Thermionic Emitters
Cathodes operating in the thermionic regime are heated to high temperatures. Emission occurs when electrons have enough thermal energy to overcome the work function of the material from which the cathode is made.
APT is the world’s only commercial producer of CeBix® cathodes.
- We grow and fabricate our own high-quality, single-crystal LaB6 and CeBix® in-house using a process that produces the purest and lowest work function material commercially available.
- Long-term stability at high current densities, up to 20 A/cm2, making these cathodes ideal for small spot applications such as SEM, TEM, electron beam sterilization, surface analysis, and metrology as well as large current applications like x-ray generation, lithography, and additive manufacturing.
LaB6 and CeBix® features:
Note: With a slightly lower work function than LaB6, CeBix® cathodes generate higher currents at slightly lower operating temperatures. As a result, CeBix® sources have a slightly higher brightness and longer lifetime.
Featured Product: CeBix®(100) 2.8 mm Top Hat Cambridge MVM
- Low work function CeBix®(100), 2.5 eV
- Lifetimes of up to 5000 hours reported
- Lower volatility than LaB6
- Top-hat geometry on mini-Vogel mount (MVM)*
Sample Operation Data:
- Lowest heat setting where beam is stable, vacuum <10-6 torr
- Low work function - LaB6(100), 2.6 eV
- Lifetimes of up to 5000 hours reported*
- Lower volatility than LaB6
- Truncated crystal geometry on standard mini-Vogel mount (SMVM)
Sample Operation Data:
- Lowest heat setting where beam is stable, vacuum <10-6 torr
