PLANAR MAGNETRON WITH ADDITIONAL PLASMA-CONFINEMENT

This paper reports on a small, planar, circular magnetron with target of 60 mm diameter for low pressure sputtering of thin films. A stable discharge can be sustained in the case when the plasma confinement near the target surface is improved by means of an assembly of permanent magnets placed above the target. It is shown that the polarity of permanent magnets plays a crucial role in the plasma confinement The plasma confinement is characterized by measurements of the pressures for the sputtering discharge ignition p(st) and extinction p(ex). The discharge characteristics of this magnetron were measured in detail. Also, it is shown that the efficiency of the target utilization increases considerably at pressures below 0.1 Pa. At argon pressures of about 0.05 Pa and lower, target utilization greater than 80% can be reached.