Patent ID: 7404984

Claim:
A method of depositing thin films by atomic layer deposition, wherein at least first and second vapor-phase reactants are alternately fed to a reaction space including a reaction chamber from separate inflow channels, the reaction space defining a reaction space volume X, the method comprising a plurality of cycles in which each cycle forms a saturated monolayer and includes: in a first pulse, flowing the first vapor-phase reactant through a first inflow channel opening directly into the reaction chamber, the reaction chamber housing a substrate upon which a thin film is to be deposited; in the first pulse, flowing only an inactive gas through a second inflow channel while flowing the first vapor-phase reactant through the first inflow channel, the second inflow channel opening directly into the reaction chamber; in a second pulse, flowing the second vapor-phase reactant through the second inflow channel; in the second pulse, flowing only an inactive gas through the first inflow channel while the second vapor-phase reactant flows through the second inflow channel; and moving a volume of at least 2X of inactive gas through the reaction space in an interval between each two successive pulses of the first and second vapor-phase reactants such that reactant molecules adsorbed on the walls of the reaction space are removed, the reaction space defined by the reaction chamber, the first inflow channel and the second inflow channel.