Patent ID: 7604709

Claim:
A plasma processing apparatus comprising: (a) a vessel in which a reduced pressure atmosphere is maintained; (b) a processing table on which a workpiece placed in said vessel is to rest; (c) a dielectric window arranged to face the workpiece on said processing table; and (d) plural antenna elements, located behind the dielectric window, which introduce electromagnetic waves into said vessel in order to turn a given gas into a plasma, wherein: the plural antenna elements include at least two antenna elements which are disposed in a plane so as to be rotationally symmetrically arranged and spaced circumferentially from each other about an axis of symmetry, and so as to be electrically separated from each other in said plane, each of said at least two antenna elements has one end portion which is grounded and another end portion which is electrically connected to a high frequency power supply, each of said at least two antenna elements has a non-loop configuration, and an entire length of each of said at least two antenna elements is spaced from said axis of symmetry and subtends an acute angle having a vertex at said axis of symmetry.