Sirion: SEM & EDS
The Sirion is a field emission gun (FEG) scanning electron microscope (SEM) equipped with an immersion lens for imaging sub-10 nm features (so-called "ultra high resolution mode," UHR). While it is the KNI's oldest SEM, it is also a very steady instrument, offering a lower-cost alternative to similar high-resolution imaging that is available on the newer Nova 600 & Nova 200 NanoLab platforms. The smaller Sirion chamber also allows for fast pump and vent times, which makes this SEM very useful for quick inspection. See a full list of training and educational resources for this instrument below.
- Ultra-High-Resolution Imaging (Immersion Mode aka UHR Mode)
- High-Resolution Imaging (Field-Free Mode aka Normal Mode)
- EDX Mode Imaging (reduces background signal on EDS spectra)
- Secondary Electron (SE) & Backscattered Electron (BSE) Imaging
- Everhart-Thornley Detector (ETD) & Through-the-Lens Detector (TLD)
SOPs & Troubleshooting
- Getting Started | Basic SEM Alignment
- Astigmatism Correction (Details | On Right-Angle Features | Stigmator Alignment)
- Eucentric Height: What it means, When to use it & How to get there
- Adjusting TLD Voltage to Capture SE vs. BSE Signal
- Scanning Electron Microscopy: Principles, Techniques & Applications (includes slides on EDS)
Calibrate Measurements with NIST Standard
- The KNI has a NIST-traceable standard against which SEM measurements can be compared. See Slides 54-55 of the SEM Presentation for details. Ask staff for help finding and using the standard in the lab.
- CASINO Electron Beam Simulation Software – simulate e-beam/specimen interactions (very useful for EDS)
- Use the Carbon Evaporator to make non-conductive samples conductive by applying 2-10 nm of evaporated carbon.
- Use the O2/Ar Plasma Cleaner to remove hydrocarbons from the sample surface to avoid creating dark contamination spots on your features while imaging them.
Stubs for specimen mounting
- Stubs used for mounting specimens are considered a personal, consumable item in the KNI. There are some stubs at each Microscope which can be used by any KNI microscopy user. You can also buy your own stubs so that you can keep them clean and available to you. There are many stub geometries and configurations. If you chose to buy your own stubs, please show them to the staff microscopist prior to using them: some stubs including stubs with copper clips have large height differences and can only be used safely in specific operating conditions.
Guide to Choosing KNI SEMs & FIBs
- Minimum Feature Size Resolved: ~7 nm
- Voltage Range: 0.2 to 30.0 kV
- Current Range: "Spotsize" 1 to 7 (approximately 30 pA to 20 nA), with increments of 1
- Apertures: 30 μm, 40 μm, 50 μm, 100 μm
- Eucentric Height: 5 mm working distance (WD)
- Stage Range: ±25 mm X & Y travel, 50 mm Z travel, 0-45° tilt, 360° rotation
- ETD Grid Bias Range: -150 to 300 V
- TLD Bias Range: -100 to 150 V
- Ultimate Vacuum: 3e-6 mbar
Related Instrumentation in the KNI
Scanning Electron Microscopes (SEMs)
- Nova 600 NanoLab: SEM, Ga-FIB, GIS & Omniprobe
- Nova 200 NanoLab: SEM, EDS & WDS
- Sirion: SEM & EDS
- Quanta 200F: SEM, ESEM, Lithography & Probe Station
Focused Ion Beam (FIB) Systems
Sample Preparation for Microscopy
- Carbon Evaporator (Leica EM ACE600) to make samples conductive
- Oxygen & Argon Plasma Cleaner (Tergeo Plus ICP- & CCP-RIE) to remove hydrocarbons from surface