Patent ID: 6796268
Filing Date: 2004-09-28
Classification: H01J

Abstract:
A microwave plasma processing system comprising:a processing vessel; an antenna for introducing microwaves into said processing vessel, the antenna having a plurality of substantially ring-shaped and substantially concentric antenna waveguides, each of said antenna waveguides having a substantially rectangular radial cross-section and comprising a proximal end portion configured to allow flow of the microwaves in only one radial direction, a terminal end portion, and a wall having a plurality of slots formed at a predetermined interval; a microwave supply source for supplying said microwaves to said antenna; and a connecting waveguide for connecting said microwave supply source to said proximal end portion of each of said antenna waveguides, wherein at least one of the connecting waveguide and the proximal end portions of the antenna waveguides are configured to guide the microwaves supplied from the microwave supply source to the respective one of the antenna waveguides such that the microwaves in each of the antenna waveguides flow in the direction opposite to that of the neighboring antenna waveguide, and wherein a plasma is produced in said processing vessel by said microwaves introduced from said antenna.