Facilities
Scanning Tunneling Microscope (STM)
The lab has a scanning tunneling microscope (STM) system from Omicron Nanotechnology. This variable temperature microscope is housed in a custom-built, ultra-high vacuum (UHV) chamber outfitted with a number of features in interconnected, differential pumped vacuum chambers:
- Variable Temperature Scanning Tunneling Microscope
- Temperature Range: 25 K to 1500 K
- Scan Ranges: 10 mm x 10 mm x 10 mm (coarse), 12 µm x 12 µm x 1.5 µm (fine)
- In-situ exchange and storage of tip and sample
- Sample preparation and analysis tools
- Precision manipulator with heater for sample annealing
- Sputter ion source for cleaning single crystals
- Combination LEED/Auger to test crystalline quality and cleanliness
- Sub-monolayer source for low density atom deposition in-situ
- Load-lock for sample-tip introduction into vacuum while keeping the microscope under UHV conditions
Hyperthermal Energy Beamline and Scattering Chamber
We have a unique hyperthermal energy beamline and scattering chamber that was custom-built at Cornell University. Since being moved to Clemson, it has been substantially upgraded and rebuilt. For example, all of the diffusion pumps in the system were replaced with turbo pumps to create a cleaner, oil-free ultra-high vacuum (UHV) environment. The beam control and detection electronics have been upgraded. Other specifications of the beamline and chamber include:
- A Colutron ion source capable of producing low and hyperthermal energy atomic and molecular ion beams of alkalis, noble gases, and a wide range of reactive species.
- A Wien filter for mass-selection of produced beams.
- Multiple in-line Faraday cups for beam focusing and characterization.
- Differential pumping along the beamline, which allows for beam source pressures to rise as high as 10-5 Torr while the chamber pressure is maintained in the 10-11 Torr range.
- A two-tier UHV scattering chamber with surface analysis equipment mounted in the top tier (Auger spectrometer, Low Energy Electron Diffraction, Kelvin probe, alkali getters, residual gas analyzer, sputter gun) and scattered ion and neutral detectors mounted in the bottom tier on a rotating stage.