Electrode assembly for plasma processing apparatus

A component of a plasma processing apparatus, comprising:

• a showerhead electrode including an attachment surface and an exposed surface adapted to be exposed to an interior of a plasma processing chamber;
• a backing plate including a first surface spaced from a second surface, the second surface contacting and being bonded to the attachment surface of the showerhead electrode, the backing plate including axially extending apertures extending between the first surface and the second surface, each of the apertures including a first portion opening in the first surface and a second portion opening in the second surface, the second portion being wider in a transverse direction than the first portion;
• and
• T-nuts having a T-shape, the second portions and the T-nuts having matching shapes which prevents rotation of the T-nuts located in the second portions of the apertures.

A showerhead electrode assembly for a plasma processing apparatus, comprising:

• a silicon showerhead electrode having gas injection openings and a plasma exposed surface;
• a graphite backing member secured to the silicon showerhead electrode, the backing member including a plurality of through apertures each having a first portion and a second portion wider than the first portion;
• a top plate including a plurality of through openings each of which is aligned with a respective aperture in the backing member;
• a plurality of T-nuts having a T-shape, each T-nut being mounted in a respective aperture of the backing member, each T-nut including a bearing surface bonded to a surface at least partially defining the second portion of the apertures;
• and
• a second fastener member engaged with each T-nut to secure the backing member to the top plate.

A component of a plasma processing apparatus, comprising:

• an electrode plate of an electrically and thermally conductive material, the electrode plate including a top surface and an exposed bottom surface adapted to be exposed to an interior of a plasma processing chamber;
• a backing plate of graphite material, the backing plate including a bottom surface and a top surface spaced from the bottom surface, the bottom surface of the backing plate contacting and bonded to the top surface of the electrode plate, the backing plate including axially extending apertures extending between the top surface and the bottom surface thereof, each of the apertures including a second portion opening in the bottom surface and a first portion opening in the top surface of the backing plate, the second portion being wider in a transverse direction than the first portion;
• and
• a plurality of fastener members each mounted in an aperture of the backing plate, each fastener member including a head configured to prevent rotation of the fastener member in the aperture and having a bearing surface bonded to a surface that at least partially defines the second portion of the aperture.