Reduction of plasma edge effect on plasma enhanced CVD processes

A processing chamber, comprising:

• a chamber body defining a processing cavity;
• a substrate support member disposed in the processing cavity;
• an annular member comprising an upper section having an electrode mounting surface and a lower section integrally formed with the upper section having an inner annular confinement wall and an outer annular confinement wall, wherein the inner confinement wall diverges from the vertical at an angle toward the outer confinement wall;
• and
• a gas distribution assembly having a showerhead coupled to the annular member, wherein the diameter of the showerhead is substantially the same as the diameter of the outer annular confinement wall.

A processing chamber, comprising:

• a chamber body defining a processing cavity;
• a substrate support member disposed in the processing cavity;
• a gas distribution assembly comprising an annular member having an upper mounting surface, an inner confinement wall, and an outer confinement wall, wherein the inner confinement wall diverges from the vertical at an angle toward the outer confinement wall;
• and
• an isolation ring coupled to the upper mounting surface so as to define an interface that is parallel to the radial axis of the gas distribution assembly.

An apparatus for distributing a process gas within a substrate processing chamber, comprising:

• a gas distribution assembly;
• an annular member coupled to the gas distribution assembly, the annular member having an upper mounting surface, an inner confinement wall, and an outer confinement wall, the inner confinement wall diverging from the vertical at an angle toward the outer confinement wall;
• and
• an isolator ring coupled to the upper mounting surface so as to define an interface that is parallel to a radial axis of the gas distribution assembly.

A processing chamber, comprising:

• a chamber body defining a processing cavity;
• a substrate support member disposed in the processing cavity;
• and
• a gas distribution assembly comprising an annular member having an upper mounting surface, an inner confinement wall, and an outer confinement wall, wherein the inner confinement wall diverges from the vertical at an angle toward the outer confinement wall;
• and
• an isolator ring coupled to the upper mounting surface so as to define an interface that is parallel to a radial axis of the gas distribution assembly.

An apparatus for distributing a process gas within a substrate processing chamber, comprising:

• a gas distribution assembly;
• an annular member coupled to the gas distribution assembly, the annular member having an upper mounting surface, an inner confinement wall, and an outer confinement wall, the inner confinement wall diverging from the vertical at an angle toward the outer confinement wall;
• and
• an isolator ring disposed above the annular member and interposed between the gas distribution assembly and the substrate processing chamber.