Multi-component conductive structures for semiconductor devices
Described are methods for forming multi-component conductive structures for semiconductor devices. The multi-component conductive structures can include a common metal, present in different percentages between the two components of the conductive structures. As described example, multiple components can include multiple ruthenium materials having different percentages of ruthenium. In some applications, at least a portion of one of the ruthenium material components will be sacrificial, and removed in subsequent processing.
1. A method of forming a semiconductor device, comprising:
depositing a first conductive material over a substrate structure by a cyclic deposition process, the deposited first conductive material comprising at least 60% ruthenium;
depositing a second conductive material on the first conductive material through a different deposition process than the cyclic deposition process, the deposited second conductive material comprising 40% or less of ruthenium;
wherein the substrate structure comprises:
a recess formed in the substrate structure, the recess at least partially defining at least two pillars; and
wherein the first and second conductive materials extend into the recess between the two pillars;
wherein the second conductive material comprises at least one of carbon, nitrogen, oxygen, silicon oxide, and polysilicon;
wherein the first and second conductive materials are formed using a first ruthenium-containing precursor; and wherein the second conductive material is formed through introduction of an additional precursor gas with a second ruthenium precursor; and
wherein the additional precursor gas comprises CH4 or C2H6.
2. The method of claim 1 , wherein the second conductive material comprises carbon.
3. The method of claim 1 , wherein the first ruthenium-containing precursor and the second ruthenium-containing precursor are the same.
4. The method of claim 1 wherein the first ruthenium-containing precursor includes CHDR.
5. The method of claim 1 , wherein the second conductive material is deposited on the first conductive material through a CVD process, and wherein the CVD-deposited second conductive material comprises 40% or less of ruthenium.