2024-12-20 to 2025-01-02: Reduced Holiday Operations
Dear Birck Research Community,
The Purdue winter recess begins effective Friday afternoon December 20th and concludes Thursday morning, January 2. The university is officially closed during this time. As we have done in past years, the Birck Nanotechnology Center will remain available for research but will be unstaffed and hazardous gasses will be unavailable. Lab work may otherwise proceed, though any fume hood work must be done with someone else present in the same laboratory or cleanroom bay (the "buddy" system). Click the link above to get more detail about equipment conditions and rules.
Refer to the Material and Process Compatibility page for information on materials compatible with this tool.
Equipment Status: Set as UP, PROBLEM, or DOWN, and report the issue date (MM/DD) and a brief description. Italicized fields will be filled in by BNC Staff in response to issues. See Problem Reporting Guide for more info.
| Status | Up |
| Issue Date and Description | |
| Estimated Fix Date and Comment | |
| Responding Staff | Alejandro Alcaraz |
iLab Name: Hitachi S-4800 Field Emission SEM
iLab Kiosk: Purdue Electron Microscopy Facility
FIC: Rosa Diaz
Owner: Alejandro Ramirez
Location: BRK 1235
Maximum Wafer Size: 4"/100 mm
Overview
General Description
The S-4800 Cold Field Emission SEM combines the outstanding high-resolution performance capabilities to offer superb resolution of ~ 2.0 nm at 30 kV. The equipment is equipped with a EDX detector for the detection of chemical elements on your sample at higher voltages.
Specifications
- Accelerating voltages are from 500 V to 30 kV
- Resolution ~ 2.0 nm at 30 kV
- A choice of specimen stage: 4", 2" and 1" wafer and cross section
- An objective lens design with "Super ExB Filter" technology. The Super ExB Filter collects and separates the various components of pure SE, compositional SE and BSE electron signals.
- A specimen stage for large sample applications with 110mm x 110mm stage movement and computer controlled 5 axes motorization with graphical interface software.
- New Super ExB Filter Technology
- EDX and STEM detectors
- 200mm Specimen Diameter
- 5 Axis Motorized Eucentric Stage
- Advanced Dry Vacuum System
Technology Overview
Hitachi S-4800 is an electron beam microscope, that accelerates an electron beam in a vacuum environment to interact electrons with the sample of interest.
Sample Requirements and Preparation
Samples should be conductive to maximize sample imaging. With conductive samples features of 10nm can be observed with 5kV. Nonconductive samples can still be imaged, but not small features, limiting smallest resolutions to hundreds of nm, even microns, at low beam voltages (1-5kV). Non-conductive samples can become conductive if they are coated with Carbon, Au-Pd, or Silver paint.
Standard Operating Procedure
Questions
How should my sample be mounted?
Make sure your sample is below the maximum height (exchange chamber height), and the screw is not below the holder base.
How to avoid charging in my sample?
Reduce the voltage used or make your sample conductive by applying a conductive coating (C or Au/Pd).
What is the proper voltage to select?
The voltages selected can be between 500V and 30kV. The Voltage selected depends on your sample material. If your sample is a polymer, use low voltages, (<10kV); if your sample is a ceramic or metal, you can use higher currents. You may expect an interaction between the electron beam and your sample, which may leave an observation (contamination or degradation) box, the higher the current, the stronger it will be.
What is the proper current to select?
Start with medium currents, if the current increases, you may have more signal represented in brightness; if the current decreases, you may be able to observe areas with a smaller resolution, but with lower signal.
Troubleshooting
If the computer freezes, you can restart it by pressing Ctrl+Alt+Del for 10 seconds.
Be careful when loading your sample through the Exchange Chamber. Make sure the sample is mounted correctly.
If there is a problem with the beam or SEM, please contact the Electron Microscopy Staff.
References
- Inkson, B. J. "Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) for materials characterization." Materials characterization using nondestructive evaluation (NDE) methods. Woodhead Publishing, 2016. 17-43.
- Sharma, Surender Kumar, et al., eds. Handbook of Materials Characterization. Springer International Publishing, 2018.
- Reimer, Ludwig. Scanning electron microscopy: physics of image formation and microanalysis. Vol. 45. Springer, 2013.