PROGRESS ON GROWING A MULTI-ALKALI PHOTOCATHODE FOR ERL AT BNL

K2CsSb is a robust photocathode capable of generating electron beams with high peak, high average current and low thermal emittance. During the last two years, a great improvement in the design and fabrication of a reliable deposition system suitable for K2CsSb cathode growth and its insertion into BNL high current ERL SRF gun has been achieved. A standard procedure for the growth of multi-alkali cathodes combined with another procedure to transport these cathodes into the SRF gun was developed. The first cathode is planned to be grown on a copper insert and mounted into the 704 MHz gun. In this article, we will describe the progress of cathode growth and transport for ERL project. In particular, effect of excimer laser exposure and the cathode growth on Ta will be included.