Exemplary semiconductor showerheads may include a first plate characterized by a first surface in which a plurality of first apertures are defined, and further characterized by a second surface opposite the first surface and from which extends a plurality of annular members. Each annular member of the plurality of annular members may extend from a separate first aperture of the plurality of first apertures. A channel may be defined by each first aperture and corresponding annular member. The showerheads may also include a second plate coupled with the first plate and characterized by a first surface facing the first plate and a second surface opposite the first surface. A plurality of second apertures may be defined through the second plate within an internal area of the second plate. Each annular member of the plurality of annular members may extend within a separate second aperture of the plurality of second apertures.