Equipment & Techniques
Omicron 4-Point Nanoprobe system (more images and details coming soon).
Omicron Nanotechnology 4-Point Nanoprobe system capable of performing scanning electron microscopy (SEM), scanning Auger spectromicroscopy (nanoSAM), and low energy electron diffraction (LEED).
The sample stage utilizes the common "flag" style sample holders and can be cooled to below 120K with liquid nitrogen under the SEM column. Samples can be transferred to the preparation chamber for sputtering, annealing (>1000K), deposition, and LEED. The system can accommodate numerous samples at a time and is designed for high sample throughput.
Elmitec LEEM V (more images and details coming soon).
Elmitec LEEM V system for in-situ low energy electron microscopy (LEEM), photoemission electron microscopy (PEEM) and micro-low energy electron diffraction (u-LEED).
The Elmitec LEEM V is a field-emission low energy electron microscope for in-situ microscopy of dynamic surface processes. The microscope is capable of micro-low energy electron diffraction (u-LEED). In contrast to conventional LEED optics that average over a large area of the sample u-LEED can yield diffraction patterns of different micron-sized regions of the sample surface. While imaging the sample can be heated to 1500K and exposed to certain gases at pressures up to 10-3 Torr. The system has a separate preparation chamber that includes a load lock, sputter ion gun, and an additional heating stage. In LEEM the resolution is 5.5nm on Pb on Mo(100) and in PEEM the resolution is 9.5nm on Pb on Mo(100).
In contrast to other imaging techniques such as scanning probe microscopy, scanning electron microscopy, or transmission electron microscopy, this full-field microscope allows for real-time imaging of the sample without the need to raster across the surface. Unlike TEM and SEM that can cause beam damage on the sample due to high accelerating voltages, the electrons in LEEM are slowed down to a few eV or a few tenths of an eV before they reach the surface of the sample or can even be reflected off the surface with little interaction (negative potential). One of the most common uses of the instrument is to study real-time film growth, changes in the phase or crystallinity, or work function changes of samples under various conditions (pressure, temperature, environment, etcetera).
We are in the process of adding an Auger electron spectrometer to the system for further analysis. We also have plans of adding IRRAS or RAIRS capabilities that can be performed simultaneously with LEEM.
microReactor (future work / under construction)
This instrument will be utilized for the catalytic evaluation of 2D single crystals. Briefly, the unit consists of several mass flow controllers, rotary valves, gas-independent pressure gauges, pumps, heating stage, and a GC/GCMS for detection and quantification. The GCMS is an Agilent 7890 GC with both a mass spectrometer and thermal conductivity detector (TCD) as well as two split/splitless injectors that can be cryogenically cooled.
s-SNOM and nano-IR (future work)
We are planning to purchase a scattering-type scanning near-field optical microscope and nano-IR system that utilizes an AFM probe to acquire an IR spectrum of a ~10-20nm region of the surface.
Elmitec AC-LEEM III / XPEEM Endstation - ESM-2 Beamline (21-ID-2)
Aberration-corrected LEEM/XPEEM. Energy range 15-1500 eV.