Progress in the production of CsI and diamond thin film photocathodes

The comparison between the quantum efficiency of photocathodes coated with thin CsI films obtained by thermal evaporation and, for the first time, by Ar ion-beam sputtering is reported. The sensitivity of photocathodes has been found to be strongly dependent on the morphology and roughness of the evaporated and sputtered CsI films. The effect of surface roughness on four different substrates has been investigated and is discussed. Preliminary measurement results on the photoeinissivity of diamond films are also given.