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Preparing a Celadonite Electron Source and Estimating Its Brightness
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Stable field-emission from a CeB6 nanoneedle point electron source.
Shuai Tang1, Jie Tang1,2, Yimeng Wu1,2
1National Institute for Materials Science, Tsukuba, Ibaraki 305-0047, Japan. tang.jie@nims.go.jp.
Nanoscale
|October 12, 2021
Summary
A novel cerium hexaboride (CeB6) nanoneedle was fabricated for electron emission. This stable field emission source is ideal for microscopy applications.
Area of Science:
- Materials Science
- Condensed Matter Physics
Background:
- Field emission electron sources are crucial for various applications, including microscopy.
- Developing stable and efficient electron emitters remains a key challenge.
Purpose of the Study:
- To fabricate a single CeB6 nanoneedle structure.
- To evaluate its field emission characteristics and potential for microscopy.
Main Methods:
- Focused Ion Beam (FIB) fabrication of a single CeB6 nanoneedle.
- Characterization of field emission properties, including current stability and electric field requirements.
Main Results:
- Fabricated a sharpened CeB6 nanoneedle with a tip radius of ~10 nm.
- Achieved low turn-on electric field (1.6 V nm-1) for 50 nA emission current.
- Demonstrated exceptional current stability (1.6% fluctuation over 16 hours) at 10-7 Pa vacuum.
Conclusions:
- CeB6 nanoneedles exhibit excellent field emission properties due to their sharp tips and low work function.
- The nanoneedle structure enhances stability by reducing gas adsorption/desorption.
- CeB6 is a promising material for practical point electron sources in microscopy.
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