Progress on optical coatings deposited with dual rotatable magnetrons in a sputter up system

A turntable magnetron sputter system based on cylindrical magnetrons was used to investigate particles and uniformity profiles of different processes and coatings. The sputter system is based on a dynamic deposition employing a high-speed turntable and a double cylindrical pulsed magnetron discharge for the deposition of low and high index layers. Contamination by particles was investigated for different processes. Very clean coatings could be obtained for single layers as well as for multilayers. The thickness uniformity was investigated and optimized. In partial reactive mode, the oxygen partial pressure distribution is influenced by getter effects of the different surfaces in the sputter compartment, which makes the optimization of the uniformity more difficult. After suitable conditioning of the coater, a reproducible uniformity of 99.6% overall the substrate area was observed. The slope of the non-uniformity can be modified by changing the angle of the magnet bars of the magnetrons. The deposition of an optical multilayer system with around 60 layers and a total thickness of 8 μm was demonstrated and also a uniformity of 99.6% could be determined on different 200 mm glass substrates perpendicular and parallel to the arc of motion.