After Café Header Graphic

WHEN: Select Tuesdays 11:00 AM - 11:45 AM, 

WHERE: 3rd Floor Commons, Millennium Science Complex

WHO: Any student, staff, or faculty interested in learning more about MCL capabilities

A casual opportunity immediately following the Millennium Café to learn about the breadth of analytical capabilities within the Materials Characterization Laboratory (MCL).  These brief (30 minute) multi-technique and interdisciplinary talks will highlight applications (not theory) to provide useful insights to novice and experienced researchers working across various science and engineering challenges.

Watch Past After Café Talks on YouTube

After Café: Controlled Temperature and/or Atmosphere for Materials Characterization

Materials characterization is often performed under standard laboratory conditions.  However, this can lead to an incomplete view of the structure, chemistry, and overall properties of a material system under their eventual “real-world operating conditions”.  To address this gap researchers may employ strategies to collect their data under “in situ” conditions where temperature, pressure, and chemical composition of atmosphere are controlled. The insight gained via “in situ” characterization are critical to developing further understanding for advanced materials, catalysts, polymers, etc. and represent one of the DOE BES critical research aims. During this talk, I will discuss our capabilities at MCL to perform these in situ experiments with a specific focus on XRD, TEM, XPS and molecular spectroscopy applied to a broad range of materials.

Jordan Meyet
After Café: 3D Imaging of Materials Across Length Scales Using Complementary Techniques

A multimodal/multiscale approach to the characterization of materials or devices can provide important information about defects, structure, or morphology at length scales down to the atomic level within the larger macroscopic framework of the system. In addition, 3D visualization provides the key third dimension to 2D projection images that are produced by most standard imaging techniques. Visualizing samples in three dimensions can be done nondestructively by imaging at many tilt angles using MicroCT or though similar tomography methods in a transmission electron microscope. Alternatively, it can be done destructively through slice and view methods using an ion beam in a FIB/SEM or by microtoming in the SEM. This talk will demonstrate the benefits of collecting these types of datasets using X-ray CT, SEM, and TEM and combining the different types of data to bridge the millimeter bulk to nanometer atomic length scales. This allows for precision targeting of a region of interest and detailed insight into the underlying structure of the material that influences its properties or response during testing or in real applications. 

Jennifer Gray
After Café: Basic Machine Learning Approaches to Simplify Image Analysis

This talk will introduce ImageJ (now called FIJI), an open-source image analysis software with a plugin that runs a machine learning algorithm (WEKA segmentation) and how this can be used to help with feature recognition and image segregation from any image-producing characterization technique (optical microscopy, SEM, TEM, AFM, etc.). I will provide examples where this software has been implemented to accelerate materials identification and improve statistical analysis of material concentration.

Maxwell Wetherington
After Café: Improving Device Quality and Reproducibility: Thin Film Adhesion Failures

Whether during initial development of a device, in the scale up for manufacturing, or during an established manufacturing process, engineers often need to address thin film adhesion failures.  This talk will highlight some of the methods available within the Nanofab and MCL to characterize adhesion failures and thus help identify the necessary process modifications required to increase device quality and/or reproducibility.  We will use an example of a failure that occurred at a metal contact layer on a passivation oxide to walk through the testing decisions that lead to an understanding of the root cause. 

Bob Hengstebeck
After Café: Studying Biological and Soft Matter Materials in Their Native Hydrated State

Biological materials are ~80 percent water and many materials are designed for use under aqueous and/or hydrated conditions. However, imaging /analyses of these systems are often performed after dehydration or freezing which can significantly alter the chemistry/structure from the native hydrated state. This talk will highlight several techniques available at Penn State that enable sample analysis in aqueous and/or controlled humidity environments with an emphasis on the additional information that can be obtained via these approaches. 

Sarah Kiemle
After Café: Characterization of Organic Thin Films and Surfaces

This talk will demonstrate some strategies for determining the structure and composition of organic thin films (less than 100 nm) with an emphasis on vibrational spectroscopy (FT-IR and Raman) and other select techniques such as AFM-IR and XPS. The pros, cons, and sampling considerations for each technique will be demonstrated using various examples from work performed in MCL and literature. The influence of film thickness, substrate type, and information needed on the decision of which analytical technique(s) to use will also be discussed.

Tawanda Zimudzi
After Café: 101 Ways to Measure Film Thickness

If you have a film you probably need to know its thickness. Film thickness measurements are important to everything from polymers to epitaxial 2D materials, but choosing the optimal technique is often not straightforward.  We will discuss some advantages and complications of several methods available at Penn State.  Techniques to be highlighted include:  X-ray methods, SEM, TEM, optical methods and other destructive and non-destructive techniques. Are there really 101 ways? Come find out.

Anthony Richardella
After Café: The Materials Characterization Lab Fall Kick Off

This will be an opportunity to learn about a variety of new capabilities, new expertise, and recommended best practices to maximize your usage of the MCL. Whether you’ve been using MCL for years, are looking to start using the lab soon, or are just curious about MCL resources this event is for you. All students, faculty, and staff are invited to attend. Excellent coffee will be provided.

Joshua Stapleton

After Café Fall 2024 Series

After Café: More than Just a Picture: Integrating CT into Research

Computed tomography (CT) is a non-destructive technique that is used to investigate the 3D structure in a wide range of materials of both biologic and synthetic origin, from manufactured metal parts to delicate insect specimens. With this technique, samples can be analyzed ranging from the size of cockroach antenna to a bear skull. Using image analysis software, visualization, processing, and quantification of internal and external features can produce eye-catching images, videos, and both quantitative and qualitative information, all with little to no harm to the sample. I will discuss different ways to utilize CT images in your research. 

Michelle Quigley, Assistant Research Professor, Institute of Energy and the Environment, Energy and Environmental Sustainability Laboratories, Center for Quantitative Imaging 

After Café: Rigor Matters: Accurate Analyses at Elevated Temperatures

Many areas of research characterize samples under standard conditions and attempt to extrapolate these results to temperatures or an atmosphere far from ambient.  Numerous non-ambient capabilities are available within MCL, these require careful planning and special hardware, but the data collected under non-ambient conditions can be invaluable.  Variable temperature accessories are perhaps the most convenient and commonly used for non-ambient analysis.  However, there are no accessories where the controller setpoint accurately reflects the sample temperature at the location being analyzed.  This talk will highlight two methods (FTIR and XRD) where the MCL has developed accurate and precise temperature calibration protocol. 

Jordan Meyet
After Café: Thermal Analysis Capabilities, Trade Offs, and Limitations

While thermal property analyses (TGA, DSC, SDT) are often considered routine techniques the published literature demonstrates that these are frequently misused or underutilized.  I will review the capabilities of the MCL thermal analysis suite to include highlighting the less obvious information that can be obtained with each technique.  Additionally, the tradeoffs associated with each technique will be discussed to provide practical guidance for choosing the proper analyses.  Finally, I will discuss what characterization should be performed prior to thermal analyses and introduce the “health check” tests which MCL routinely performs to ensure our instrumentation is operating properly. 

Dean Anderson
After Café: Evaluating Residual Stress and Strain States Using X-ray Diffraction Techniques

X-ray diffraction (XRD) techniques provide an attractive, nondestructive method to determine residual stresses by measuring atomic plane spacings in diffracting volumes and relating them to strain using the sin^2(psi) technique. This presentation will review the theory behind these calculations, identifying characteristics to look for during data analysis, a review of the advantages and limitations surrounding different experimental geometries, such as Bragg-Brentano and Grazing Incidence X-ray Diffraction (GIXRD), and an overview of MCL X-ray capabilities.  I will conclude with a short discussion about identifying when synchrotron x-ray capabilities may be appropriate for your specific experimental conditions. 

Taylor S. Wood – PhD Candidate, Materials Science and Engineering 

After Café: New Ways to Characterize Biological Samples using Scanning Transmission Electron Microscopy and Liquid Atomic Force Microscopy

Biological samples are often difficult to image due to their thickness, low contrast, and native hydrated state. We will discuss two different techniques available for analyzing these types of samples in Penn State's Material Characterization Lab, including scanning transmission electron microscopy (STEM) with energy dispersive spectroscopy (EDS), and liquid atomic force microscopy (AFM). Using a TEM with STEM-EDS capabilities, we can quickly acquire elemental maps at resolutions of less than 1 nm and sensitivities of less than one atomic percent. This provides many opportunities to answer important scientific questions related to the presence of metal atoms or other biologically relevant elements such as S, P, Ca, etc. in cells and biological structures in general. The other benefit of STEM imaging is the ability to image thicker samples with enhanced mass-thickness contrast as compared to TEM. This also makes the technique ideal for thick biological samples and removes some of the need for heavy metal staining in fixed samples. STEM imaging under cryo conditions or in liquids is also possible but poses significant challenges at high resolutions. However, we can use an AFM in liquid mode to capture the surface topography of biological samples with sub-nanometer-scale resolution in their native hydrated state. Since biological samples typically contain ~80 % water, removing water from or freezing a material can significantly alter its chemistry and structure and affect any analysis performed on that material. The capability of liquid AFM includes high-resolution imaging in fluid/hydrated samples, nanomechanical mapping, nanoindentation, high-speed AFM to molecular movements, and functionalized tip for molecular interaction. 

Jennifer Gray, Sarah Kiemle
After Café: Irreproducible or Low-Quality Data? How’s Your Prep?

Quality materials characterization always begins with proper sample preparation.  All too often individuals rush to analyze a sample without considering how its intrinsic state will influence results.  Considering sample roughness, thickness, critical feature size, or potential sources of contamination are just a few questions to ponder before jumping on that fancy analytical instrument.  The MCL has revamped its sample preparation laboratory with new expertise, equipment, and procedures.  I will highlight how to get started using this lab and provide general tips & tricks to improve the rigor and reproducibility of your work.

Bob Hengstebeck
After Café: Infrared Emission Characterization: Practical Approaches and Applications

Measuring the thermally emitted radiation of coatings, devices, and other materials has become an increasingly important topic as coatings are being applied to manage increasing heat loads on our infrastructure and as devices are pushed to higher limits. Characterizing the emissive property is relevant for developing technologies in energy conversion, imaging, and thermal management.  The MCL has recently developed methods to quantify the wavelength and intensity of the thermally emitted radiation from various samples ranging in size from 10’s of microns to the macro-scale. 

Tawanda Zimudzi, Linxiao Zhu