The enhanced robustness of TiN-armored copper photocathodes
Source abstract
Abstract
Titanium nitride (TiN) films were deposited by reactive sputtering in ultra-high vacuum, onto polycrystalline copper photocathodes, and analyzed by x-ray photoelectron spectroscopy (XPS) and quantum efficiency (QE) measurement before and after controlled oxygen exposure. Bare copper showed QE = 1.4 × 10−4, decreasing by three orders of magnitude after 10 L O2. TiN coatings reduced the initial QE by around one third to one-half but limited degradation to <1 order of magnitude after 50 L. Post-exposure XPS confirmed that oxidation was confined to TiN, indicating a substantial enhancement in photocathode material robustness.
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Research context
OpenAlex topics: Photocathodes and Microchannel Plates · Electron and X-Ray Spectroscopy Techniques · Gyrotron and Vacuum Electronics Research
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Department of Physics, University of Warwick 1 , Coventry CV4 7AL,
ASTeC, STFC Daresbury Laboratory 2 , Warrington WA4 4AD,
The Cockcroft Institute of Accelerator Science 3 , Warrington WA4 4AD,
Funding
Science and Technology Facilities Council · Engineering and Physical Sciences Research Council
References (31)
Show source-provided references
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