Organometallic solution based high resolution patterning compositions
Organometallic solutions have been found to provide high resolution radiation based patterning using thin coatings. The patterning can involve irradiation of the coated surface with a selected pattern and developing the pattern with a developing agent to form the developed image. The patternable coatings may be susceptible to positive-tone patterning or negative-tone patterning based on the use of an organic developing agent or an aqueous acid or base developing agent. The radiation sensitive coatings can comprise a metal oxo/hydroxo network with organic ligands. A precursor solution can comprise an organic liquid and metal polynuclear oxo-hydroxo cations with organic ligands having metal carbon bonds and/or metal carboxylate bonds.
1. A method for forming a patterned film supported by a substrate, the method comprising:
irradiating a layer of material supported by the substrate by exposing the layer of material to patterned radiation to form an irradiated structure with a region of irradiated material and a region with un-irradiated material, wherein the layer of material has a thickness in a range from about 1 nm to about 200 nm, wherein the un-irradiated material comprises a metal oxo-hydroxo network with metal cations having organic ligands with metal carbon bonds and/or with metal carboxylate bonds, and wherein the irradiated material is at least partially condensed to increase metal oxide character; and
developing the irradiated structure to selectively remove irradiated material or un-irradiated material to form the patterned film supported by the substrate.
2. The method of claim 1 wherein the layer of material is free of peroxide ligands.
3. The method of claim 1 wherein the metal oxo-hydroxo network is stable against ligand cleavage to provide a controlled response to irradiation.
4. The method of claim 1 wherein the irradiated material comprises an enhanced metal oxo-hydroxo network, wherein the enhanced metal oxo-hydroxo network has a lower carbon to metal ratio than the metal oxo-hydroxo network.
5. The method of claim 1 wherein the irradiating causes a reaction in the exposed region of the layer of material, the reaction comprising breaking of at least some of the metal carbon bonds and/or metal carboxylate bonds.
6. The method of claim 5 wherein the breaking of at least some of the bonds results in differential dissolution rates between the irradiated material and the un-irradiated material such that the irradiated structure can be alternatively subjected to positive tone imaging or negative tone imaging.
7. The method of claim 1 wherein the metal oxo-hydroxo network comprises both M-O-H linkages and M-O-M linkages, wherein M represents the metal.
8. The method of claim 1 further comprising heating the irradiated structure at a temperature from about 45° C. to about 250° C. for 0.1 minutes to about 30 minutes to form an annealed irradiated structure and developing the annealed irradiated structure.
9. The method of claim 1 wherein the metal comprises tin, antimony, indium or a combination thereof and wherein the organic ligand forms a radiation sensitive metal carbon bond and wherein the ligand forming the metal carbon bond comprises an alkyl ligand, alkenyl ligand, aryl ligand, or a combination thereof, each ligand containing 1 to 16 carbon atoms and/or wherein the organic ligands form a radiation sensitive metal carboxylate bond and wherein the metal carboxylate bond is formed by an alkyl carboxylate ligand, alkenyl carboxylate ligand, aryl carboxylate ligand or a combination thereof, each ligand having 1 to 16 carbon atoms.
10. The method of claim 1 wherein the metal comprises tin, antimony, indium or a combination thereof, and a combination of different alkyl ligands are bound to the metal.
11. The method of claim 1 wherein the organic ligands comprise methyl, ethyl, propyl, butyl, t-butyl, phenyl, benzyl, vinyl, allyl, acetate, propanoate, butanoate, benzoate, or combinations thereof.
12. The method of claim 1 wherein the organic ligands with metal carbon bonds comprise branched alkyl ligands.
13. The method of claim 1 wherein the metal comprises tin.
14. The method of claim 1 wherein the layer of material comprises one or more compositions with tin and non-tin metals in a blend.
15. The method of claim 1 wherein, prior to irradiating, the material has a mole ratio between the organic ligands and the metal cations from about 0.5 to about 3.
16. The method of claim 1 wherein the layer of material has a thickness in a range from about 1 nm to about 50 nm.
17. The method of claim 1 wherein the substrate comprises a semiconductor wafer.
18. The method of claim 1 wherein the irradiating comprises EUV, UV, or e-beam radiation exposure.
19. The method of claim 1 wherein the irradiating comprises EUV radiation at a dose from about 1 mJ/cm 2 to about 150 mJ/cm 2 , wherein the EUV radiation has a wavelength of 13.5 nm.
20. The method of claim 1 wherein the developing is performed with a reactive gas and/or a plasma or a liquid solution to selectively remove the irradiated material or the un-irradiated material.
21. The method of claim 1 wherein the developing is performed with a dry etch.
22. The method of claim 21 wherein the dry etch comprises halogen-based plasmas.
23. The method of claim 1 wherein the developing is performed with an organic developer to selectively remove the un-irradiated material, and wherein the organic developer comprises an aromatic compound, an ester, an alcohol, a ketone, an ether, or a combination thereof, optionally with up to 10% additive.
24. The method of claim 1 wherein the developing is performed with an aqueous developer to selectively remove the irradiated material.
25. The method of claim 24 wherein the aqueous developer comprises a quaternary ammonium hydroxide, a hydrogen fluoride, or an oxalic acid composition, optionally with up to 10% additive.
26. The method of claim 1 wherein the patterned film comprises a metal oxide.
27. The method of claim 1 wherein the patterned film supported by the substrate comprises features with an average pitch of no more than about 60 nm, average widths of no more than about 30 nm, and/or average line-width roughness of no more than about 3.0 nm.
28. The method of claim 1 further comprising forming the layer of material from a precursor composition comprising hydrolysable ligands and the organic ligands.
29. The method of claim 28 further comprising hydrolysing the precursor composition in the presence of atmospheric moisture to form the metal oxo/hydroxo network.
30. The method of claim 1 wherein, prior to irradiating, the material has a mole ratio between the organic ligands and the metal cations from about 0.75 to about 3.
31. The method of claim 1 wherein, prior to irradiating, the material has a mole ratio between the organic ligands and the metal cations of about 1.
32. The method of claim 1 wherein the layer of material has a thickness in a range from about 2 nm to about 40 nm.
33. The method of claim 1 wherein the layer of material has a thickness in a range from about 3 nm to about 25 nm.
34. The method of claim 1 wherein the irradiating comprises EUV radiation at a dose from about 3 mJ/cm 2 to about 50 mJ/cm 2 , wherein the EUV radiation has a wavelength of 13.5 nm.
35. The method of claim 1 wherein the layer of material comprises a first metal consisting of Sn, Sb, In or a combination thereof and a second metal consisting of one or more metal other than Sn, Sb or In, wherein the one or more metal other than Sn, Sb or In comprises Ti, Zr, Hf, V, Co, Mo, W, Al, Ga, Si, Ge, P, As, Y, La, Ce, Lu or combinations thereof, and wherein the mole ratio of the second metal to the first metal is from about 0.1 to about 0.75.