Method of forming a conductive barrier layer having improved coverage within critical openings
AssigneeAdvanced Micro Devices, Inc.
InventorsMichael Friedemann, Volker Kahlert
Life of this patent
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Abstract
A conductive barrier layer may be formed within high aspect ratio openings by a two-step ionizing sputter deposition. The first step is performed at low pressure and low bias power to obtain good coverage of upper portions of the openings. In the second step, the bias power and the pressure are raised to improved directionality of the particles while at the same time increasing the scatter events so that an increased deposition rate at critical structure areas is obtained, thereby achieving a good coverage at lower sidewall areas.
Claims23
A method, comprising:
- depositing a first layer of conductive material onto a substrate having formed therein an opening in a sputter deposition atmosphere having a first state with a pressure of a first value and a bias power of a first value for accelerating target ions towards said substrate;
- establishing a second state for said sputter deposition atmosphere by increasing at least one of said bias power and said pressure to a second value;
- and
- depositing a second layer of conductive material in said sputter deposition atmosphere, said sputter deposition atmosphere being in said second state.
A method of controlling a deposition rate in an ionized sputter deposition process, the method comprising a sequence including:
- providing a substrate having formed therein at least one via opening with an upper portion and a lower portion;
- establishing a deposition atmosphere around said substrate with a specified pressure and a specified bias power for directing target ions towards said substrate;
- determining a thickness of a deposited layer at said upper portion and said lower portion of said via opening;
- and
- increasing at least one of said bias power and said pressure when an absolute amount of a difference of the thickness at said lower portion and said upper portion is less than a predefined threshold.
A method, comprising:
- forming, by sputter deposition, a conductive material layer over an interconnect opening formed on a substrate, wherein a bias power for enhancing a directionality of deposition particles and a pressure are selected to provide a greater thickness of said conductive material layer at an upper portion of said interconnect opening compared to a lower portion thereof;
- increasing said bias power and said pressure;
- and
- continuing the formation of said conductive material layer to predominantly deposit said conductive material layer at the lower portion.
Dependencies are inferred from the claim text.