Method for depositing a planarization layer using polymerization chemical vapor deposition
A method is provided for depositing a planarization layer over features on a substrate using sequential polymerization chemical vapor deposition. According to one embodiment, the method includes providing a substrate containing a plurality of features with gaps between the plurality of features, delivering precursor molecules by gas phase exposure to the substrate, adsorbing the precursor molecules on the substrate to at least substantially fill the gaps with a layer of the adsorbed precursor molecules, and reacting the precursor molecules to form a polymer layer that at least substantially fills the gaps.
1. A method for processing a substrate, the method comprising:
providing a substrate containing a plurality of features with gaps between the plurality of features;
delivering precursor molecules by gas phase exposure to the substrate;
adsorbing the precursor molecules on the substrate to at least substantially fill the gaps with a layer of the adsorbed precursor molecules; and
reacting the precursor molecules to form a polymer layer that at least substantially fills the gaps.
2. The method of claim 1 , wherein the polymer layer overfills the gaps.
3. The method of claim 1 , wherein the adsorbing and reacting have at least partial temporal overlap.
4. The method of claim 1 , wherein the adsorbing and reacting have no partial temporal overlap.
5. The method of claim 1 , wherein the plurality of features form first and second regions on the substrate, and wherein the plurality of features in the first region having wider gaps than the plurality of features than the second region.
6. The method of claim 5 , wherein the polymer layer overfills the gaps, the method further comprising planarizing the polymer layer.
7. The method of claim 1 , wherein the precursor molecules include an acrylate.
8. The method of claim 1 , wherein the precursor molecules include monomers, dimers or oligomers of organic compounds that are capable of polymerization.
9. The method of claim 1 , wherein the precursor molecules include a vinyl functional group (—C═C—) or a carbon-carbon triple bond (—C≡C—).
10. The method of claim 1 , wherein the precursor molecules include two or more different reactive molecules.
11. The method of claim 10 , wherein one precursor molecule contains a hydroxyl group (—OH) and another precursor molecule contains an amine group (—NH 2 ).
12. The method of claim 10 , wherein one precursor molecule contains a hydroxyl group (—OH) and another precursor molecule contains a carboxylic acid group (—COOH) or an acyl chloride (—COCl).
13. The method of claim 1 , wherein the reacting is performed by heat-treating the substrate in a gaseous environment.
14. The method of claim 1 , wherein the reacting is performed by exposing the substrate to electromagnetic (EM) radiation.
15. The method of claim 1 , wherein the reacting includes free radicals formed from initiator molecules.
16. The method of claim 15 , wherein the initiator molecules include a peroxide.
17. The method of claim 16 , wherein the peroxide is selected from the group consisting of hydrogen peroxide (H—O—O—H), R—O—O—H, R—O—O—R′, and R—CO—O—O—H, where R and R′ are hydrocarbon moieties.
18. The method of claim 1 , wherein the reacting includes exposing the layer of the adsorbed precursor molecules to cations and free radicals that are generated in a plasma.
19. The method of claim 1 , further comprising
generating a vertical temperature gradient across a thickness of the layer of the adsorbed precursor molecules from a top surface of the layer of the adsorbed precursor molecules to a bottom surface of the layer of the adsorbed precursor molecules.
20. The method of claim 1 , further comprising
delivering cross-linker molecules into the layer of the adsorbed precursor molecules, wherein the cross-linker molecules contain at least two reactive sites.