Scanning electron microscopy (SEM) is an electron microscopy technique in which a tiny beam of electrons is scanned across the surface of a sample. A high-resolution 3D image of the sample surface is generated when the electron beam strikes a metal-coated specimen and the electrons reflected (back-scattered) or given-off (secondary electrons) are detected.
Equipment:
Hitachi SU8700 SEM (Ultrahigh resolution SEM/Variable Pressure SEM with a field emission gun)
Zeiss XB350 SEM (Ultrahigh resolution SEM with a field-emission gun)
Tousimis Critical Point Dryer, Cressington Sputter Coater, Leica ACE600 coaters to prepare samples for SEM
Sample Preparation:
Hitachi SU8700 variable pressure SEM mode – samples are not required to be coated
Hitachi SU8700 FESEM and Zeiss XB350 FESEM – samples are required to be dehydrated and coated
- Fixation
- Dehydration
- Critical point dry (complete dehydration)
- Mounting
- Sputter coating (with Gold and/or Platinum)
- SEM
Comparison of High-resolution SEM and VP SEM
| Zeiss XB350 Field emission (FE)-SEM | Htachi SU8700 Field emission (FE)-SEM | Hitachi SU8700 Variable pressure (VP)-SEM | |
| Resolution | Ultrahigh up to 0.7 nm | Ultrahigh up to 0.6 nm | |
| Electron Gun | Field emission schottky gun - very bright, tiny spot size, low voltage | Field emission schottky gun - very bright, tiny spot size, low voltage | Field emission schottky gun - very bright, tiny spot size, low voltage |
| Vacuum | Ultrahigh | Ultrahigh | Low 5-300 Pa |
| Sample Condition | Dry, coated with metal | Dry, coated with metal | Semi dry sample can be viewed No sample preparation is needed |
Publications:
Megdich, A., Habibi, M., Laperrière, L., Li, Z., & Abdin, Y . (2025). Advanced nanocomposites for 4D printing: High-performance electroactive shape memory polymers for smart applications. Applied Materials Today, 44, 102702. https://doi.org/10.1016/j.apmt.2025.102702
Yavarinasab, A., He, J., Mookherjee, A., Krishnan, N., Pestana, L. R., Fusco, D., Bizzotto, D., & Tropini, C. (2025). Electrogenic dynamics of biofilm formation: Correlation between genetic expression and electrochemical activity in Bacillus subtilis. Biosensors and Bioelectronics, 276, 117218. https://doi.org/10.1016/j.bios.2025.117218
Wang, S., Yu, Z., Sun, X., Panahi‐Sarmad, M., Yang, P., Zhu, P., Zhu, Y ., Liu, H., & Jiang, F. (2024). A Universal Strategy to Mitigate Microphase Separation via Cellulose Nanocrystal Hydration in Fabricating Strong, Tough, and Fatigue‐Resistant Hydrogels. Advanced Materials, 37(7), 2416916. https://doi.org/10.1002/adma.202416916