The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
TY - CONF AU - Schumacher, M. AU - Jiang, X. AU - Vogel, M. ED - Schaa, Volker RW ED - He, Yuan ED - Li, Lu ED - Zhao, Ning TI - GaN-based Photocathodes for High Brightness Electron Beams J2 - Proc. of SRF2017, Lanzhou, China, July 17-21, 2017 C1 - Lanzhou, China T2 - International Conference on RF Superconductivity T3 - 18 LA - english AB - Prospective light sources requires photocathodes with high quantum efficiency (QE), long lifetime and minimized thermal emittance. One promising candidate meeting the aforementioned specifications is GaN. Due to its wide band gap (Eg = 3,4 eV), GaN can be excited by UV-light sources. Its thermal and chemical stability are added bonuses. In the framework of the present activity, the synthesis of GaN films on Si, Cu, Mo and Nb by means of rf magnetron sputtering is proposed. In this context, Ga, GaAs and GaN are suitable source material candidates, which are sputtered in a nitrogen/argon plasma discharge. The conductivity as well as the band-gap of the corresponding films can be modified by dopants like Mg and In, respectively. Standard materials science characterization techniques such as SEM, EDX, XRD or XPS are used to explore the growth mechanism of GaN alongside with a morphological and chemical examination. To assess and optimize the performance of the photocathode the abovementioned requirements are tested in an in-situ setup. In addition to the project outline, first experimental results of GaN coatings synthesized based on a GaAs source sputtered in pure N2 are presented. PB - JACoW CP - Geneva, Switzerland SP - 906 EP - 909 KW - ion KW - cathode KW - electron KW - target KW - experiment DA - 2018/01 PY - 2018 SN - 978-3-95450-191-5 DO - 10.18429/JACoW-SRF2017-THPB075 UR - http://jacow.org/srf2017/papers/thpb075.pdf ER -