Showerhead assembly with gas injection distribution devices

A substrate processing apparatus, comprising:

• a chamber body;
• a substrate support;
• and
• a showerhead assembly, wherein a processing volume is defined by the chamber body, the substrate support, and the showerhead assembly, and wherein the showerhead assembly comprises:
• a showerhead having a first gas manifold formed in the showerhead;
• a plurality of first gas conduits extending through the showerhead and fluidly coupling the first gas manifold to the processing volume;
• and
• a plurality of gas distribution devices each having an annular orifice that is in fluid communication with the first gas manifold, wherein the plurality of gas distribution devices are configured to be coupled to a single gas source.

A method of processing substrates, comprising:

• introducing a first gas into a processing volume of a processing chamber through a plurality of gas distribution devices each having an annular orifice fluidly coupled to a first gas manifold formed in a showerhead, wherein the first gas is delivered from the first gas manifold into the processing volume through a plurality of first gas conduits;
• introducing a second gas into the processing volume of the processing chamber through a second gas manifold formed in the showerhead, wherein the second gas is delivered from the second gas manifold into the processing volume through a plurality of second gas conduits, and wherein the first gas manifold is isolated from the second gas manifold;
• and
• cooling the showerhead assembly by flowing a heat exchanging fluid through a temperature control manifold disposed in the showerhead assembly, wherein the plurality of first and second gas conduits are disposed through the temperature control manifold.