Changes in particle area measurements due to SEM accelerating voltage and magnification

Area of Science:

• Materials Science
• Polymer Science
• Microscopy

Background:

• Scanning electron microscopy (SEM) combined with digital image analysis offers a rapid method for measuring particle size and dispersion in polymer blends.
• Accurate morphological feature area measurements depend on understanding how SEM machine parameters influence image formation.
• The effect of accelerating voltage on SEM image analysis requires systematic investigation.

Purpose of the Study:

• To investigate the influence of accelerating voltage on area measurements of morphological features in SEM images.
• To evaluate the impact of accelerating voltage on particle size determination in polymer blends.
• To establish calibration strategies for SEM image analysis software based on accelerating voltage.

Main Methods:

• SEM imaging of standard metallic and polymeric samples, along with polymer blend samples.
• Systematic examination of area measurements under varying accelerating voltages.
• Calibration of off-line image analysis software based on assumptions of area variation or no area variation with accelerating voltage.

Main Results:

• Accelerating voltage critically influences area measurements in SEM images across various materials and magnifications.
• Higher accelerating voltages led to increased measurement errors for polymer samples, particularly at high magnifications.
• Increased electron beam energy causes deeper penetration, reducing signal resolution and degrading surface details.

Conclusions:

• Accelerating voltage is a key parameter affecting SEM image area measurements, especially for polymer samples.
• Lower accelerating voltages are recommended for imaging polymer samples to ensure clear surface detail.
• Accurate particle size measurements necessitate calibrating image analysis software to match the specific accelerating voltage and magnification used during image acquisition.