Reactors for vapor deposition of materials onto a microelectronic workpiece, systems that include such reactors, and methods for depositing materials onto microelectronic workpieces. In one embodiment, a reactor for vapor deposition of a material comprises a reaction chamber and a gas distributor. The reaction chamber can include an inlet and an outlet. The gas distributor is positioned in the reaction chamber. The gas distributor has a compartment coupled to the inlet to receive a gas flow and a distributor plate including a first surface facing the compartment, a second surface facing the reaction chamber, and a plurality of passageways. The passageways extend through the distributor plate from the first surface to the second surface. Additionally, at least one of the passageways has at least a partially occluded flow path through the plate. For example, the occluded passageway can be canted at an oblique angle relative to the first surface of the distributor plate so that gas flowing through the canted passageway changes direction as it passes through the distributor plate.