Showerhead with embedded nut

A gas distribution assembly comprising:

• a showerhead comprising:
• a body having an inner region and an outer region, the inner region having a back surface and a front surface defining a thickness of the inner region, the outer region having a back surface and a front surface defining a thickness of the outer region, the body bounded by an outer peripheral edge;
• a plurality of cavities within the outer region of the body, each of the cavities having a back surface with an opening extending to the back surface of the outer region, and a cover plate fused with the body, the cover plate having a back surface within the cavity and a front surface substantially coplanar with the front surface of the outer region of the body;
• and
• a nut positioned within and free to float within each of the cavities and configured to receive a bolt through the opening in the back surface of the cavity;
• a gas distribution funnel positioned above the inner region of the showerhead, the gas distribution funnel shaped so as to form a funnel-shaped space above the inner region;
• and
• a base ring overlapping the outer region of the showerhead, the base ring comprising a plurality of holes through the base ring, each hole aligned to an opening in the cavities, each hole containing the bolt configured to attach to the nut through the opening.