Industrial Scale 10µm W Coating of CFC Tiles for ITER-like Wall Project at JET
As a result of the R&D phase of the ITER-like wall project, Combined Magnetron Sputtering and Ion Implantation (CMSII) technique was selected for 10 µm W coating of approx. 1,000 CFC tiles for the new JET first wall. This technique involves simultaneous magnetron sputtering and high energy ion bombardment. A high voltage pulse discharge is super-posed over the magnetron deposition and by this way positive ions are accelerated, bombarding initially the substrate and then the coating itself during its growth. Based on this method, industrial equipment with a deposition chamber of F 800 x 750mm and 24 magnetrons was designed, manufactured and commissioned. The coating productivity is about 1m2 /week.Tungsten coatings with a thickness of up to 17µm and multilayer structures Mo/W/Mo/W with a thickness of ~25µm were produced and successfully tested at 100 pulses of 16.5 MW/m2 for 1.5s.