
Anneal
To subject (glass or metal) to a process of heating and slow cooling in order to toughen and reduce brittleness.
Antibodies
Specialized proteins produced by the cells of the immune system that counteract a specific foreign substance. The production of antibodies is the first line of defense in the body’s immune response.
Antigens
(Also known as immunogens.) Substances that can stimulate an immune response. Antigens are usually proteins or polysaccharides and include the coats, capsules, cell walls, flagella, fimbrae, and toxins of parasites, bacteria, viruses, and other microorganisms.
Assembly
A set of pieces that work together in unison as a mechanism or device.
Atomic
force microscope
A scientific instrument
which uses the deflection of a nanoscale tip at the end of a cantilever to
image a surface. The deflection at each given point on a surface of an object
is processed by a computer to create an image of the surface which then can
be observed by the human eye. Because the tip is so small and the deflection
detection used is so precise, the atomic force microscope (AFM) only responds
to a nano-sized region of the surface giving a very detailed computer-generated
picture of the surface.
Atoms
The basic building
blocks of matter. A chemical compound (i.e., a molecule) is made of atoms
arranged in a fixed relationship and according to a fixed recipe. Every solid,
liquid, and gas is made of atoms. There are about 92 different types of naturally
occurring, stable atoms. These different types are referred to as the elements.
There are some man-made atoms but these are made in accelerators and are not
stable. They only exist for a fraction of a second. Atoms are electrically
neutral; i.e., they have no net electrical charge.
ATP
Adenosine triphosphate, a high energy phosphate compound found in the body; one of the major forms of energy available for immediate use in the body.
Auger Electron
Electrons emitted during radiationless inner shell ionization of an atom.
Bacteria
A bacterium is a microorganism life form made up of one cell with no cell
nucleus. The plural is bacteria.
Backscattered Electrons
Produced by an incident electron colliding with the nucleus of an atom in the specimen. The incident electron is then scattered backward about 180 degrees with no appreciable loss of energy, an elastic collision.
Bands of Allowed Energies
When atoms are brought together to form a material, the available energy levels adjust to accommodate the neighboring atoms. The energy levels tend to adjust into separated groups of energy levels called "energy bands." This is not inherently a spacial separation; rather it is a difference in the energy values which are available to the electrons.
Basic Materials
Essential, fundamental substances used as inputs to production or manufacturing.
Biological Assembly
A group of living things that fit together to form a self-contained unit.
Bleach
To make white or colorless by means of chemicals or the sun's rays.
Bottom-Up nanofabricaton
In nanotechnology, the construction of machines by arranging atoms and molecules into more complex assemblies.
Brownian Motion
Motion of a particle in a fluid owing to thermal agitation,
Buckeyball
Short for buckminsterfullerene - molecules made up of 60 carbon atoms arranged in a series of interlocking hexagonal shapes, similar to a soccer ball.
Building Blocks
Units of construction or composition.
Carbon Nanotube
A cylinder-shaped structure resembling a rolled-up sheet of graphite that can be a conductor or semiconductor depending on the alignment of its carbon atoms.
Catalyst
A substance that increases the rate of a chemical reaction, without being consumed or produced by the reaction.
Cell
The basic unit of life of which all living matter is constituted.
Channel
The region under the gate through which current flows from the source to
the drain contacts, when the transistor is turned on.
Chemical Assembly
Process in which a disordered system of pre-existing components forms an organized structure or pattern as a consequence of specific, local interactions among the components themselves, without external direction.
Chemical
Bonding
When atoms are held together in a precise
relationship due to the interactions of their outer electrons.
Chemical Etching
Etching process where the removal of material is due to chemical reactions with the substrate.
Chemical Properties
A description of the way in which a substance reacts with another substance to change its composition.
Chemical Reaction
A process in which one substance is transformed into another.
Chemical Vapor Growth (Deposition)
This high temperature coating process, as it relates to tooling applications, involves the deposition of a solid material onto a heated substrate via a chemical reaction from a gas phase. This process can be done in atmosphere or vacuum.
Chip
A piece of semiconductor containing many electronic devices. A chip will usually
contain the transistors and circuits needed for some function such as a memory
chip. Today a chip can contain as many as a billion transistors.
Colloidal Chemistry
The subject of interface and colloid science.
Colloidal Solutions
A type of mechanical mixture where one substance is dispersed evenly throughout another. Because of this dispersal, some colloids have the appearance of solutions. A colloidal system consists of two separate phases: a dispersed phase (or internal phase) and a continuous phase (or dispersion medium). A colloidal system may be solid, liquid, or gaseous.
Complimentary DNA
Single-stranded DNA made in the laboratory from a messenger RNA template under the aegis of the enzyme reverse transcriptase. This form of DNA is often used as a probe in the physical mapping of a chromosome. Abbreviated as cDNA.
Composition
A mixture of ingredients.
Computer Data File
A file maintained in computer-readable form.
Contact
A region designed to allow electric current flow into or out of an electronic
device. Synonymous with terminal and electrode.
Dark Field
An illumination technique that makes the sample appear luminous against a background of little or no light.
Dendrimer
Artificial molecule structure that has tiny branches or sprigs sprouting from it, which allow it to carry drug molecules.
Deposition
Deposition is a process in which gas transforms into solid (also known as desublimation). The reverse of deposition is sublimation.
Diamond-like
bond
A carbon chemical bonding configuration
in which each carbon atom shares one electron with each of four adjacent carbon
atoms. This is the chemical bonding found for carbon in diamonds.
Dip Pen Lithography
(DPN) is a scanning probe lithography technique where an atomic force microscope tip is used to transfer molecules to a surface via a solvent meniscus.
DNA Strains
A section of DNA that differs in trivial ways from similar groups.
Drain
The heavily doped region in semiconductor
substrates located at the end of the channel in Field Effect Transistors;
carriers are flowing out of the transistor through the drain.
Drug
Molecules
Substances used in medicine to treat diseases or conditions.
Dry Chemical/Physical Etching
Also called Reacitve Ion Etching (RIE), A directed chemical etching process used in micro/nano fabrication in which chemically active ions are accelerated along electric field lines to meet a substrate perpendicular to its surface.
Dry Physical Etching
Also called Sputter Etching, bombardment of the target (substrate) by high energy ions (e.g. Ar+) extracted from plasma for the purpose of material removal from the target (etching); highly anisotropic, highly non-selective etching method.
E-beam Lithography
Using electron beams to create the mask patterns directly on a substrate. The wavelength of an electron beam is only a few picometers compared to the 248 to 365 nanometer wavelengths of light used to create the traditional photomasks.
Electrical Properties
Properties of a substance which determine its response to an electric field, such as its dielectric constant or conductivity.
Electrode
A region designed to allow electric current flow into or out of an electronic
device. Synonymous with terminal and contact.
Electomagnetic
spectrum
Energy composed of electric field and magnetic filed components which propagates
as a wave at the speed of light. Radio waves, visible light, microwaves, x-rays,
and infra-red are some of the wavelength (or equivalently energy) ranges in
the electromagnetic spectrum. The full spectrum is seen in the figure below
which gives wavelengths and the corresponding energy.
Electron
Negative particles that surround the nucleus of the atom. They have mass,
charge, and magnetic moment.
Electron microscope
A scientific instrument that employs a beam of electrons, generated just as
they are in a conventional (CRT) television tube, which passes through or
bounces back off of an object,. The amount of the beam that passes through
or bounces back is used to image and magnify the objects by manipulating the
electrons using electric and magnetic fields. The microscope that uses electrons
passing through the object for imaging is termed a transmission electron microscope.
(TEM). The microscope that uses electrons bouncing back from the object for
imaging is termed a scanning electron microscope (SEM). In both the TEM and
the SEM, the electron beam intensities coming through or bouncing back from
the object are processed by a computer to create an image that then can be
observed by the human eye.
Element
A type of atom. There are only 92 naturally
occurring types of atoms; i.e., there are only 92 elements.
Embossing Lithography
A technique for the fabrication of nanostructures on large surfaces. The method is based on the excellent replication fidelity obtained with polymers and combines thermo-plastic molding with common pattern transfer methods.
Emitted
Light
Light coming from an atom, quantum dot, or any material.
Environment
The local physical and chemical situation around a body. (A slightly different
meaning than the everyday usage referring to the air, water, etc quality experienced
by an individual.)
Etch Rate
The speed at which etching occurs. Typically measured in Angstroms per second.
Etching
The removal of selected portions of a layer of material from a substrate using a chemical or electrolytic process.
Excited state
Occurs when some of the electrons trapped in a system such as an atom or quantum
dot have acquired enough energy to move up in energy to normally empty higher
allowed energies.
External Pattern Control
Creation of a pattern through the use of various types of materials, light, heat, and a predesigned pattern.
Externally Imposed Patern
A pattern applied to a substrate through the use of external pattern control techniques such as photolithography.
Fabrication
The act of constructing something (as a piece of machinery).
Field Effect
Transistor (FET)
In these devices, the control contact is called the gate. The gate, which
literally gates (allows or disallows) current, uses the voltage applied to
it to create a channel underneath it. The other two contacts into which and
out of which current easily flows are termed the source
and drain. Current from the source to the drain is enabled
when the gate is turned on to create the channel. These devices are often
referred to as FETs.
Field
Emission Electron Microscope
A form of TEM or SEM which employs a beam of electrons produced by quantum
mechanical tunneling. In microscopy, this tunneling process has been traditionally
called field emission (FE). The TEM version is referred to as a FETEM. The
SEM version is referred to as a FESEM. Such instruments are capable of “seeing”
very small objects (including atoms in the case of the FETEM). In both the
FETEM and the FESEM, the electron beam intensities coming through or bouncing
back from the object are processed by a computer to create an image that then
can be observed by the human eye.
Field Emission Scanning Electron Microscope
A field emission microscope where the electron beam scans the sample and the electron information used to create the image originates from either the origional electron beam which has been deflected off the sample surface into a detector (backscatter emission), or from the sample's surface electrons which have been ejected due to the impact of the electron beam (secondary emission).
Field Emission Transmission Electron Microscope
A field emission microscope where the electron beam scans the sample and the electron information used to create the image originate from the origional electron beam which has been modified after passing through the sample.
Flagellar Micromotor
A microscale motor made of Flagellum; fine hair like structures on cell walls used for locomotion.
Flash Lithography
An imprint lithography method utilizing a low viscosity, photo-curable liquid, and a transparent, rigid template.
Fluoresce
Produce light when exposed to radiation of a particular wavelength.
Fluorescence
Light emitted when electrons in excited
state energies in an atom, molecule, quantum dot, or material give up
energy by falling back to their ground
state.
Fluorophores
Molecular label conjugated to an antibody that emits fluorescent light within a measurable color spectrum in response to a specific wavelength of laser light or chemical interaction.
Forbidden Energies
Electrons trapped in a very small structure such as in an atom or in a quantum
dot, they are allowed by nature to have only certain energies. The energies
that are not permitted constitute the forbidden energies.
Friction
The resistance encountered when one body is moved in contact with another.
Fuel Cells
A device that converts the energy of a fuel directly to electricity and heat, without combustion.
Functionalized
Chemically changed with the addition of molecules which are attached by chemical
bonding. These molecules, in turn, can be used to bond to other substances.
Gate
An electrode in field effect transistors
(FETs) which has a bias applied to it to induce or turn off a current flowing
between the other two electrodes (i.e., between the source and drain). Almost
negligible current flows into or out of the gate electrode.
Graphite-Type
Bond
A carbon chemical bonding configuration
in which each carbon atom shares one electron with each of three adjacent
carbon atoms. A fourth electron spends half the time above and half the time
below each carbon atom. This is the chemical bonding found for carbon in graphite.
Ground State
Occurs when all the electrons trapped in a system such as an atom or quantum
dot occupy the lowest allowed energies.
Hybrid
Anything that is a mixture of two different things.
Hybrid Nanofabrication
Nanofabrication utilizing both top-down and bottom-up nanofabrication tools and techinquies.
Hybrid Structures
Structures created by hybrid nanofabrication techniques.
Hydrophobic
Repelling, tending not to combine with, or incapable of dissolving in water.
Hydrophobicity
The Property of being hydrophobic.
Infra-red
That part of the electromagnetic spectrum
which has energies just below that of the visible part of the spectrum. Equivalently,
it has wavelengths just above that of the visible part of the spectrum.
Inherent Pattern
The pattern created naturally by a material.
Ion
An atom or molecule (compound) which has lost or gained one or more electrons.
It is, therefore, electrically charged.
Ion Beam Lithography
A variation of the electron beam lithography technique, using a focused ion beam (FIB) instead of an electron beam. In a similar setup to scanning electon microscopes, an ion beam scans across the substrate surface and exposes electron sensitive coating.
Ion Channels
A protein-coated pore in a cell membrane that selectively regulates the diffusion of ions into and out of the cell.
Ionized
The state in which an atom is missing one or more of its electrons, and is therefore positively charged.
Isotropic
In a subtractive process, the material is removed in all directions simultaneously, frequently at the same rate vertically and horizontally.
Kinesin
A family of microtubule motor proteins active in mitosis. The kinesins use chemical energy from the hydrolysis of ATP (adenosine triphosphatase) to generate mechanical force. They bind tightly to and move along the microtubules.
Layers
A single thickness, coat, fold, or stratum.
Linear Micromotors
A micro-scale linear motor. A linear motor is a multi-phase alternating current (AC) electric motor that has had its stator "unrolled" so that instead of producing a torque (rotation) it produces a linear force along its length.
Lithography
The process of copying a pattern onto a surface using light, electron beams, or X-rays.
Living Tissues
Any tissue of a living organism containing cells that are being replaced when they die.
Lymph Node
Gland that makes up part of the immune system that removes bacteria and foreign particles from the body.
Lymph System
The tissues and organs that produce, store, and carry white blood cells that fight infection and other diseases. This system includes the bone marrow, spleen, thymus and lymph glandsand a network of thin tubes that carry lymph and white blood cells into all the tissues of the body.
Macromolecule
A very large molecule, such as a polymer or protein, consisting of many smaller structural units linked together. Also called supermolecule.
Manufacturable
If something is manufacturable or possess manufacturability, it can be made
reliably and economically.
Mask
The pattern used in lithography that determines which areas are exposed and which are not.
Material Modification
The act of making changes in form or character to a material.
Mechanical Processes
The branch of physics concerned with the behaviour of physical bodies when subjected to forces or displacements, and the subsequent effect of the bodies on their environment.
Mechanical Properties
The properties of a material that reveal its elastic and inelastic (plastic) behavior when force is applied, thereby indicating its suitability for mechanical (load-bearing) application, fatigue limit, hardness, modulus of elasticity, tensile strength, and yield strength.
Meter
A basic unit of length used in the metric system. In terms of the English
set of length units, one meter is 39.4 inches or equivalently 3.28 feet in
length.
Microscopy
The examination of minute objects by means of a microscope, an instrument which provides an enlarged image of an object not visible with the naked eye.
Microtubules
A minute filament in living cells that is composed of the protein tubulin and occurs singly, in pairs, triplets or bundles. Microtubules help cells to maintain their shape; they also occur in cilia, flagella and the centrioles, and form the spindle during nuclear division.
Modification
Alteration: the act of making something different.
Mold
A frame or model around or on which something is formed or shaped.
Molecule Synthesis
The formation of molecules from simpler compounds or elements.
Molecules
The smallest division of a compound that still retains or exhibits all the properties of the substance.
Moltronics
Also called molecular electronics, an interdisciplinary theme that spans physics, chemistry, and materials science. The unifying feature of this area is the use of molecular building blocks for the fabrication of electronic components, both passive (e.g. resistive wires) and active (e.g. transistors).
Monolayer
A monolayer is a single, closely packed layer of atoms, molecules, or cells.
Nano-Electronics
Investigation, fabrication, characterization and application of functional electron devices with dimensions below 100 nm.
Nanofabrication
Fabrication, such as building or sculpting, at the nanoscale, on the level of individual molecules.
Nano-Imprinting
A method of fabricating nanometer scale patterns. It is a simple process with low cost, high throughput and high resolution. It creates patterns by mechanical deformation of imprint resist and subsequent processes. The imprint resist is typically a monomer or polymer formulation that is cured by heat or UV light during the imprinting. Adhesion between the resist and the template is controlled to allow proper release.
Nano-Indentation
Depth-sensing indentation testing in the submicrometer range and has been made possible by the development of 1) machines that can make such tiny indentations while recording load and displacement with very high accuracy and precision, and 2) analysis models by which the load displacement data can be interpreted to obtain hardness, modulus, and other mechanical properties.
Nanoparticle
Any microscopic particle less than about 100 nanometers (nm) in diameter.
Nanostructure
An arrangement, structure, or part of something of molecular dimensions.
Nanotube
A nanoscale tube-like structure, which can occur naturally in some minerals, or be man-made from a variety of materials including carbon.
Nanowire
A wire of a material (for example, a metal), the diameter of which is less than 100 nm.
Near-Infra-Red
That part of the infra-red range of the electromagnetic
spectrum which is closest in energy (or, equivalently wavelenght) to red.
Non-Destructive Testing
Generic term for all material tests, which detect material irregularities without damaging the work-piece.
Non-Invasive
Testing or measurement of some sample that is done without disturbing the
sample.
On-State
An operating condition of a transistor whereby the voltage and resistance between the source and drain are such that electron flow between them is possible.
Optical Lithography
A process used to selectively remove parts of a thin film (or the bulk of a substrate). It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical (photoresist, or simply "resist") on the substrate. A series of chemical treatments then engraves the exposure pattern into the material underneath the photoresist.
Optical
Microscope
A scientific instrument that employs light manipulated using lenses to magnify
objects. The image produced can be observed directly by the human eye without
computer processing.
Particle
A body having finite mass and internal structure but negligible dimensions.
Pathological
Pertaining to pathology, the path of medicine that treats the essential nature of disease.
Photo Lithography
Also called optical lithography, it is a process used to selectively remove parts of a thin film (or the bulk of a substrate). It uses light to transfer a geometric pattern from a photomask to a light-sensitive chemical (photoresist, or simply "resist") on the substrate. A series of chemical treatments then engraves the exposure pattern into the material underneath the photoresist.
Photon
The quantum of electromagnetic energy, regarded as a discrete particle having zero mass, no electric charge, and an indefinitely long lifetime.
Physical Application
To put on a surface through physical means.
Physical Assembly
To assemble through physical means.
Physical Contact
The act of touching physically, so that no air gaps exist between the materials.
Physical Fabrication
To fabricate through physical means.
Physical Properties
A description of the qualities of a substance that can be demonstrated without changing the composition of the substance.
Physical Vapor Deposition
Also termed “atomic deposition” is a process in which material vaporized from a source is transported in the form of a vapor through a vacuum to the substrate where it condenses.
Physiological
Of, or relating to physiology;the study of the mechanical, physical, and biochemical functions of living organisms.
Planar Structure
Structures having a two-dimensional characteristics.
Plasma
A low-density gas in which individual atoms are ionized.
Polymer
A high molecular weight organic compound, natural or synthetic, whose structure can be represented by a repeated small unit, the monomer (eg, polyethylene, rubber, cellulose).
Positive Ion
An atom having a net positive charge due to the loss of one of its negatively charged electrons.
Probe
An object or device used to investigate the unknown.
Protein
Complex organic molecules made up of amino acids. These molecules a key to
cell functioning.
Proton
One of the basic particles which makes up an atom. The proton is found in the nucleus and has a positive electrical charge equivalent to the negative charge of an electron and a mass similar to that of a neutron.
Quantum
dot
A nano-scale arrangement of atoms in a ball shape usually from about 2nm to
50nm in diameter. The atoms used are ones which form semiconductors or insulators
since these structures are used for their optical and electrical properties.
Quantum effects often dominate in these very small structures giving them
their name.
Quantum Mechanical
Of or pertaining to Quantum Mechanics.
Quantum
Mechanical Tunneling
A quantum mechanical phenomenon in which an electron crosses
a nano-scale region which should be impenetrable according to F=ma physics.
Quantum
Mechanics
Quantum mechanics uses probability to determine if something will happen instead
of the F=ma perspective of Newton. In the world of the nano-scale, quantum
mechanics usually works better than the F=ma picture.
Radicals
Two or more atoms bound together as a single unit and forming part of a molecule.
Raster
A scanning pattern of parallel lines.
Reflected
Light
Light that impinges on and then bounces back from a gas, liquid, or solid.
Resist
A coating material that is used to mask or protect select areas of a pattern during manufacturing.
Resolution
The ability to view adjacent objects as distinct structures.
Scanning
Systematic examination of a prescribed region.
Scanning Electron Microscopy
Using a microscope in which a finely focused beam of electrons is scanned across a specimen, and the electron intensity variations are used to construct an image of the specimen. This type of microscope is ideal for magnifications from 200 to 35,000.
Scanning Probe Tools
Types of microscopes that form images of surfaces using a physical probe that scans the specimen. An image of the surface is obtained by mechanically moving the probe in a raster scan of the specimen, line by line, and recording the probe-surface interaction as a function of position.
Scanning Tunneling
Microscope
A scientific instrument which uses quantum mechanical tunneling
at a nanoscale tip to image a surface. The electric current flowing by tunneling
at each point on a surface of an object is processed by a computer to create
an image of the surface which then can be observed by the human eye. The tip
is scanned across the whole surface to construct this image, Because the tip
is so small and the tunneling current is so dependent on what is directly
under the nano-scale tip, the scanning tunneling microscope (STM) only responds
to that nano-sized region of the surface directly under the tip giving a very
detailed computer-generated picture of the surface.
Secondary Electrons
Electrons generated as ionization products. They are called 'secondary' because they are generated by other radiation (the primary radiation). This radiation can be in the form of ions, electrons, or photons with sufficiently high energy, i.e. exceeding the ionization potential.
Selectivity
The difference in removal rate between two materials during an etching or CMP process.
Self-Assembly
Process in which a disordered system of pre-existing components forms an organized structure or pattern as a consequence of specific, local interactions among the components themselves, without external direction.
Semiconductor
A material which has a range of forbidden energy levels. This gap in the allowed
energies gives semiconductors an electric current carrying ability that is
between that of a metal and that of an insulator. The size of this energy
gap also gives semiconductors optical properties that range from opaque to
transparent to visible light.
Shape
The spatial arrangement of something as distinct from its substance.
Size
The physical dimensions, proportions, magnitude, or extent of an object.
Solution
A homogeneous mixture
of a solid, liquid, or gaseous substance (these are the solute) with a liquid
(the solvent).
Source
One of three terminals
in Field Effect Transistors; a heavily doped region from which majority carriers
are flowing into the channel.
Spin
Revolve quickly and repeatedly around one's own axis.
Sputtering
The ejection of atoms or groups of atoms from the surface of the cathode (negative electrode) of a vacuum tube as the result of heavy-ion impact; The use of this process to deposit a thin layer of metal on a glass, plastic, metal, or other surface in a vacuum.
Stamping
To imprint or impress with a mark, design, or seal.
Stamping (Soft) Lithography
A family of techniques for fabricating or replicating structures using elastomeric stamps, molds, and conformable photomasks. It is called "soft" because it uses elastomeric materials most notably PDMS. Soft lithography is generally used to construct features measured on the micrometer to nanometer scale.
Structure
The way in which parts are arranged or put together to form a whole.
Subtractive Processing Step
The removal of unwanted material from a substrate or film.
Substrate
The material of which something is made and from which it derives its special qualities.
Terminal
A region designed to allow electric current flow into or out of an electronic
device. Synonymous with contact and electrode.
Top Down Nanofabrication
Amanufacturing approach that uses the traditional workshop or microfabrication methods where externally-controlled tools are used to cut, mill and shape materials into the desired shape and order.
Topology
The manner in which the components of a subject are arranged or interrelated.
Transistor
A three terminal (i.e., three contacts
or equivalently three electrodes) electronic device.
One terminal (contact) is used to control the current flowing between two other
terminals (contacts). When a transistor is turned on, current flow between these
other two terminals is easy. When it is turned off, this flow is non existent.
Transmission Electron Microscope
A microscopy technique whereby a beam of electrons is transmitted through an ultra thin specimen, interacting with the specimen as it passes through it. An image is formed from the electrons transmitted through the specimen, magnified and focused by an objective lens and appears on an imaging screen, a fluorescent screen in most TEMs, plus a monitor, or on a layer of photographic film, or to be detected by a sensor such as a CCD camera.
Transmitted Light
Light that impinges on and then passes through a gas, liquid, or solid and
emerges on the other side.
Tunneling
Quantum mechanical concept whereby an electron is found on the opposite side of an insulating barrier without having passed through or around the barrier.
Ultra Violet
That part of the electromagnetic spectrum
which is closest in energy (or, equivalently wavelength) to Violet in the
visible spectrum.
Vapor Condensation
The change of the physical state of aggregation (or simply state) of matter from gaseous phase into liquid phase. When the transition happens from the gaseous phase into the solid phase directly, bypassing the liquid phase the change is called deposition, which is the opposite of sublimation.
Viruses
Organic macromolecules (large, high molecular weight molecules) that can invade
and take over the machinery of a cell.
Visible
light
That part of the electromagnetic spectrum
that can be picked up by the sensors of the human eye.
Wet Chemical Etching
Etching performed with a liquid etchant, as opposed to a plasma.
X-Ray Spectroscopy
A gathering name for several spectroscopic techniques for determining the electronic structure of materials by using x-ray excitation.
X-Rays
A relatively high-energy photon having a wavelength in the approximate range from 0.01 to 10 nanometers.