Patent ID: 8222157

Claim:
A method of processing a semiconductor substrate comprising: supporting a semiconductor substrate in the plasma processing apparatus comprising: a bottom electrode optionally coupled to a first radio frequency (RF) source; a chuck positioned on said bottom electrode and adapted to generate a clamping force on a substrate mounted thereon; an upper electrode optionally coupled to the first RF source and positioned over said chuck, said bottom electrode and upper electrode being adapted to generate plasma in a space between the upper and bottom electrodes by supplying RF power to one of the electrodes by the first radio frequency (RF) source; a dielectric support ring surrounding the upper electrode; and a plurality of coil units spaced apart in a circumferential direction and mounted on said dielectric support ring, each of said coil units including a ferromagnetic core positioned on and parallel to a radial line originating from a center of said dielectric support ring and a first coil wound around said ferromagnetic core and coupled to a second radio frequency (RF) power source, each first coil extending parallel to the radial line and connected in series with each other wherein said coil units generate, upon receiving RF power from said second RF power source, electric and magnetic fields that confine said plasma; generating plasma in the space between the upper and bottom electrodes; and processing the semiconductor substrate with the plasma.