1. De-vacuum the Chamber : Release the vacuum to safely open the sample chamber.

Before loading the sample, it is necessary to release the vacuum inside the sample chamber. This is done by venting the chamber, allowing air to enter so that the chamber door can be safely opened. Ensure that the pressure reaches atmospheric levels before proceeding.

2. Load the Sample : Carefully place the sample on the stage while avoiding contamination.

Open the chamber and place the sample on the sample stage. The choice of sample depends on the type of analysis being performed :

• For imaging : The sample should be conductive or coated with a thin conductive layer (e.g., gold or carbon) if it is non-conductive to prevent charging effects.
• For compositional analysis (EDS/WDS) : The sample should be clean and dry to avoid contamination or interference in elemental detection.

Once placed, ensure proper alignment with the electron beam path.

3. Vacuum the Chamber : Close the chamber and initiate the vacuum system.

Close the chamber securely and start the vacuum pump to remove air and create a controlled environment for electron beam operation.

4. Wait Until Pressure Reaches ~10⁻⁴ Pa : Ensure a proper vacuum level is achieved for stable electron beam operation.

The chamber must reach an ultra-high vacuum (typically 10^-4 to 10⁻⁶ Pa) to ensure minimal electron scattering and to improve imaging resolution and signal-to-noise ratio. The required vacuum level depends on the microscope type :

• SEM : Usually operates in the range of 10⁻³ to 10⁻⁵ Pa.
• EPMA : Requires higher vacuum levels, often around 10⁻⁴ to 10⁻⁶ Pa for accurate quantitative analysis.
Wait until the required vacuum level is reached before proceeding.

5. Turn On the Electron Beam : Activate the electron gun to start imaging or analysis.

Once the desired vacuum level is achieved, activate the electron beam. Adjust the accelerating voltage based on the type of sample and the depth of analysis required :

• 1–5 kV : Suitable for surface imaging of delicate or beam-sensitive materials.
• 10–20 kV : Commonly used for general imaging and EDS analysis.
• >20 kV : Used for deeper penetration and enhanced X-ray generation in EPMA.

6. Magnify a Specific Location : Adjust magnification and focus on the area of interest.

Use low magnification to find the area of interest. Increase magnification gradually based on the level of detail needed :

• Low magnification (10x–500x) : Ideal for navigation and wide-area observation.
• For structural investigation : medium magnification (500x–5,000x) is utilized.
• High magnification (>5,000x) : Perfect for imaging at the nanoscale and fine structures.

7. Capture an Image or Perform Compositional Mapping : Choose between imaging (e.g., SE, BSE) or elemental analysis (e.g., EDS, WDS).

• For imaging : Choose between Secondary Electron (SE) mode for surface topography or Backscattered Electron (BSE) mode for compositional contrast.
• For compositional analysis : Use Energy Dispersive Spectroscopy (EDS) for qualitative or semi-quantitative elemental analysis, or Wavelength Dispersive Spectroscopy (WDS) for higher accuracy in quantitative analysis.
• For mapping : Perform elemental mapping to visualize element distribution across the sample.

8. Turn Off the Electron Beam : Safely shut down the beam after imaging or mapping.

Once imaging or analysis is complete, turn off the electron beam to prevent unnecessary exposure and potential damage to the sample or the instrument. Some of the things will be corrected by editing team.