Engineered thin films by Pulsed Laser Deposition for thermionic applications
| Main Authors: | Bellucci Alessandro, Girolami Marco, Mastellone Matteo, Orlando Stefano, Mezzi Alessio, Kaciulis Saulius, Trucchi Daniele Maria |
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| Format: | Proceeding poster |
| Bahasa: | eng |
| Terbitan: |
, 2017
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/1118287 |
Daftar Isi:
- Thin films of borides (LaB6 and CeB6) and nitrides (CNx and AlN) were grown by ns (ArF, 193 nm) pulsed laser deposition (PLD) on refractory substrates selected by considering the thermal matching with the thin films in terms of thermal expansion and thermal and electric conductivities. Thin layers of these materials can act as efficient electron emitters for thermionic cathodes operating at high temperature (up to 2000 °C) due to their low work function, typically < 3 eV, and the high melting point. The electron emission was found to depend strongly on the film thicknesses. The physical properties of the thin films were optimized by varying the deposition temperature of the substrates, the target-to-substrate, the atmosphere (vacuum or Ar gas flow). X-ray spectroscopy (XPS) was used to investigate the properties of the deposited thin films. Ultraviolet PhotoSpectroscopy (UPS) and thermionic emission measurements were performed to evaluate the work functions of the emitting layers deposited on the selected substrates.