Patent ID: 7981473

Claim:
An atomic layer deposition (ALD) process using starved reactions, said ALD process comprising: exposing a wafer to a starved dose of a first chemically reactive precursor, said starved dose being selected to yield less than one-half of a maximum saturated ALD growth rate, measured in film thickness per ALD process cycle, for said first chemically reactive precursor, wherein said first chemically reactive precursor is a soft saturating precursor characterized by an onset of a slow increase in ALD growth rate with further increases of precursor exposure dose and having a longer saturation time as compared to a second chemically reactive precursor to follow the first chemically reactive precursor, and the exposure to the starved dose of the first chemically reactive precursor determines a value of a starved saturation ALD growth rate, measured in film thickness per ALD process cycle, for a second chemically reactive precursor to follow the first chemically reactive precursor; and exposing the wafer to a dose of the second chemically reactive precursor, the dose of the second chemically reactive precursor selected for achieving starved saturation of the second chemically reactive precursor under variations in dose of the second chemically reactive precursor, said starved saturation characterized by an ALD growth rate, measured in film thickness per ALD process cycle, of the second chemically reactive precursor being less than half of a maximum saturated ALD growth rate, measured in film thickness per ALD process cycle, for the second precursor, wherein: said starved dose of said first chemically reactive precursor and the dose of the second chemically reactive precursor are selected to obtain a maximum starved ALD process film deposition rate as measured in film thickness per unit time for the first and second chemically reactive precursors, and said first and second chemically reactive precursors are delivered sequentially in time.