A film deposition system includes a chamber, a stage disposed in the chamber configured to support a substrate, one or more gas inlet structures configured to supply one or more gases to an interior of the chamber, and one or more microwave-introducing windows that introduce microwave radiation to the chamber to excite the one or more source gases to produce a plasma proximate the stage. The gas inlet structures include one or more angled gas inlets that introduce a plasma-shaping gas flow to the chamber at an angle relative to a symmetry axis of the stage. The plasma-shaping gas flow interacts with the plasma in a way that facilitates axisymmetric deposition of material on a surface of the substrate with the plasma.