Abstract: A wafer processing chamber 11 includes a wafer support 12, a dielectyric window 13 and coaxial coils 15 and 16 located outside the dielectric window 13 for inducing a plasma within the chamber. A variety of coil/dielectric windows are described together with protocols for their control.

Abstract: Plasma processing apparatus frequently incorporates an antenna fed from a power supply and in this invention a power supply feeds a conventional matching circuit (10), which in turn is connected to the primary (11) of a transformer (12). The antenna (15) is coupled across the secondary winding (13) of the transformer (12) and that winding is tapped to ground at (16). This creates a virtual earth (17) near the mid point of the antenna (15) significantly reducing the variation, along the length of the antenna, in the power supplied to the plasma.

Abstract: There is disclosed a method and apparatus for etching a substrate. The method comprises the steps of etching a substrate or alternately etching and depositing a passivation layer. A bias frequency, which may be pulsed, may be applied to the substrate and may be at or below the ion plasma frequency.