Optimization study of direct morphology observation by cold field emission SEM without gold coating

Area of Science:

• Materials Science
• Electron Microscopy

Background:

• Gold coating is standard for imaging low conductive materials via scanning electron microscopy (SEM).
• However, gold coating can cause irreversible damage and distortion to sensitive materials.
• This limits detailed morphological analysis of certain low conductive samples.

Purpose of the Study:

• To investigate direct morphological characterization of low conductive materials using cold field emission scanning electron microscopy (FE-SEM).
• To establish optimal FE-SEM test conditions for various low conductive materials without gold coating.
• To avoid sample damage associated with traditional gold coating methods.

Main Methods:

• Direct characterization of hydroxyapatite, modified poly(vinylidene fluoride) (PVDF) fiber, and zinc oxide nanopillars using FE-SEM.
• Optimization of FE-SEM parameters including working signal modes, accelerating voltages, electron beam spots, and working distances.
• Comparative analysis of imaging results with and without gold coating.

Main Results:

• Successful direct morphological observation of low conductive materials was achieved using FE-SEM.
• Optimized test conditions varied for each material, highlighting the need for tailored approaches.
• FE-SEM without gold coating prevented distortion and damage, preserving material integrity.

Conclusions:

• Cold FE-SEM offers a viable alternative to gold coating for imaging low conductive materials.
• Careful selection and optimization of FE-SEM parameters are crucial for high-quality imaging.
• This technique enhances the study of delicate low conductive materials in materials science and related fields.