Gas distribution systems for deposition processes and methods of using the same. A substrate support member holding a substrate is disposed in a processing chamber. A plurality of first and second gas nozzles is connected to a gas distribution ring disposed in the processing chamber. The first gas nozzles provide a first reactant gas and include at least first and second outlet apertures. The second gas nozzles provide a second reactant gas and include third outlet apertures. The first outlet aperture is larger than the second outlet aperture, such that the first gas nozzle with the first outlet aperture creates an increased gas flow adjacent to a determined portion of the substrate to increase deposition from the first reactant gas on the determined portion of the substrate.