A compact two-electrode field-emission X-ray source for soft X-ray spectroscopy applications.

Area of Science:

• Physics
• Materials Science
• Spectroscopy

Background:

• Conventional thermionic X-ray tubes suffer from optical and thermal background noise.
• Developing compact, low-background X-ray sources is crucial for advanced spectroscopy.

Purpose of the Study:

• To design and characterize a compact, two-electrode field-emission X-ray source for soft X-ray spectroscopy.
• To suppress background noise and achieve stable, tunable X-ray output.

Main Methods:

• Utilized a blade-type tungsten cathode for field emission.
• Optimized cathode-anode spacing to 150 µm for stable operation up to 4 kV.
• Performed spatial intensity mapping and energy-resolved measurements using a silicon drift detector.

Main Results:

• Achieved stable operation at 400 µA and 4 kV in high vacuum (<1 × 10⁻⁷ mbar).
• Demonstrated tunable Bremsstrahlung continuum and reproducible Cu Lα emission at 927.7 eV.
• Obtained high signal-to-noise soft X-ray emission spectra (Ti Lα, O Kα).

Conclusions:

• The designed field-emission X-ray source effectively suppresses background noise.
• The compact, cost-efficient design is suitable for laboratory-scale soft X-ray spectroscopy.
• The source enables element-specific analysis and serves as a valuable tool for pre-beamline experiments.