ADDITIVE FOR ALD DEPOSITION PROFILE TUNING IN GAP FEATURES

A method for performing atomic layer deposition (ALD) on a substrate is provided, including: exposing the substrate to a first reactant and an additive simultaneously, the first reactant and the additive being configured to adsorb on exposed surfaces of the substrate, a partial pressure of the additive being configured so that adsorption of the additive in a gap feature of the substrate decreases as depth increases in the gap feature; after exposing the substrate to the first reactant and the additive, exposing the substrate to a second reactant, the second reactant configured to react with the adsorbed first reactant to form a thin film product, the second reactant configured to react with the adsorbed additive to remove the adsorbed additive from the substrate surface.