Quanta 200F: SEM, ESEM, Lithography & Probe Station

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Quanta 200F
Quanta-200F-SEM.jpg
Instrument Type Microscopy, Lithography
Techniques SEM, ESEM,
E-beam Lithography,
Electrical 4-Point Probe Station,
Hot Stage, Cold Stage
Staff Manager Alireza Ghaffari
Staff Email alireza@caltech.edu
Staff Phone 626-395-3984
Reserve time on FBS
Request training via FBS User Dashboard
Lab Location B233 Steele
Lab Phone 626-395-5429
Manufacturer FEI (now Thermo Fisher)
Model Quanta 200F

Description

The Quanta 200F is a field emission gun (FEG) scanning electron microscope (SEM) that can also be operated in environmental (ESEM) mode, where a higher chamber pressure (0.1 to 27 mbar) allows for the imaging of e.g. biological samples without lysing cells. While the Quanta does not have an immersion lens for ultra-high-resolution imaging, as all other KNI SEMs do, this actually allows the Quanta's non-immersion objective lens to be optimally placed for "field-free imaging," making it the KNI's highest resolution SEM when operating outside of Immersion Mode. The Quanta is also equipped with an e-beam lithography system, a four-point electrical probing station, and a Hot/Cold Stage attachment. Its small chamber 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 the Quanta below.

SEM Applications
  • High-Resolution Imaging (Field-Free Mode aka Normal Mode)
  • Secondary Electron (SE) imaging with an Everhart-Thornley Detector (ETD)
  • Backscattered Electron (BSE) imaging with a solid-state Backscattered Electron Detector (BSED)
  • ESEM Mode for imaging biological samples using Large Field Detector (LFD) & Gaseous Secondary Electron Detector (GSED)
  • ESEM Mode for imaging highly non-conductive samples using LFD & GSED (the water vapor environment wicks away charge from sample); 500 μm clip-on aperture (to the bottom of the SEM column) is available for use in ESEM Mode to improve resolution
Other Applications
  • E-beam lithography with the Nanometer Pattern Generating System (NPGS) software
  • Hot & Cold Stage for observing a sample from -185 to 240 °C
  • Four-Point Electrical Probe Station for in situ electrical measurements

Resources

SOPs & Troubleshooting
Video Tutorials
Graphical Handouts
Presentations
  • SEM Essentials: Capabilities and Limitations of Scanning Electron Microscopy; and SEM Setup, Parameters and Theory for Successful Operations and Measurements
  • Scanning Electron Microscopy: Principles, Techniques & Applications (includes slides on ESEM, Lithography, Probe Station, Hot & Cold Stage)
Manufacturer Manuals
Simulation Software
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.
Sample Preparation
  • 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.
Order Your Own Stubs
  • Stubs used for mounting specimens are considered a personal, consumable item in the KNI. There are some old stubs at each SEM, yet you should buy your own so that you can keep them clean and available to you. There are many stub geometries and configurations, some of which will be right for you to purchase and keep with your other cleanroom items.
Guide to Choosing KNI SEMs & FIBs

Specifications

SEM & ESEM Specifications
  • Minimum Feature Size Resolved in SEM Mode: ~15 nm
  • Voltage Range: 0.2 to 30.0 kV
  • Current Range: "Spot Size" 1 to 7 (approximately 30 pA to 20 nA), with increments of 0.1
  • Apertures: 30 μm, 40 μm, 50 μm, 100 μm
  • Eucentric Height: 10 mm working distance (WD)
  • Stage Range: ±25 mm X & Y travel, 50 mm Z travel, -150 to 70° tilt, 360° rotation
  • ETD Grid Bias Range: -150 to 300 V
  • Ultimate Vacuum: 3e-7 mbar
  • ESEM Mode Pressure Range: 0.1 to 27.0 mbar (water vapor is used as chamber gas)
  • Minimum Feature Size Resolved in ESEM Mode: ~10 nm
Lithography with NPGS Specifications
  • Minimum Feature Produced: ~17 nm diameter dots & ~20 nm wide lines (via liftoff of 10 nm Ti on Si)
  • Shapes Available: Polygons (area dose), Single Pass Lines (line dose) & Dot Arrays (point dose) of any arbitrary shape
  • Writing Speed: 5 MHz
  • Digital-to-Analog Converter (DAC): 16-bit
  • Keithley 487 Picoammeter / Voltage Source is available for measuring beam current
Probe Station Specifications
  • Probe Station Manufacturer: Kammrath & Weiss
  • Parameter Analyzer: HP4145B Available (Manual), or bring your own
  • Keithley 487 Picoammeter / Voltage Source is available as a function generator
  • Probe station connectors rated up to 42 V, measure up to mA of current
Hot & Cold Stage Specifications
  • Temperature Range: -185 to 240° C
  • Stage is cooled by air that is itself cooled by flowing it through a liquid nitrogen heat exchanger
  • Stage is heated by a resistive heating element



Related Instrumentation in the KNI

Scanning Electron Microscopes (SEMs)
Lithography
Focused Ion Beam (FIB) Systems
Sample Preparation for Microscopy
Transmission Electron Microscope
Scanning Probe Microscopes