Dual Magnetron Sputtering – Sputter Rate and Efficiency for Different Power Supply Designs and Frequencies
(Room Exhibit Hall A)
30 Apr 19
2:30 PM
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4:00 PM
There is a number studies on the influence of frequency and the type of power supply in dual magnetron sputtering. The results are not consistent, partly only a minor influence of the frequency was found, but partly a significant decrease of the rate with the frequency was reported. In this article we investigate this question under conditions relevant to large-area coating. In a test chamber, Jumbo-size magnetrons (planar and tube) with a length of 3.75 m are used. The rate is measured using a quartz crystal rate monitor. This study also compares the rate per mains input power, the magnitude which determines the process economy. A comparison of a bipolar (120 kW) and an MF generator (150 kW) shows that at low frequencies around 20kHz the bipolar generator can bring about 10% higher sputtering rates at the same input power. At higher frequencies, as they are often chosen to minimize arcing, the rates are comparable. In addition to physical effects that lead to some decrease in the rate from about 50kHz, the different internal losses of the power supplies and their behavior under partial load (which is common in practice) also play an important role and are discussed.