Patent ID: 6463875
Filing Date: 2002-10-15
Classification: H01J

Abstract:
An apparatus for generating an inductively coupled plasma, the apparatus comprising:a plasma reaction chamber having a window forming an electro-magnetic field path into the chamber and a process gas supply configured to introduce process gas into the chamber; a radio frequency antenna comprising at least first and second antenna segments disposed outside said plasma reaction chamber; and a radio frequency source coupled to the antenna segments and configured to resonate radio frequency currents in the antenna segments, a first input capacitor connected to the first antenna segment and a second input capacitor connected to the second antenna segment; the first and second antenna segments being tied together and terminated to ground through an impedance; wherein electro-magnetic fields induced by the radio frequency currents are effective to pass through the window and excite and ionize the process gas to thereby generate plasma within the chamber, and wherein said first antenna segment surrounds said second antenna segment.