Patent ID: 8413604
Filing Date: 2013-04-09
Classification: H01J,H01L,H05H

Abstract:
1. In a processing chamber that uses an inductively coupled plasma source defining an axis of symmetry and which produces a plasma density having a given radial variation characteristic across a treatment surface of a treatment object therein using a given electrostatic shield, an apparatus comprising: an electrostatic shield arrangement including at least a sidewall arrangement having a shape that extends through a range of radii relative to said axis of symmetry to replace said given electrostatic shield to provide for producing a modified radial variation characteristic across said treatment surface which is different than said given radial variation characteristic and where said electrostatic shield arrangement includes at least a first, inner shield member and a second, outer shield member, said inner shield member defining a first aperture pattern and said outer shield member defining a second aperture pattern, and the outer shield member nests proximate to the inner shield member with the inner and outer shield members being supported for rotation relative to one another such that the first aperture pattern cooperates with the second aperture pattern in a way which provides a range in said modified radial variation characteristic across said treatment surface by defining an effective aperture pattern that is made up of a plurality of effective apertures in which each effective aperture extends through at least a portion of the range of radii relative to the axis of symmetry and each effective aperture includes a width that varies at least partially along the length of that effective aperture to produce the modified radial variation characteristic, and each of the inner shield member and the outer shield member are frustoconical in configuration, said inner shield member including an inner shield sidewall and said outer shield member including an outer shield sidewall such that the inner shield sidewall and the outer shield sidewall are adjacent to one another.