The overall aim is to identify a suitable material for photocathodes that produces a sufficiently high flow of electrons, despite limited oxidisation during operational life in low vacuum. The most promising strategies and materials were investigated. The strategy was, to use elements/alloys and their oxides that have a suitable UV LED emission work function and use an alloy with a low work function element. The materials selected for study were aluminium alloy 2014, aluminium alloy 2060, manganese, silver and pure titanium. Magnetron sputtering was used to create the thin films of materials for study. The photoelectron current generated when UV light was shone on the film was measured and recorded over 24 h in high and low vacuum. In conclusion, Mn and alloy 2014 produced poor results, alloy 2060 was an improvement, but did not produce a high enough photocurrent until more silver was added. Pure titanium results were the similar to alloy 2014. Other options such as nitride film and nickel were tested with little positive results. Recommendations’ are to explore alloy 2060 with more silver and titanium, look at copper, silver and investigate nitride films further.
|Date of Award||2023|
|Supervisor||John Allport (Co-Supervisor) & Vladimir Vishnyakov (Co-Supervisor)|