Adhesion improvement for low k dielectrics to conductive materials
Methods are provided for processing a substrate for depositing an adhesion layer between a conductive material and a dielectric layer. In one aspect, the invention provides a method for processing a substrate including positioning a substrate having a conductive material disposed thereon, introducing a reducing compound or a silicon based compound, exposing the conductive material to the reducing compound or the silicon based compound, and depositing a silicon carbide layer without breaking vacuum.
1. A method for processing a substrate, comprising:
positioning the substrate in a processing chamber, wherein the substrate comprises one or more patterned low k dielectric layers and a conductive material formed therein;
introducing a reducing compound comprising nitrogen and hydrogen into the processing chamber;
initiating a first plasma of the reducing compound in the processing chamber;
exposing the conductive material to the first plasma of the reducing compound;
terminating the first plasma and the reducing compound comprising nitrogen and hydrogen;
introducing an organosilicon precursor in the processing chamber;
initiating a second plasma of the organosilicon precursor in the processing chamber;
introducing the reducing compound with the organosilicon precursor; and
depositing a nitrogen doped silicon carbide dielectric material on the one or more patterned low k dielectric layers and conductive material without breaking vacuum.
2. The method of claim 1 , wherein the reducing compound comprises ammonia or a mixture of nitrogen gas and hydrogen gas.
3. The method of claim 1 , further comprising introducing an inert gas with the reducing compound.
4. The method of claim 1 , wherein the organosilicon precursor is selected from the group of trimethylsilane, 2,4,6,8-tetramethylcyclotetrasiloxane, octamethylcyclotetrasiloxane, dimethylphenylsilane, diphenylmethylsilane, and combinations thereof.
5. The method of claim 1 , further comprising introducing an inert gas, hydrogen gas, the reducing compound, or a combination thereof, with the organosilicon precursor.
6. The method of claim 1 , wherein the initiating a plasma comprises generating a plasma by a single-frequency RF power source or a dual-frequency RF power source.
7. The method of claim 1 , wherein the conductive material comprises copper, doped copper, or a copper alloy.
8. The method of claim 1 , wherein the one or more patterned low k dielectric layers comprise silicon carbide, doped silicon carbide, silicon oxycarbide, or combinations thereof.
9. A method for processing a substrate, comprising:
positioning the substrate in a processing chamber, wherein the substrate comprises one or more patterned low k dielectric layers and a conductive material formed therein;
introducing a reducing compound comprising nitrogen and hydrogen at a first flow rate into the processing chamber;
initiating a first plasma of the reducing compound in the processing chamber;
exposing the conductive material to the plasma of the reducing compound;
terminating the first plasma;
introducing an organosilicon precursor in the processing chamber;
introducing the reducing compound at a second flow rate greater than the first flow rate;
initiating a second plasma of the organosilicon precursor and the reducing compound in the processing chamber;
depositing a carbon doped silicon nitride dielectric material on the one or more patterned low k dielectric layers and conductive material;
terminating the second plasma;
introducing the organosilicon precursor in the processing chamber;
introducing the reducing compound at a third flow rate less than the second flow rate;
initiating a third plasma of the organosilicon precursor and the reducing compound in the processing chamber; and
depositing a nitrogen doped silicon carbide dielectric material on the one or more patterned low k dielectric layers and conductive material without breaking vacuum.