• W. Kaabi, A. Variola
  LAL, Orsay
• A. Brinkmann
  DESY, Hamburg
• G. Keppel, V. Palmieri
  INFN/LNL, Legnaro (PD)
• I. Montero
  CSIC, Madrid

LAL-Or­say is de­vel­op­ing an im­por­tant ef­fort on R&D and tech­nol­o­gy stud­ies on RF power cou­plers for su­per­con­duc­tive cav­i­ties. One of the most crit­i­cal com­po­nents of those de­vices is the ce­ram­ic RF win­dow that al­lows the power flux to be in­ject­ed in the coax­i­al line. The pres­ence of a di­elec­tric win­dow on a high power RF line has a strong in­flu­ence on the mul­ti­pactor phe­nom­e­na. The most im­por­tant method to re­duce the mul­ti­pactor is to de­crease the sec­ondary emis­sion yield of the ce­ram­ic win­dow. Due to its low Sec­ondary elec­tron Emis­sion Yield (SEY), TiN thin film is used as a mul­ti­pactor sup­pres­sor coat­ing on RF ce­ram­ic cou­pler win­dows. In this frame work, TiN de­po­si­tion was made by mag­netron re­ac­tive sput­ter­ing. XPS and XRD anal­y­sis were per­formed to con­trol the film com­po­si­tion and stoe­chiom­e­try. Coat­ing thick­ness was op­ti­mized so that the TiN coat­ing ef­fec­tive­ly re­duces the SEY but does not cause ex­ces­sive heat­ing, due to ohmic loss. For this pur­pose, SEY mea­sure­ments on cov­ered and un­cov­ered TiN Alu­mi­na sub­strates, mul­ti­pactor level break­down on TiN coat­ed Cup­per sub­strates and RRR mea­sure­ments were per­formed for dif­fer­ent de­posit thick­ness­es.