We have scaled up and improved an established Plasma Assisted Reactive Magnetron Sputtering (PARMS) system for high-precision volume manufacturing of complex optical filters. The system can process batches of substrates having a diameter of up to 300 mm. By means of rotatable targets for the sputter deposition, a planetary drive system for the substrate holders, and an optical monitoring system for in-situ process control, deposition of highly complex optical filters can be performed. A comparison of coating results from this machine and its predecessor for substrates with a diameter of up to 200 mm is shown. Due to the improvements, the layer non-uniformity of oxides could be reduced from ±0.5 % down to about ±0.15 % compared to the predecessor, even though the substrate diameter was increased. Using the optical monitoring system an optical band pass filter was deposited on Ø300 mm glass wafers demonstrating the capability of the machine for production with high throughput and yield.
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