Plasma processing apparatus
An inductively-coupled-plasma (ICP) type plasma processing apparatus is provided. The plasma processing includes an antenna which is substantially straight in a plan view of the antenna. A plasma is generated for performing a plasma treatment to a substrate when a high frequency current is applied to the antenna to form an electric field in a vacuum container. The antenna includes two go-and-return conductors closely disposed to each other in an up-down direction, wherein the up-down direction is perpendicular to a surface of the substrate, and the high frequency current is applied to flow in opposite directions between the two go-and-return conductors. An interval is defined by a distance between the two go-and-return conductors in the up-down direction, varies in a longitudinal direction of the antenna.
1. A plasma processing apparatus, which is an inductively-coupled-plasma processing apparatus, comprising:
a first antenna, substantially straight in a plan view of the first antenna, wherein a plasma is generated for performing a plasma treatment to a substrate when a high frequency current is applied to the first antenna to form an electric field in a vacuum container, and the first antenna comprises:
two go-and-return conductors closely disposed to each other in an up-down direction, wherein the up-down direction is perpendicular to a surface of the substrate, and the high frequency current is applied to flow in opposite directions between the two go-and-return conductors, and
wherein an interval defined by a distance between the two go-and-return conductors in the up-down direction varies in a longitudinal direction of the first antenna.
2. The plasma processing apparatus as claimed in claim 1 , wherein the interval varies in the longitudinal direction of the first antenna to form a plurality of first intervals located at two terminals of the first antenna in the longitudinal direction and a second interval located at a central portion of the first antenna, the first intervals are larger than the second interval.
3. The plasma processing apparatus as claimed in claim 1 , further comprising:
a second antenna disposed in parallel to the first antenna, wherein a high frequency power is simultaneously supplied to each of the first antenna and the second antenna by using a common high frequency power source through a plurality of impedances respectively connected in series to the first antenna and the second antenna.
4. The plasma processing apparatus as claimed in claim 2 , further comprising: a second antenna disposed in parallel to the first antenna, wherein a high frequency power is simultaneously supplied to each of the first antenna and the second antenna by using a common high frequency power source through a plurality of impedances respectively connected in series to the first antenna and the second antenna.