Titanium nitride films
AssigneeMicron Technology, Inc.
InventorsBrenda D Kraus, Eugene P. Marsh
Life of this patent
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Abstract
The use of atomic layer deposition (ALD) to form a conductive titanium nitride layer produces a reliable structure for use in a variety of electronic devices. The structure is formed by depositing titanium nitride by atomic layer deposition onto a substrate surface using a titanium-containing precursor chemical such as TDEAT, followed by a mixture of ammonia and carbon monoxide or carbon monoxide alone, and repeating to form a sequentially deposited TiN structure. Such a TiN layer may be used as a diffusion barrier underneath another conductor such as aluminum or copper, or as an electro-migration preventing layer on top of an aluminum conductor. ALD deposited TiN layers have low resistivity, smooth topology, high deposition rates, and excellent step coverage and electrical continuity.
Claims23
An electronic device comprising:
- a semiconductor substrate including at least one transistor and at least one metallic interconnection;
- a conductive layer disposed below the metallic interconnection and above the substrate including a titanium nitride layer having a step coverage minimum layer thickness value greater than 75% of an average titanium nitride thickness on a horizontal portion of the semiconductor substrate, and a resistivity of less than 800 μohm-cm;
- wherein the titanium nitride layer has a chemical formula of TiNX, and the titanium nitride layer has a composition that continuously varies from an X value of 0.5 at a lower portion of the titanium nitride layer to an X value of greater than 1.0 at an upper portion of the titanium nitride layer.
An electronic system comprising:
- a controller;
- an electronic device coupled to the controller, wherein the electronic device includes:
- a semiconductor substrate including at least one transistor and at least one metallic interconnection;
- and
- a conductive layer disposed below the metallic interconnection and above the substrate including a titanium nitride layer having a step coverage minimum layer thickness value greater than 75% of an average titanium nitride thickness on a horizontal portion of the semiconductor substrate, and a resistivity of less than 800 μohm-cm, wherein the titanium nitride layer has a chemical formula of TiNX and the titanium nitride layer has a composition that continuously varies from an X value of 0.5 at a lower portion of the titanium nitride layer to an X value of greater than 1.0 at an upper portion of the titanium nitride layer.
An electronic device comprising:
- a semiconductor substrate including at least one transistor and at least one metallic interconnection;
- a conductive layer disposed above and in contact with a top portion of the metallic interconnection, including a titanium nitride layer having a step coverage minimum layer thickness value greater than 75% of an average titanium nitride thickness on a horizontal portion of the semiconductor substrate;
- wherein the titanium nitride layer has a chemical formula of TiNX, with a composition that continuously varies from an X value of 1.0 at a lower portion of the titanium nitride layer directly contacting the conductive layer to an X value of greater than 1.5 at an upper portion of the titanium nitride layer.
An electronic device comprising:
- a semiconductor substrate including at least one transistor and at least one metallic interconnection layer;
- a first conductive layer disposed below and in direct contact with a first metallic interconnection layer and above the semiconductor substrate, and a second conductive layer disposed above and in contact with a top portion of the first metallic interconnection layer;
- the first and second conductive layers including a titanium nitride layer having a step coverage minimum layer thickness value greater than 75% of an average titanium nitride thickness on a horizontal portion of the semiconductor substrate, wherein the titanium nitride layer has a chemical formula of TiNX, with a composition that continuously varies from an X value of 1.0 at a lower portion of the titanium nitride layer directly contacting the conductive layer to an X value of greater than 1.5 at an upper portion of the titanium nitride layer;
- and
- a second metallic interconnection layer including conductive layers in direct contact with both a top and a bottom surface.
Dependencies are inferred from the claim text.