High-power X-ray generators

Conventional high-power X-ray generators have the disadvantage of huge corrosion effects in the X-ray emitting palladium anode. The damage turns out to be caused by diffusion of hydrogen in the palladium target, deforming its microstructure. This hydrogen can be traced back to the X-ray induced dissociation of the cooling water, flowing along the outside of the anode. To avoid these effects, the target is externally coated with e.g. Pd3Sn. The inside of the target surface and a major extent of the palladium anode remain virtually unaffected. The desired palladium emission characteristic of the anode is thereby preserved. The resulting long-life properties enable application in high-power X-ray lithographic systems. (G.J.P.)