Embodiments described herein provide a gas supply system for reducing purge time and increasing processing throughput, and an atomic layer deposition (ALD) chamber having the same. The gas supply system includes an inert gas line and a precursor supply line. The inert gas line is configured to be coupled to an inlet of the chamber separate from the precursor supply line. Therefore, the inert gas is supplied concurrently to the precursor supply line and the processing region of the chamber such that total purge time is reduced. The reduction of the total purge time due to the gas supply system increases purge efficiency and increases processing throughput. Furthermore, the gas supply system allows inert gas to be utilized as a dilution gas during flow of precursors.