Electron and X-ray Microscopy

We achieve unprecedented understanding of materials properties at the nano to atomic scale with high spatial, energy, and temporal resolution.

Low-dose atomic-resolution image of organic molecules on a single-wall carbon nanotube.

Understanding the microscopic structure of materials is essential for determining their properties and for the creation of new, useful devices. For decades, electron and X-ray microscopies have been used to look inside matter. Electron microscopes can now resolve single atoms buried within structures, while X-ray microscopes can discern minute lattice distortions in materials. Center for Nanoscale Materials (CNM) researchers with deep expertise in these two areas work closely together to create the most powerful images of material structures and dynamics.

Combining our emerging ultrafast microscopy capabilities with our newly developed capabilities of aberration-corrected atomic-resolution dynamic STEM imaging and CL spectroscopy, X-ray fluorescence spectroscopy, in-situ liquid/gas/heating/cooling, hundredths-of-picometer strain sensitivity in two and three dimensions, and artificial intelligence enabled image reconstructions – our goals are to characterize, and ultimately to control, the functionalities of materials from the atomic scale to the device level. This vision encompasses the five scientific themes of the CNM: Quantum coherence by design; Interfaces, assembly and fabrication for emergent properties; Ultrafast dynamics and non-equilibrium processes; AI/ML Accelerated analytics and automation; and Nanoscale discovery for a sustainable energy future.

Nanoscale Dynamics is a particular area of focus for the Electron and X-ray Microscopy group - our ultrafast electron microscope is open for users now and can provide sub-nm, sub-ps and sub-eV spatial, temporal, and energy resolutions to understand transient phenomena of materials, soon to be complemented by two aberration corrected dynamic STEM instruments. The focus in the X-ray microscopy effort is two- fold: (i) to develop time-resolved pump-probe Bragg diffraction microscopy capabilities at the Hard X-ray Nanoprobe (HXN) for operando picosecond/nanoscale studies of dynamic phenomena in classical and quantum materials harnessing the unique per-bunch brightness of the APS-Upgrade; and (ii), to extend Bragg ptychographic imaging into the dynamical diffraction regime using ML/AI enabled approaches for full 3D visualization of deep defects in quantum and classical materials microns from surfaces -all together creating unique visualization tools for the dynamic manipulation of nanoscale phenomena in space and time.

Key capabilities

Hard X-ray Nanoprobe, located at APS Sector 26
Ultrafast Electron Microscopy (UEM)
TFS Spectra 200 STEM
TEM/STEM: FEI Talos S/TEM
JEOLJEM-2100F Field-Emission-Gun Transmission Electron Microscope
FEI Quanta 400F ESEM
Hitachi S-4700-II SEM
JEOL IT800HL SEM

Group capabilities

Dynamic Aberration Corrected Microscope (Both probe and image correction). Equipped with IDES luminary system and DE Celeritas

Scientific Contact: Yuzi Liu

FEI Quanta 400F Scanning Electron Microscope. This is a high-resolution environmental and variable-pressure SEM.

Scientific Contact: Jianguo Wen

JEOL JEM-2100F Field-emission Transmission Electron Microscope. This instrument provides high-resolution imaging of nanoscale structures in bright- and dark-field modes. The point and line resolutions of the microscope are 0.23 nm and 0.1 nm, respectively. The range of the selected area camera lengths allows the user to obtain electron diffraction patterns that can give information about the ordering in thin films and structures assembled from atoms and nanosized particles. An energy-dispersive X-ray spectrometer allows simple and integrated acquisition of the composition of local regions of the sample. The microscope is capable of automated three-dimensional structural analysis. A Gatan Imaging Filter (GIF) System expands the capabilities to energy-filtered TEM and to electron energy-loss spectroscopy (EELS). The GIF system also enables chemical mapping and bonding state information acquisition.

Scientific Contact: Yuzi Liu

The joint CNM/APS Hard X-ray Nanoprobe (HXN) facility at APS beamline 26-ID delivers a hard X-ray beam tunable over the 6–12 keV spectral range and focused to 25 nm onto the sample. This X-ray energy range is ideal for probing crystalline thin films, devices and interfaces, many inner-shell electronic resonances, and mapping most elements in the periodic table. The HXN uses interferometric control to maintain relative positional drift of the focusing optics and sample less than 10 nm/h. The working distance between the X-ray focusing optics and the sample is typically a few mm, enabling a variety of in-situ and operando experiments with variable temperature, applied electric and magnetic fields, and liquid and gaseous environments. A heating/cooling specimen stage supports variable temperature experiments with the HXN over a temperature range of 100–525 K with a step-size of 0.01K and stability of 0.005K. The HXN supports scanning nanodiffraction, Bragg ptychography (5 nm resolution), and multimodal chemical and structural nanoimaging (approximately 30-nm resolution).

Scientific Contact: Martin Holt

Hitachi S-4700-II Scanning Electron Microscope. This is a high-resolution, high-vacuum SEM.

Scientific Contact: Rachel Koritala

The JEOL IT800HL SEM provides high resolution imaging of a variety of samples. The SEM is equipped with several detectors and analytical tools, including secondary and backscatter electron detectors, energy dispersive spectroscopy, scanning transmission detection, low vacuum mode, and electron backscatter diffraction system. Gentle beam mode allows for improved resolution with insulating or beam-sensitive samples.

Scientific Contact: Rachel Koritala

FEI Talos F200X TEM. This is a scanning/transmission electron microscope with an X-FEG field-emission gun and specializing in high-resolution STEM imaging. It is equipped with a Super X energy-dispersive spectrometer (EDS) allowing for fast and precise EDS mapping.

Scientific Contact: Thomas Gage

This Thermo Fisher Spectra 200 scanning/transmission electron microscope (S/TEM) is under installation and expected to open to users in the first quarter in 2023. It has a cold-field emission gun (C-FEG with 0.3 eV energy resolution), a Cs probe corrector for sub-0.1 nm resolution HAADF imaging; a Super X energy-dispersive spectrometer (EDS) for atomic resolution EDS mapping, Gatan energy-filter imaging and electron energy loss spectroscopy (EELS); a bi-prism; and an EMPAD for 4D-STEM.

Scientific Contact: Yuzi Liu

The UEM’s application is for investigating ultrafast (sub-picosecond) structural and chemical dynamics in materials at the nanoscale using electrons. The instrument is based on a JEOL JEM2100PLUS electron microscope and Altos Photonics lasers and has the following features: (a) a tunable femtosecond laser with a high repetition rate, (b) multiple routes to produce a pulsed electron beam, (c) a synchronous laser-pumped, pulsed transmission electron microscope that is outfitted with high-sensitivity cameras and electron energy filtering. This tool opens the door to an area of scientific understanding not available with any standard electron microscope, namely, the understanding of fast (sub-picosecond to nanosecond) dynamics and short-lived metastable phases in materials with sub-nanometer spatial resolution. This key analytical tool can deliver insights on ultrafast structural and chemical changes to a wide range of systems.

The technical specifications are:
Temporal resolution: approximately 1 ps
Spatial resolution: approximately 1 nm
Energy resolution: approximately 1 eV
Pump laser wavelengths: 515 nm, 325-450 nm, 650-900 nm, 1030 nm, and 1200-2000 nm
Repetition rate: 10-500 kHz (fs laser), 1-100 kHz (ns laser)

Scientific Contact: Haihua Liu and Thomas Gage

This platform accommodates site-specific TEM sample preparation, 3D data acquisition, nanofabrication and manipulation, and other advanced uses. Simultaneous electron and ion scanning offers unique imaging and fabrication opportunities.

Scientific Contact: Yuzi Liu