The Materials Characterization Lab (MCL) is a fully-staffed, user research facility at Penn State’s Materials Research Institute that offers researchers convenient and affordable access to a wide-range of state-of-the-art analytical instrumentation and services.
A focused electron beam (3-20 keV) is scanned across the sample surface. Atoms near the surface are ionized, and a fraction of the ionized atoms relax via the Auger process. The spectrometer ultimately measures the kinetic energy distribution of a portion of the Auger electrons that are emitted from the sample. The technique is inherently surface sensitive because the majority of the measured Auger electrons originate in the outer 5-10 nm of the sample surface.
An Atomic Force Microscope (AFM) provides 3 dimensional topographic information about a sample by probing its surface structure with a very sharp tip. The tip is scanned laterally across the surface, and the vertical movements of the tip are recorded and used to construct a quantitative 3 dimensional topographic map. The lateral resolution of the image can be as small as the tip radius (typically 5-15 nm), and the vertical resolution can be on the order of angstroms.
An Atomic Force Microscope (AFM) provides 3 dimensional topographic information about a sample by probing its surface structure with a very sharp tip. The tip is scanned laterally across the surface, and the vertical movements of the tip are recorded and used to construct a quantitative 3 dimensional topographic map. The lateral resolution of the image can be as small as the tip radius (typically 5-15 nm), and the vertical resolution can be on the order of angstroms.
Electrical characterization is preformed using a variety of temperature chambers, LCR meters, impedance analyzers, pA meters, DMMs, charge converters, lock-in amplifiers, dynamic signal analyzers, voltage amplifiers, and sample fixturing for bulks, films, and leaded samples. Many measurements are entirely automated with the GADD measurement program. GADD takes directions in the form of a short user generated script file (text file) and uses those directions to control the measurement hardware to collect data your way.
Scanning Electron Microscopy uses a focused electron beam to scan solid samples. Secondary electrons are emitted from the sample and collected to create an area map of the secondary emissions. Since the intensity of secondary emission is dependent on local morphology, the area map is a magnified image of the sample. Spatial resolution is as high as 1 nanometer for some instruments, but 4 nm is typical for most.
Scanning Electron Microscopy uses a focused electron beam to scan solid samples. Secondary electrons are emitted from the sample and collected to create an area map of the secondary emissions. Since the intensity of secondary emission is dependent on local morphology, the area map is a magnified image of the sample. Spatial resolution is as high as 1 nanometer for some instruments, but 4 nm is typical for most.
A finely focused (10 nm) Ga+ beam impinges on a sample surface with 30 kV kinetic energy. Ions in the sample are sputter removed leaving a crater. By controlling the location, beam size and current density of the ion beam, material can be selectively removed from sub-micron areas. The MCL FIB also contains in situ scanning electron microscopy (SEM) capabilities for real time imaging of the ion milling site and even 3D tomography. Options also include localized deposition of Pt via a gas injection system (GIS), selective removal of carbon-based materials and an in situ cryogenic stage.
<p>The focused ion beam (FIB) is an extension to a scanning electron microscope (SEM). With it one can image and modify a specimen with high spatial (~10 nm) resolution. Modifications include site specific material removal, material deposition and particle manipulation. In a FIB, a beam of ions impacts a sample and causes local sputtering, removing material in a controlled way. If a special deposition gas is introduced, it is decomposed on the surface and site-specific deposition occurs.
Infrared spectrometry is useful for the identification of both organic and inorganic compounds. Aggregates of atoms (or functional groups) such as C=O, -NO2, C-N, and C-F; just to name a few, are all associated with characteristic infrared absorptions. Thus, infrared spectrometry is ideal for the identification of functional groups present within a sample.
Infrared spectrometry is useful for the identification of both organic and inorganic compounds. Aggregates of atoms (or functional groups) such as C=O, -NO2, C-N, and C-F; just to name a few, are all associated with characteristic infrared absorptions. Thus, infrared spectrometry is ideal for the identification of functional groups present within a sample.
The nanoindenter is designed to measure the mechanical properties of surfaces on a submicroscopic scale. The indenter takes a small diamond, which is shaped as either a pyramid or a sphere, and pushes the diamond tip into the surface of the material being tested. The depth of indentation can range from a couple of hundred nanometers to a maximum of 4 microns. Typically, the radius across the indentation will be micron to 5 microns.
Optical profilometry is a rapid, nondestructive, and noncontact surface metrology technique. An optical profiler is a type of microscope in which light from a lamp is split into two paths by a beam splitter. One path directs the light onto the surface under test, the other path directs the light to a reference mirror. Reflections from the two surface are recombined and projected onto an array detector. When the path difference between the recombined beams is on the order of a few wavelengths of light or less interference can occur.
In the case of laser diffraction systems, the particle size reported is the diameter of a sphere that yields an equivalent light scattering pattern as the particle being measured. Laser diffraction works by measuring the angular variation in intensity of light scattered as a laser beam passes through a well dispersed sample. The angular scattering intensity received is then analyzed to calculate the size of the particles responsible for creating the scattering pattern.
This technique is usually used to measure particle size of materials in the submicron region down to below 1nm. Particles that are in suspension undergo Brownian motion caused by thermally induced collisions between solvent molecules and the material particles. When the particles are illuminated with a laser, the intensity of the scattered light fluctuates over time at a rate dependent upon the particle size; smaller particles are displaced further by the solvent molecules and move more rapidly.
Resolution of the WITec Confocal Raman instrument depends upon the wavelength of excitation laser and the Numerical Aperture (NA) of the objective. Currently, there are three wavelengths available for use with the instrument: (1) 488-nm; (2) 514-nm; and (3) 633-nm. MCL offers a number of top quality objectives to choose from, depending upon the requirements of the application. The three most commonly used objectives are the 40X (NA = 0.6), 100X (NA= 0.9), 100X immersion-oil (NA = 1.25) providing lateral resolutions (using 488-nm excitation) of, 488-nm, 325-nm, and 235-nm, respectively.
SAXS uses Cu Ka X-ray scattering at very small angles to probe structure in zones of electron density contrast with sizes in the range of 1nm to 100nm. Such structures can include particulate systems, multi-phase systems, pore structures, emulsions, biological and cellular structures and others. Information about size, shape, dispersity, periodicity, interphase boundary area and solution properites can be obtained. Specimens may be solids, films, powders, liguids, gels, crystalline or amorphous. Applications in polymers and biological samples are abundant and well known.
In a transmission electron microscope (TEM), a thin specimen (ideally 100 nm) is exposed to a high-energy (20 - 300 keV) electron beam. Images contain contrast due to diffraction, differences in atomic mass and/or thickness or crystalline structure. Crystallographic information can also be obtained from diffraction patterns. We can also collect elemental and chemical state maps via analysis of 1) emitted x-rays (Energy Dispersive Spectroscopy - EDS) or 2) the energy loss of electrons that have gone through the specimen (Electron Energy Loss Spectroscopy - EELS).
In a transmission electron microscope (TEM), a thin specimen (ideally 100 nm) is exposed to a high-energy (20 - 300 keV) electron beam. Images contain contrast due to diffraction, differences in atomic mass and/or thickness or crystalline structure. Crystallographic information can also be obtained from diffraction patterns. We can also collect elemental and chemical state maps via analysis of 1) emitted x-rays (Energy Dispersive Spectroscopy - EDS) or 2) the energy loss of electrons that have gone through the specimen (Electron Energy Loss Spectroscopy - EELS).
Surface Area is helpful to determine how materials react to other materials, or how they dissolve or burn. In order to determine surface area a sample contained in a tube is pretreated by evacuation, including heat, vacuum and some flowing gas to remove contaminants from the surface. The material is then cooled to cryogenic temperatures. An adsorptive is added to the material at controlled pressure increments. After each dose of adsorptive, the pressure is equilibrated and the quantity adsorbed is calculated.
Surface Area is helpful to determine how materials react to other materials, or how they dissolve or burn. In order to determine surface area a sample contained in a tube is pretreated by evacuation, including heat, vacuum and some flowing gas to remove contaminants from the surface. The material is then cooled to cryogenic temperatures. An adsorptive is added to the material at controlled pressure increments. After each dose of adsorptive, the pressure is equilibrated and the quantity adsorbed is calculated.
Surface Area is helpful to determine how materials react to other materials, or how they dissolve or burn. In order to determine surface area a sample contained in a tube is pretreated by evacuation, including heat, vacuum and some flowing gas to remove contaminants from the surface. The material is then cooled to cryogenic temperatures. An adsorptive is added to the material at controlled pressure increments. After each dose of adsorptive, the pressure is equilibrated and the quantity adsorbed is calculated.
In a transmission electron microscope (TEM), a thin specimen (ideally 100 nm) is exposed to a high-energy (20 - 300 keV) electron beam. Images contain contrast due to diffraction, differences in atomic mass and/or thickness or crystalline structure. Crystallographic information can also be obtained from diffraction patterns. We can also collect elemental and chemical state maps via analysis of 1) emitted x-rays (Energy Dispersive Spectroscopy ? EDS) or 2) the energy loss of electrons that have gone through the specimen (Electron Energy Loss Spectroscopy ? EELS).
In a transmission electron microscope (TEM), a thin specimen (ideally 100 nm) is exposed to a high-energy (20 - 300 keV) electron beam. Images contain contrast due to diffraction, differences in atomic mass and/or thickness or crystalline structure. Crystallographic information can also be obtained from diffraction patterns. We can also collect elemental and chemical state maps via analysis of 1) emitted x-rays (Energy Dispersive Spectroscopy - EDS) or 2) the energy loss of electrons that have gone through the specimen (Electron Energy Loss Spectroscopy - EELS).
Thermogravimetric Analysis measure changes in weight of a sample with increasing temperature. Measurements are used primarily to determine the composition of materials and to predict their thermal and oxidative stability. Also the technique is used to estimate the lifetime of a product, decomposition kinetics, moisture/volatile content, melting point, glass transition, heat capacity, crystallinity and purity.
The Perkin-Elmer Lambda 950 is a high performance UV/Vis/NIR spectrophotometer capable of making measurements in the 190-3300 nm range. The extreme versatility of this instrument permits the acquisition of spectra from almost any type of sample. The current suite of sampling accessories permits acquisition of transmission (variable angle), diffuse transmission, specular reflectance (variable angle: absolute and relative), diffuse reflectance, and total reflectance spectra.
This technique is based on the Photoelectric Effect. When a material is irradiated with x-rays, photoelectrons are subsequently ejected from the surface. The kinetic energy of an emitted photoelectron is equal to the difference between the photon energy, and the binding energy of the electron (K.E. = h? - B.E.). The technique is inherently surface sensitive because the majority of the measured photoelectrons originate in the outer 5-10 nm of the sample surface. The spectra contain information about the elemental composition, concentrations and chemical environments (i.e.
X-ray Diffraction is an analytical technique that utilizes an inherent property of the x-ray beam - the wavelength - and the laws of physics that determine how that beam interacts with matter to characterize materials. Classically, the technique has been applied primarily to well-ordered crystalline materials to determine crystal structures, identify phase composition, measure stress, preferred orientation and crystallinity, but the field also encompasses the characterization of non- or semi-crystalline materials via small angle x-ray scattering (SAXS).
X-ray Diffraction is an analytical technique that utilizes an inherent property of the x-ray beam - the wavelength - and the laws of physics that determine how that beam interacts with matter to characterize materials. Classically, the technique has been applied primarily to well-ordered crystalline materials to determine crystal structures, identify phase composition, measure stress, preferred orientation and crystallinity, but the field also encompasses the characterization of non- or semi-crystalline materials via small angle x-ray scattering (SAXS).
X-ray Diffraction is an analytical technique that utilizes an inherent property of the x-ray beam - the wavelength - and the laws of physics that determine how that beam interacts with matter to characterize materials. Classically, the technique has been applied primarily to well-ordered crystalline materials to determine crystal structures, identify phase composition, measure stress, preferred orientation and crystallinity, but the field also encompasses the characterization of non- or semi-crystalline materials via small angle x-ray scattering (SAXS).
X-ray Diffraction is an analytical technique that utilizes an inherent property of the x-ray beam - the wavelength - and the laws of physics that determine how that beam interacts with matter to characterize materials. Classically, the technique has been applied primarily to well-ordered crystalline materials to determine crystal structures, identify phase composition, measure stress, preferred orientation and crystallinity, but the field also encompasses the characterization of non- or semi-crystalline materials via small angle x-ray scattering (SAXS).
X-ray Diffraction is an analytical technique that utilizes an inherent property of the x-ray beam - the wavelength - and the laws of physics that determine how that beam interacts with matter to characterize materials. Classically, the technique has been applied primarily to well-ordered crystalline materials to determine crystal structures, identify phase composition, measure stress, preferred orientation and crystallinity, but the field also encompasses the characterization of non- or semi-crystalline materials via small angle x-ray scattering (SAXS).
MRFN.org is supported by the MRSEC Program of the National Science Foundation. Image in the header is courtesy of CRISP MRSEC.
