Method to obtain SiC class of films of desired composition and film properties
Provided are methods and systems for providing silicon carbide class of films. The composition of the silicon carbide film can be controlled by the choice of the combination of precursors and the ratio of flow rates between the precursors. The silicon carbide films can be deposited on a substrate by flowing two different organo-silicon precursors to mix together in a reaction chamber. The organo-silicon precursors react with one or more radicals in a substantially low energy state to form the silicon carbide film. The one or more radicals can be formed in a remote plasma source.
1. A method of depositing a silicon carbide film, the method comprising:
providing a substrate;
flowing a first organo-silicon precursor onto the substrate;
flowing a second organo-silicon precursor onto the substrate, wherein the first organo-silicon precursor is different from the second organo-silicon precursor, and wherein the first organo-silicon precursor and the second organo-silicon precursor are flowed together onto the substrate; and
introducing radicals from a source gas generated from a plasma source, wherein all or substantially all the radicals are in a substantially low energy state to react with the first and the second organo-silicon precursors to deposit the silicon carbide film on the substrate under conditions that break one or both of silicon-hydrogen bonds and silicon-silicon bonds but preserve silicon-oxygen, silicon-nitrogen, and/or silicon-carbon bonds, the broken silicon-hydrogen bonds and broken silicon-silicon bonds capable of cross-linking, the reaction occurring in a reaction space adjacent to the substrate and remote from the plasma source, the source gas being selected from a group consisting of: hydrogen, ammonia, and amine.
2. The method of claim 1 , wherein the silicon carbide film is doped with nitrogen and/or oxygen.
3. The method of claim 2 , wherein the silicon carbide film is a nitrogen doped silicon carbide film, the first organo-silicon and the second organo-silicon precursor each having different ratios of silicon-carbon bonds to silicon-nitrogen bonds.
4. The method of claim 2 , wherein the silicon carbide film is an oxygen doped silicon carbide filch, the first organo-silicon precursor and the second organo-silicon precursor each having different ratios of silicon-carbon bonds to silicon-oxygen bonds.
5. The method of claim 2 , wherein the silicon carbide film is an oxygen and nitrogen doped silicon carbide film, the first organo-silicon precursor having one or more silicon-oxygen bonds and the second organo-silicon precursor having one or more silicon-nitrogen bonds.
6. The method of claim 1 , wherein introducing the radicals comprises applying a remote plasma to react with the first and the second organo-silicon precursors, the remote plasma including at least 90% of the radicals in the reaction space being in the ground state.
7. The method of claim 1 , wherein a ratio of the flow rates between the first organo-silicon precursor and the second organo-silicon precursor is between about 1:1 and about 2:1.
8. The method of claim 1 , wherein a ratio of the flow rates between the first organo-silicon precursor and the second organo-silicon precursor is greater than about 2:1.
9. The method of claim 1 , wherein each of the first organo-silicon precursor and the second organo-silicon precursor has one or more silicon-hydrogen bonds and/or silicon-silicon bonds.
10. The method of claim 1 , wherein the radicals are produced from a source gas of hydrogen.
11. The method of claim 1 , wherein the silicon carbide film has a varying concentration of oxygen and nitrogen between a lower surface and an upper surface of the film.
12. The method of claim 1 , wherein the substrate comprises exposed copper, the method further comprising forming a nitrogen doped silicon carbide film directly over the exposed copper.
13. The method of claim 1 , wherein one of the first or the second organo-silicon precursors are cyclic siloxanes.
14. The method of claim 1 , wherein one of the first or the second organo-silicon precursors are alkoxy silanes.
15. The method of claim 1 , wherein one of the first or the second organo-silicon precursors are alkyl silanes.