Magnetron sputtering

The technology

Of all the coating technologies used on plate glass today, sputtering has achieved the greatest economic importance by far. More than 100 million m² of plate glass are coated worldwide using this technology today, with a continuing rising trend. Magnetron sputtering on inline coating systems has established itself as the standard technology for the production of low-E and sun control film systems. Such sputtering systems process substrates in the ribbon format of 3.21 x 6.00 m² with cycle times as low as 45 s. Operated in 3 shifts with one maintenance shift per week, such a system coats up to 12,800 substrates. This results in a maximum productivity of approximately 12 x 106 m²/a. Magnetron sputtering is based on the principle of cathode evaporation in low-pressure glow discharges. Ions are accelerated onto the cathode in the cathode drop so that a collision cascade is triggered in the cathode, leading to the release of target material. With the magnetic pressure increase method, the working pressure of the sputtering process can be reduced from approximately 5 Pa without a magnetic field to around 0.1... 1 Pa.