I have not received any additional information from 3M on Au-deposited films but Sheldahl has them.
Sheldahl has a series of gold deposited materials that can be used for the cathodes. These materials are normally specified as thermal barriers in satellites but can be used for the FDC cathodes. Part # 146437 (see below) is a standard product with 900 angstroms of Au on 25 micrometer Polyimide and can be delivered in 48 inches wide rolls. The left column below is for standard products (available) and they range from 8 to 127 micrometer Polyimide.
Let me know if this material is a good candidate for mass and then I can get additional information on deliveries, prices and samples.
Standard PCB processes may be used but there may be alternatives. Because the Au is very thin and most of the material is left on the foil after processing, there is the possibility of using CO2/YAG lasers for removing the material where not needed (between strips and traces) [laser printer?]. There are companies that do this and it would be great if this could be done on a roll of material. I am not advocating doing this for the prototype but it may be feasible as a long term solution.
Regards,
Fernando