Fabrication of integrated circuits using positive photopatternable dielectrics containing high silicon content polysilsesquioxanes

Abstract

The method includes forming a first layer of a dielectric precursor composition on a substrate, the dielectric precursor composition including a silicon-containing polymer resin, a catalyst capable of catalyzing a condensation reaction of the silicon-containing polymer resin but deactivated in the presence of an acid, and a photoacid generator; irradiating a portion of the first layer of the dielectric precursor composition with radiation in a first imagewise manner to generate an acid in the irradiated portion; heating the exposed first layer to form a cured dielectric resin in the portion of the first layer that has not been irradiated with the radiation; after heating, removing the dielectric precursor composition in the portion irradiated with the radiation; and filling the portion from which the dielectric precursor has been removed with a metal. The dielectric precursor composition is characterized in that the cured resin after curing contains more than 42% by weight of silicon.

Description

[Technical Field]

[0001] The present invention relates to methods for forming metal patterns in dielectric materials, and more particularly to methods for forming interconnects used in integrated circuits. [Background technology]

[0002] An integrated circuit includes a semiconductor substrate having one or more layers of dielectric material with conductive interconnects formed by metal via holes or metal trenches formed in the dielectric material. A typical process for forming such a structure includes forming a dielectric layer, applying a photoresist or photosensitive hard mask, imaging and developing the photoresist to expose portions (or regions) of the dielectric layer, etching the dielectric layer to form the via holes and / or trenches, and filling the via holes and / or trenches with metal.

[0003] For example, as shown in FIGS. 1(a)-1(c), a photoresist 11 is applied to a non-photosensitive dielectric material 12 on a substrate 13. The substrate 13 may comprise, for example, a metal, a semiconductor, a dielectric material, or a combination of two or more of these. For example, the substrate may have a metal top layer or may include metal features (e.g., lines) within the dielectric that can be connected to subsequent metal features by the methods shown. As shown in FIG. 1(a), the photoresist 11 is imagewise exposed to radiation of an activating wavelength and developed to remove portions of the photoresist 11 and expose portions of the non-photosensitive dielectric material 12. As shown in FIG. 1(b), the non-photosensitive dielectric material 12 is etched, for example, by reactive ion etching (RIE), to form voids 14 (e.g., via holes or trenches) down to the substrate 13. The photoresist is also removed by etching. As shown in FIG. 1(c), the voids 14 are filled with metal 15, forming part of an interconnect. As another example, FIGS. 2(a) to 2(f) show a dual damascene method. As shown in FIG. 2(a), a photoresist 11 is exposed to radiation of an activating wavelength and developed to remove a portion of the photoresist 11 and expose a portion of the non-photosensitive dielectric material 12. As shown in FIG. 2(b), the non-photosensitive dielectric material 12 is etched, for example, by reactive ion etching (RIE), to remove the photoresist 11 and form a void 14 for a via hole. As shown in FIG. 2(c), a second photoresist 11 is applied to the non-photosensitive dielectric material 12, and the void 14 is filled. As shown in FIG. 2(d), the photoresist 11 is imagewise exposed to radiation of an activating wavelength and developed to remove a portion of the photoresist 11 and expose a portion of the non-photosensitive dielectric material 12. As shown in Figure 2(e), the photoresist 11 and a portion of the non-photosensitive dielectric material 12 were removed by etching to form a void 14 having a first region 14v for a via hole and a second region 14t for a trench. The void was filled with metal 15 as shown in Figure 2(f).

[0004] Examples of photoresists include hydrocarbon-based photoresists (e.g., polyhydroxystyrene and polymethacrylate-based compositions containing a photosensitive compound or moiety) and silicon hard masks (see, e.g., US 2010 / 0261097, the entire contents of which are incorporated herein by reference). This process is time-consuming and costly.

[0005] To eliminate the need for photoresist and etching, various methods using photopatternable dielectrics have been proposed. See, for example, US8029971, WO2005 / 109490, and WO2011 / 057832, the entire contents of which are incorporated herein by reference. However, the methods of US8029971 and WO2011 / 057832 using silicon-based dielectrics are still cumbersome because they require a bake step before exposing and developing the dielectric material, and a hardening step after developing the dielectric layer. WO2005 / 109490 relates to a decomposable photosensitive trench layer material that can be at least partially removed through a top layer by heating, decomposition, and diffusion to form an air gap in the trench layer. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] US2010 / 0261097 [Patent Document 2] US8029971 [Patent Document 3] WO2005 / 109490 [Patent Document 4] WO2011 / 057832 Summary of the Invention [Problem to be solved by the invention]

[0007] However, there remains a need for more efficient methods of forming integrated circuits. [Means for solving the problem]

[0008] The present specification discloses a method for forming a metal interconnect in a dielectric material, the method comprising: forming on a substrate a first layer of a dielectric precursor composition comprising a silicon-containing polymer resin, a catalyst capable of catalyzing a condensation reaction of the silicon-containing polymer resin but deactivated in the presence of an acid to lose its ability to catalyze the condensation reaction, and a photoacid generator; exposing a first portion of the first layer of the dielectric precursor composition to radiation in a first imagewise direction to generate acid in the radiation-exposed first portion to form an exposed first layer; heating the exposed first layer to form a cured dielectric resin in a second portion of the first layer not exposed to the radiation; removing the dielectric precursor composition in the radiation-exposed first portion after the heating; and filling the first portion from which the dielectric precursor was removed with a metal.

[0009] Further disclosed is an article made by such a method, wherein the cured dielectric resin in the article may have a dielectric constant of less than 4, preferably less than 3. The cured dielectric resin layer, up to 1.5 μm thick, is resistant to cracking at temperatures up to 400° C.

[0010] The present specification further discloses a composition comprising a curable silicon-containing polymer resin, a catalyst capable of catalyzing a condensation reaction of the silicon-containing polymer resin, a photoacid generator, and an organic solvent, which upon curing, the silicon-containing polymer resin comprises greater than 42 wt. % silicon, preferably at least 42.5 wt. % silicon, more preferably at least 43 wt. % silicon, based on the total weight of the cured resin. [Brief explanation of the drawings]

[0011] Reference is now made to the drawings, which illustrate exemplary embodiments and in which like elements are numbered the same. [Figure 1] 1(a)-1(c) show an example of a prior art technique for forming metal features in a dielectric using photoresist. [Figure 2]2(a)-2(f) show an example of a conventional dual damascene process that uses photoresist to form metal features in a dielectric. [Figure 3] 3(a)-3(c) illustrate an example method for forming metal interconnects using the positive photopatternable dielectrics disclosed herein. [Figure 4] 4(a)-4(e) illustrate an example of a dual damascene method for forming metal interconnects using the positive photopatternable dielectrics disclosed herein. [Figure 5] 5(a)-5(f) illustrate an example method for forming metal interconnects using the positive photopatternable dielectrics disclosed herein. DETAILED DESCRIPTION OF THE INVENTION

[0012] The method includes forming a layer of a photopatternable dielectric precursor composition on a substrate, exposing the layer to radiation at an activating wavelength, heating to cure portions of the layer not exposed to the radiation, removing portions of the layer that were exposed to form void areas, and filling the void areas with a metal. This method eliminates the need for RIE, the step of removing photoresist, and the associated equipment and materials. The substrate may comprise a metal, a semiconductor, a dielectric material, or a combination of two or more thereof. The substrate may include a metal film or metal features in its top dielectric material to contact the additional metal incorporated in the method. For example, the substrate may comprise a semiconductor material such as Si, SiGe, SiGeC, SiC, GaAs, InAs, InP, or other III / V or II / VI compound semiconductors. The substrate may include, for example, a process wafer, such as a silicon wafer or a wafer produced at various steps of a semiconductor manufacturing process, such as an integrated semiconductor wafer. The substrate may include multiple layers or may be a single layer. The substrate may include, for example, a layered substrate, such as Si / SiGe, Si / SiC, silicon-on-insulator (SOI), silicon germanium-on-insulator (SGOI), or the like. Substrates comprising a combination comprising at least one of the above may be used.

[0013] The silicon dielectric precursor composition comprises a silicon-containing resin, a catalyst capable of catalyzing the condensation reaction of the silicon-containing resin but deactivated in the presence of acid, and a photoacid generator. Thus, when a coated area of ​​the silicon dielectric precursor composition is exposed to radiation of an activating wavelength, acid is generated and the catalyst is deactivated. Subsequently, curing occurs in one or more unexposed areas. Then, development with an appropriate developer removes one or more exposed areas. Therefore, the silicon dielectric precursor composition is a positive-acting composition.

[0014] The silicon-containing polymer resins can be prepared with one or more monomers having the following molecular structures or a combination of two or more of these:

[0015] [ka]

[0016] Preferably, it is (a), (b), or (a) and (b). Each occurrence of R is independently hydrogen or an alkyl group of 1 to 4 carbon atoms, preferably 1 to 3 carbon atoms, and more preferably 1 or 2 carbon atoms. Preferably, R is an alkyl group of 1 or 2 carbon atoms. Each occurrence of R is independently a monovalent organic group having 1 to 30 carbon atoms and, optionally, 1 to 5 heteroatoms selected from N, O, P, S, or a combination of two or more thereof. For example, R may be an alkyl group having 1 to 30 carbon atoms, an aryl group having 6 to 30 carbon atoms, an alkene group having 2 to 30 carbon atoms, or an alicyclic group having 3 to 30 carbon atoms. Each optionally includes -O-, -CO-, -OCO-, -COO-, or -OCOO- as part of its structure. R may be further substituted with one or more epoxy groups. Preferably, R1 is an alkyl group having 1 or 2 carbon atoms to provide the cured resin with a silicon content of greater than 42 wt. % based on the total weight of the cured resin.

[0017] Examples of preferred monomers include methyltrimethoxysilane, tetraethoxysilane, tetramethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, butyltrimethoxysilane, butyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, cyclopentyltrimethoxysilane, cyclopentyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, and cyclohexenyltriethoxysilane. trimethoxysilane, cyclohexenyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, benzyltrimethoxysilane, benzyltriethoxysilane, phenethyltrimethoxysilane, phenethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, methylethyldimethoxysilane, methylethyldiethoxysilane, dipropyldimethoxysilane, dibutyldimethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, trimethylmethoxysilane, dimethylethylmethoxysilane, dimethylphenylmethoxysilane, dimethylbenzylmethoxysilane, dimethylphenethylmethoxysilane, and the like, or a combination of two or more thereof.

[0018] Polymerization of the monomers can be carried out in an organic solvent. Exemplary organic solvents used for polymerization include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 2-methyl-1-propanol, acetone, acetonitrile, tetrahydrofuran, toluene, hexane, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl normal pentyl ketone, butylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, butylene glycol monoethyl ether, propylene glycol monoethyl ether, Examples of the organic solvent include ethylene glycol monoethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethyl pyruvate, butyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, tert-butyl acetate, tert-butyl propionate, propylene glycol mono-tert-butyl ether acetate, γ-butyrolactone, etc., or a combination of two or more thereof. The organic solvent may be propylene glycol monomethyl ether or propylene glycol methyl ether acetate.

[0019] Polymerization of the monomers can be carried out in the presence of one or more polymerization catalysts. The polymerization catalyst may be an acid catalyst. Exemplary acid catalysts include organic acids such as formic acid, acetic acid, oxalic acid, maleic acid, methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, and the like, or a combination of two or more thereof; or inorganic acids such as hydrofluoric acid, hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, perchloric acid, phosphoric acid, and the like, or a combination of two or more thereof. The acid catalyst may be acetic acid. The acid catalyst may be used in any suitable amount, such as 1 to 10% by weight of the reactor contents.

[0020] The polymerization is carried out at a temperature of 0°C to 110°C, 20°C to 110°C, 50°C to 110°C, or 80°C to 110°C.

[0021] Volatile alkanols formed during the condensation reaction can be removed by distillation as the reaction proceeds. The distillate may also contain the acid catalyst, water, and / or solvent. Nitrogen gas flowing through the reactor contributes to the distillation. Removal of the volatile alkanols can be carried out during or after the polymerization reaction.

[0022] The silicon-containing polymer resin thus formed can include polysiloxane, polysilsesquioxane, or a combination thereof.For example, the silicon-containing polymer resin can include both polysiloxane and polysilsesquioxane.The silicon-containing polymer resin can include a crosslinked network structure.The network structure can include a series of complex and diverse molecular structures of polysiloxane and polysilsesquioxane.For example, the network structure can include a variety of structures such as the following molecular structures:

[0023] [ka]

[0024] where R and R are as defined herein. However, the simplified structure above is not necessarily an accurate and complete description of the silicon-containing polymer resin. The monomers and polymerization process provide the most accurate description of the polymer.

[0025] The weight-average molecular weight Mw of the silicon-containing polymer resin before curing may be 1,000 to 50,000 g / mol, 1,500 to 30,000 g / mol, 2,000 to 20,000 g / mol, or 3,000 to 10,000 g / mol. The weight-average molecular weight can be determined by gel permeation chromatography (GPC) using polystyrene standards, as described in Williams and Ward, J. Polymer. Sci., Polymer. Letters, 6, 621 (1968), the entire contents of which are incorporated herein by reference.

[0026] Exemplary silicon-containing polymer resins include substituted siloxanes, substituted silsesquioxanes, substituted polysiloxanes, or substituted polysilsesquioxanes, such as substituted methyl siloxanes, substituted methyl silsesquioxanes, substituted phenyl siloxanes, substituted phenyl silsesquioxanes, substituted methyl phenyl siloxanes, substituted methyl phenyl siloxanes, substituted methyl phenyl silsesquioxanes, substituted dimethyl siloxanes, substituted diphenyl siloxanes, substituted methyl phenyl siloxanes, substituted polyphenyl silsesquioxanes, substituted polymethyl phenyl siloxanes, substituted polymethyl phenyl silsesquioxanes, substituted polymethyl siloxanes, substituted polymethyl silsesquioxanes, or combinations thereof.

[0027] The silicon-containing polymer resin is included in the dielectric precursor composition in an amount of, for example, 2 to 50 wt %, 4 to 40 wt %, or 10 to 30 wt %, based on the total weight of the dielectric precursor composition. Compositions having silicon-containing polymer resins in this weight range can produce film thicknesses of 100 nm to 4 μm at typical spin coating speeds, for example, 500 to 2000 rpm.

[0028] The catalyst in the silicon dielectric precursor composition can catalyze the condensation reaction of the silicon-containing resin, i.e., the silicon-containing resin can further crosslink through condensation. The catalyst is deactivated by an acid, such as the photoacid generated by a photoacid generator. As used herein, an acid-deactivated catalyst refers to a catalyst that is deactivated in the presence of an acid. Such a catalyst is called a curing catalyst.

[0029] The curing catalyst may include a quaternary ammonium and / or amine, such as methylamine, ethylamine, propylamine, butylamine, ethylenediamine, hexamethylenediamine, dimethylamine, diethylamine, ethylmethylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, cyclohexylamine, dicyclohexylamine, monoethanolamine, diethanolamine, dimethylmonoethanolamine, monomethyldiethanolamine, triethanolamine, hexamethylenetetramine, aniline, N,N-dimethylaniline, N,N-dimethylaminopyridine, pyrrole, piperazine, pyrrolidine, piperidine, benzyltriethylammonium chloride (BTEAC), tetramethylammonium chloride (TMAC), guanidine carbonate, tetramethylammonium hydroxide (TMAH), tetramethylammonium acetate (TMAA), tetrabutylammonium hydroxide (TBAH), tetrabutylammonium acetate (TBAA), cetyltrimethylammonium acetate (CTAA), tetramethylammonium nitrate (TMAN), or a combination of two or more thereof. Other exemplary catalysts include (2-hydroxyethyl)trimethylammonium chloride, (2-hydroxyethyl)trimethylammonium hydroxide, (2-hydroxyethyl)trimethylammonium acetate, (2-hydroxyethyl)trimethylammonium formate, (2-hydroxyethyl)trimethylammonium nitrate, (2-hydroxyethyl)trimethylammonium benzoate, tetramethylammonium formate, or a combination of two or more thereof.

[0030] The amount of the curing catalyst may be about 0.0005 wt% to about 0.2 wt%, or about 0.001 wt% to about 0.05 wt%, based on the total weight of the dielectric precursor composition. The amount of the catalyst may be about 0.045 wt% to about 4 wt%, or 0.01 wt% to about 0.5 wt%, based on the weight of the silicon-containing polymer resin. The photoacid generator is a compound that generates an organic acid upon irradiation with actinic rays or radiation, and known compounds can be used. The photosensitive wavelength of the photoacid generator may be, for example, 10 nm to 450 nm, or 300 nm to 450 nm. In other words, the photoacid generator may be a compound that generates an acid in response to actinic rays in the above wavelength range. The pKa of the acid generated by the photoacid generator may be 4.0 or less, or 3.0 or less.

[0031] Photoacid generators include onium salts, triazine compounds (halomethylated triazine compounds, more particularly, for example, trichloromethyl-s-triazine compounds), oxime sulfonate compounds, bissulfonyldiazomethane compounds, imidosulfonate compounds, diazodisulfone compounds, disulfone compounds, and nitrobenzyl sulfonate compounds (e.g., o-nitrobenzyl sulfonate compounds). Photoacid generators include sulfonium salts or iodonium salts, such as compounds of sulfonium cations with sulfonates or methides, or compounds of iodonium cations with sulfonates. Exemplary sulfonium cations include triphenylsulfonium and tris(4-tert-butoxyphenyl)sulfonium. Exemplary sulfonates include trifluoromethanesulfonate and nonafluorobutane-1-sulfonate. Exemplary methides include tris(trifluoromethyl)methide. Exemplary iodonium cations are iodonium cations with aryl groups, such as diphenyliodonium and bis(4-tert-butylphenyl)iodonium. Exemplary sulfonates include trifluoromethanesulfonate and nonafluorobutane-1-sulfonate.

[0032] Exemplary photoacid generators include, for example, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium trifluoroacetate, (4-methoxyphenyl)diphenylsulfonium trifluoromethanesulfonate, (4-methoxyphenyl)diphenylsulfonium trifluoroacetate, [4-(phenylthio)phenyl]diphenylsulfonium trifluoromethanesulfonate, [4-(phenylthio)phenyl]diphenylsulfonium trifluoroacetate, diphenyliodonium trifluoromethanesulfonate, trifluoro (p-tert-butoxyphenyl)phenyliodonium trifluoromethanesulfonate, diphenyliodonium p-toluenesulfonate, (p-tert-butoxyphenyl)phenyliodonium p-toluenesulfonate, triphenylsulfonium trifluoromethanesulfonate, (p-tert-butoxyphenyl)diphenylsulfonium trifluoromethanesulfonate, bis(p-tert-butoxyphenyl)phenylsulfonium trifluoromethanesulfonate, tris(p-tert-butoxyphenyl)trifluoromethanesulfonate (phenyl)sulfonium, triphenylsulfonium p-toluenesulfonate, (p-tert-butoxyphenyl)diphenylsulfonium p-toluenesulfonate, bis(p-tert-butoxyphenyl)phenylsulfonium p-toluenesulfonate, tris(p-tert-butoxyphenyl)sulfonium p-toluenesulfonate, triphenylsulfonium nonafluoro-1-butanesulfonate, triphenylsulfonium 1-butanesulfonate, trimethylsulfonium trifluoromethanesulfonate, p-toluenesulfonic acid Trimethylsulfonium, cyclohexylmethyl(2-oxocyclohexyl)sulfonium trifluoromethanesulfonate, cyclohexylmethyl(2-oxocyclohexyl)sulfonium p-toluenesulfonate, dimethylphenylsulfonium trifluoromethanesulfonate, dimethylphenylsulfonium p-toluenesulfonate, dicyclohexylphenylsulfonium trifluoromethanesulfonate, dicyclohexylphenylsulfonium p-toluenesulfonate, trinaphthylsulfonium trifluoromethanesulfonate,Cyclohexylmethyl(2-oxocyclohexyl)sulfonium trifluoromethanesulfonate, (2-norbornyl)methyl(2-oxocyclohexyl)sulfonium trifluoromethanesulfonate, Ethylenebis[methyl(2-oxocyclopentyl)sulfonium trifluoromethanesulfonate], 1,2'-naphthylcarbonylmethyltetrahydrothiophenium triflate, Diphenyliodonium trifluoroacetate, Diphenyliodonium trifluoromethanesulfonate, Trifluoromethanesulfonic acid (4- Onium salts such as (4-methoxyphenyl)phenyliodonium trifluoroacetate, (4-methoxyphenyl)phenyliodonium trifluoroacetate, [4-[(2-hydroxytetradecyl)oxy]phenyl]phenyliodonium trifluoromethanesulfonate, [4-[(2-hydroxytetradecyl)oxy]phenyl]phenyliodonium hexafluoroantimonate, [4-[(2-hydroxytetradecyl)oxy]phenyl]phenyliodonium p-toluenesulfonate, or combinations of two or more thereof, are also included.

[0033] Exemplary diazomethane compounds include bis(phenylsulfonyl)diazomethane, bis(p-toluenesulfonyl)diazomethane, bis(xylenesulfonyl)diazomethane, bis(cyclohexylsulfonyl)diazomethane, bis(cyclopentylsulfonyl)diazomethane, bis(n-butylsulfonyl)diazomethane, bis(isobutylsulfonyl)diazomethane, bis(isoamylsulfonyl)diazomethane, 1-tert-amylsulfonyl-1-(tert-butylsulfonyl)diazomethane, and the like, or combinations of two or more thereof.

[0034] Exemplary triazine compounds include 2-(3-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methylthiophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxy-β-styryl)-4,6-bis(trichloromethyl)-s-triazine, 2-piperonyl ... -[2-(furan-2-yl)vinyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(5-methylfuran-2-yl)vinyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(4-diethylamino-2-methylphenyl)vinyl]-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, and the like, or a combination of two or more thereof.

[0035] Exemplary imidosulfonate compounds include trifluoromethylsulfonyloxy-bicyclo-[2.2.1]-hept-5-ene-dicarboximide, succinimide trifluoromethylsulfonate, phthalimide trifluoromethylsulfonate, N-hydroxynaphthalimidomethylsulfonate, N-hydroxy-5-norbornene-2,3-dicarboximidepropylsulfonate, and the like, or combinations of two or more thereof.

[0036] A specific example of a photoacid generator is 2-(4-methoxyphenyl)([((4-methylphenyl)sulfonyl)oxy]imino)acetonitrile. The content of the photoacid generator may be about 0.05 wt% to 3 wt%, 0.1 wt% to 2 wt%, 0.1 wt% to 1 wt%, or 0.2 wt% based on the total solid content of the composition. The molar ratio of photoacid generator to catalyst in the composition may be, for example, 0.5:1 to 10:1, 0.5:1 to 5:1, or 0.5:1 to 1.5:1. The cured silicon-containing dielectric may have a high silicon content, for example, greater than 35 wt%, greater than 38 wt%, greater than 39 wt%, greater than 40 wt%, greater than 41 wt%, greater than 42 wt%, at least 42.5 wt%, or at least 43 wt%, 46 wt% or less, or 45 wt% or less, based on the total weight of the cured silicon-containing dielectric.

[0037] The step of forming a layer of a photopatternable dielectric precursor composition on a substrate includes applying a coating composition to the substrate, the coating composition including a silicon-containing polymer resin, a catalyst (i.e., an acid-deactivatable curing catalyst), a photoacid generator, and a coating solvent.

[0038] Exemplary paint solvents include non-hydrocarbon solvents such as ketones such as acetone, diethyl ketone, and methyl ethyl ketone, alcohols, esters, ethers, and amines. Examples of solvents include propylene glycol monomethyl ether (PGME), propylene glycol methyl ether acetate (PGMEA), propylene glycol monopropyl ether (PGPE), and ethyl lactate (EL).

[0039] The solvent is contained in the composition in an amount of 50 wt % to 98 wt %, 55 wt % to 95 wt %, or 65 wt % to 90 wt %, based on the total weight of the dielectric precursor composition. Suitable application methods include spin coating, spray coating, etc. The solvent is removed to form a solid layer of the photopatternable dielectric precursor composition. Additional optional components of the coating composition include film modifiers to control the diffusion of components in the film, surfactants, and the like, or combinations of two or more of these.

[0040] The membrane modifier may be a polymer, oligomer, or non-polymer compound. The Mw of the polymer or oligomer used as the membrane modifier may be less than 5,000 g / mol or less than 2,000 g / mol, for example, 200 to 5,000 g / mol, or 500 to 2,000 g / mol. The membrane modifier molecules must be small enough to fill the pores of the membrane. The membrane modifier may be a hydrocarbon, preferably a silicon-containing compound. Meanwhile, at least one hydroxy group is bonded to each membrane modifier molecule. The hydroxy group can participate in the condensation reaction of the resin membrane. Exemplary hydrocarbon membrane modifiers include polyols such as, for example, polyether diols, glycerin, 2-(hydroxymethyl)-1,3-propanediol, 1,3-dihydroxypropan-2-yl dihydrogen phosphate, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and / or the like.Examples of branched alkylene glycols include neopentyl glycol, 2,4-diethyl-1,5-pentanediol, 2,4-dibutyl-1,5-pentanediol, 3-methyl-1,5-pentanediol, 1-methylethylene glycol, 1-ethylethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 1,1,1-tris(hydroxymethyl)ethane, 2-hydroxymethyl-1,3-propanediol, 2-ethyl-2-(hydroxymethyl)-1,3-propanediol, 2-hydroxymethyl-2-propyl-1,3-propanediol, 2-hydroxymethyl-1,4-butanediol, 2-hydroxyethyl-2-methyl-1,4-butanediol, 2-hydroxymethyl-2-propyl-1,4-butanediol, 2-ethyl-2-hydroxyethyl-1,4-butanediol, 1,2,3 -Butanetriol, 1,2,4-butanetriol, 3-(hydroxymethyl)-3-methyl-1,4-pentanediol, 1,2,5-pentanetriol, 1,3,5-pentanetriol, 1,2,3-trihydroxyhexane, 1,2,6-trihydroxyhexane, 2,5-dimethyl-1,2,6-hexanetriol, tris(hydroxymethyl)nitromethane, 2-methyl-2-nitro-1,3-propanediol, 2-bromo-2-nitro Examples of suitable membrane modifiers include 1,3-propanediol, 1,2,4-cyclopentanetriol, 1,2,3-cyclopentanetriol, 1,3,5-cyclohexanetriol, 1,3,5-cyclohexanetrimethanol, butane-1,2,3,4-tetrol, 2,2-bis(hydroxymethyl)-1,3-propanediol, pentane-1,2,4,5-tetrol, and the like, or a combination of two or more thereof. The membrane modifier may be 1,1,1-tris(hydroxymethyl)ethane, pentaerythritol, or a combination of two or more thereof.Exemplary silicon-containing film modifiers include silanols such as diphenylsilanediol, diisobutylsilanediol, 1,4-bis(dimethylhydroxysilyl)benzene, 4-vinylphenylsilanediol, or a combination of two or more thereof. The film modifier may be 30 wt% or less, or 10 wt% or less, of the total weight of the resin. The concentration of the film modifier in the composition controls the diffusion length of the catalyst, photoacid generator, and quencher. Also mentioned is an embodiment in which multiple film modifiers are used in the composition.

[0041] Solvent removal can be accomplished as part of the coating (e.g., spin coating) process. If this process does not sufficiently remove the solvent, an additional step may be performed, such as baking (e.g., on a hotplate surface) at 40°C to 120°C, 50°C to 100°C, or 60°C to 80°C for 15 to 120 seconds or 30 to 60 seconds. This bake step should not be for a time or at a temperature sufficient to cure the silicon-containing polymer resin so that the dried film remains soluble in developer.

[0042] The exposure can include exposure to radiation of an activating wavelength. The exposure is imagewise exposure to generate a pattern in the photopatternable dielectric precursor. The exposure can be done through a mask or by direct laser address. The activating wavelength can be, for example, in the range of 10 nm to 400 nm, or can be a specific wavelength such as 365 nm, 248 nm, 193 nm, 13.5 nm, etc. Combinations comprising at least one of the above wavelengths can be used.

[0043] The exposure to light deactivates the catalyst. During the subsequent heat curing period, the silicon-containing resin precursor cures (e.g., crosslinks) only in the areas not exposed to the radiation. Curing is carried out at a temperature of 60°C to 120°C or 80°C to 110°C for 30 to 120 seconds.

[0044] The exposed and cured silicon-containing dielectric can be developed using an organic solvent (especially a polar organic solvent) or a basic aqueous solution. Examples of organic solvents include cyclohexanone, methyl acetate, butyl acetate, ethyl acetate, isopropyl acetate, amyl acetate, isoamyl acetate, ethyl methoxyacetate, ethyl ethoxyacetate, propylene glycol monomethyl ether (PGME), ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monopropyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monophenyl ether acetate, diethylene glycol monobutyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ... ether acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxyamyl acetate, 3-methoxyamyl acetate, 4-methoxyamyl acetate, 2-methyl-3-methoxyamyl acetate, 3-methyl-3-methoxyamyl acetate, 3-methyl-4-methoxyamyl acetate, 4-methyl-4-methoxyamyl acetate, propylene glycol diacetate, methyl formate, ethyl formate, butyl formate, propyl formate, ethyl lactate, butyl lactate, propyl lactate, ethyl carbonate, propyl carbonate, butyl carbonate , methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl 3-methoxypropionate, and the like, or a combination of two or more thereof.Examples of alkaline developers include aqueous solutions of organic or inorganic bases such as tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide, ethanolamine, propylamine, ethylenediamine, choline, potassium hydroxide, and sodium hydroxide. A specific example of the developer is an aqueous solution of tetramethylammonium hydroxide with a concentration ranging from 2.5 g / L to 25 g / L. Development is carried out under appropriately determined conditions, such as a temperature of 5°C to 50°C and a time of 10 to 600 seconds.

[0045] The thickness of the dielectric layer can be selected appropriately depending on the structure of the interconnect to be manufactured. For example, the thickness of the dielectric layer can be from 2 nm, 5 nm, or 10 nm to 10,000 nm, 5,000 nm, 1,000 nm, 900 nm, 800 nm, 700 nm, 600 nm, 500 nm, 400 nm, 300 nm, 200 nm, or 100 nm. The size of the via hole can be about 140 nm to 10 μm, or 40 to 1 μm in cross section or diameter. The width of the trench or line can be from 10 nm or 100 nm to 10 μm or 5 μm.

[0046] Metal filling methods include sputtering, physical vapor deposition, chemical vapor deposition, plasma CVD, atomic layer deposition, electroless plating, or a combination of two or more of these. Metals include tungsten, nickel, cobalt, copper, aluminum, gold, and silver.

[0047] After filling, the layer is planarized, for example, using chemical mechanical polishing to planarize the surface of the layer. As shown in Figures 3(a)-3(c), one example of the method disclosed herein involves forming a layer 20 of a photopatternable dielectric precursor composition 21 on a substrate 13. As shown in Figure 3(b), the photopatternable dielectric precursor is imagewise exposed to radiation at an activating wavelength, and layer 20 is heated to form a hardened dielectric 22. The portions of the layer exposed to the activating wavelength radiation (the "first portion") are removed, for example, using a developer, to form voids 14 between the areas of hardened dielectric 22 (the "second portion"). As shown in Figure 3(c), metal 15 is filled into the voids 14.

[0048] As shown in Figures 4(a)-4(e), one example of the method disclosed herein involves forming a layer 20 of a photopatternable dielectric precursor composition 21 on a substrate 13. As shown in Figure 4(b), the photopatternable dielectric precursor is imagewise exposed to radiation at an activating wavelength, and the layer 20 is heated to form a cured dielectric 22. The portions of the layer exposed to the radiation at the activating wavelength (the "first portion") are removed, for example, using a developer, to form voids 14v (e.g., via holes) between the areas of cured dielectric 22 (the "second portion"). As shown in Figure 4(c), additional photopatternable dielectric precursor composition 21 is applied to fill the voids and cover the cured dielectric 22. As shown in Figure 4(d), additional photopatternable dielectric precursor 21 is imagewise exposed to activating wavelength radiation and further heated to form hardened dielectric 22, and the regions of the layer exposed to activating wavelength radiation ("first regions") are removed, for example, using a developer, to form voids 14t (e.g., trenches). Voids 14v and 14t are in fluid communication with each other, forming a continuous void region. Metal 15 is filled into voids 14t and 14v, as shown in Figure 4(e).

[0049] As an alternative to this method, rather than removing the first portion of the first layer exposed to the activating wavelength of radiation to form voids 14v as shown in Figure 4(b), a second layer of photopatternable dielectric precursor composition 21 is formed in the exposed and cured (undeveloped) photopatternable dielectric precursor composition, the second layer is then exposed and cured, and both the exposed and uncured first and second layers are simultaneously developed to yield the structure shown in Figure 4(d).

[0050] As shown in Figures 5(a)-5(f), one example of the method disclosed herein involves forming a layer 20 of a photopatternable dielectric precursor composition 21 on a substrate 13. As shown in Figure 5(b), the photopatternable dielectric precursor is imagewise exposed to radiation at an activating wavelength, and the layer 20 is heated to form a cured dielectric 22. The portions of the layer exposed to the radiation at the activating wavelength (the "first portion") are removed, for example, using a developer, to form voids 14v (e.g., via holes) between the regions of cured dielectric 22 (the "second portion"). As shown in Figure 5(c), metal 15 is filled into the voids 14v. Optionally, after metallization, the top surface may be planarized before proceeding to the next step. As shown in Figure 5(d), additional photopatternable dielectric precursor composition 21 is applied to the metal 15 and covers the cured dielectric 22. As shown in Figure 5(e), additional photopatternable dielectric precursor is imagewise exposed to activating wavelength radiation and further heated to form hardened dielectric 22, and the portions of the layer exposed to activating wavelength radiation ("first regions") are removed, for example, using a developer, to form trenches 14t (e.g., trenches). As shown in Figure 5(e), at least a portion of trench 14t overlies at least a portion of metal 15. However, in other embodiments, such overlap is not present. As shown in Figure 5(f), metal 15 fills trench 14t.

[0051] The steps of applying, exposing, curing, developing and filling can be repeated for subsequent layers forming a multi-layer interconnect.

[0052] Planarization can be performed to ensure a level surface to begin building the next layer, particularly planarization using chemical mechanical polishing, which can be performed after a metallization step.

[0053] After curing, the dielectric is resistant to chemicals, and once cured, there is no or virtually no outgassing from the dielectric material.

[0054] The cured dielectric film may have a dielectric constant of less than 4 or less than 3.5, and greater than 2 or 2.5. The dielectric constant can be measured with an impedance analyzer (e.g., Keysight Model E4990A) in accordance with ASTM D150.

[0055] Articles containing metal features and cured dielectrics produced by the methods disclosed herein are resistant to cracking. For example, such articles do not crack when heated to 400°C. In particular, a 1.5 μm thick cured dielectric baked at 400°C for 30 minutes cooled with no visible or microscopic cracks.

[0056] A product may be an electronic device, such as a chip or integrated circuit, or a system containing such a device, such as a computer, a mobile phone, a transportation vehicle, an appliance, a manufacturing system, or a robotic device.

[0057] Example Example 1: Synthesis of silicon-containing polymer resins and preparation of photopatternable dielectrics A 500 mL round-bottom flask was charged with 60 g of methyltrimethoxysilane, 30 g of tetraethoxysilane, 250 g of 1-methoxy-2-propanol acetate, 42 g of water, and 9 g of acetic acid, mixed thoroughly, and distilled for 5 hours. The temperature of the contents of the flask was raised to the boiling point. The silicon-containing polymer resin was recovered from the flask.

[0058] Example 2: Preparation of photopatternable dielectric and process conditions for dielectric patterning. 6 g of the silicon-containing polymer resin obtained in Example 1, 0.5 g of 1-methoxy-2-propanol acetate, 1 g of 1-propoxy-2-propanol, 0.001 g of benzyltrimethylammonium chloride, and 0.01 g of 2-(4-methoxyphenyl)([((4-methylphenyl)sulfonyl)oxy]imino)acetonitrile were placed in a container and mixed until all components were dissolved. This solution was spin-coated onto a silicon wafer at a rotation speed of 1000 rpm. A film approximately 200 nm thick was formed on the surface of the wafer. No baking was required after spin-coating. This film was a 200 nm thick photopatternable dielectric. The coated wafer was imagewise exposed to radiation having a wavelength of 365 nm to generate acid in the exposed areas. The wafer was then baked at 120°C for 60 seconds. Following this bake, the wafer was immersed in a 2.38 wt% aqueous solution of tetramethylammonium hydroxide for 10 to 40 seconds to form the desired pattern in the dielectric film, which was then cured on a hot plate at 200°C for 120 seconds.

[0059] Example 3 The dielectric resin obtained in Example 1 was tested by spin-coating a 1.5 μm layer onto a substrate, baking at 400° C. for 30 minutes, and then cooling. Visual inspection with and without a microscope revealed no cracks.

[0060] Example 4 The silicon-containing polymer resin obtained in Example 1 was formed into a film, cured, and then the dielectric constant was measured using an E4990A impedance analyzer manufactured by Keysight Corp. The measured dielectric constant was 3.0.

[0061] Example 5 The cured silicone resin from the resin obtained in Example 1 was tested by inductively coupled plasma mass spectrometry (ICPMS) to determine its silicon content, which was about 43% by weight based on the total weight of the resin.

[0062] The present disclosure further includes the following aspects.

[0063] Aspect 1 A method for forming a metal interconnect in a dielectric material includes the steps of: forming on a substrate a first layer of a dielectric precursor composition comprising a silicon-containing polymer resin, a catalyst capable of catalyzing a condensation reaction of the silicon-containing polymer resin but which is deactivated in the presence of an acid and loses its ability to catalyze the condensation reaction, and a photoacid generator; exposing portions of the first layer of dielectric precursor composition to radiation in a first imagewise direction to generate acid in the portions exposed to the radiation; heating the exposed first layer to form a hardened dielectric resin in the portions of the first layer not exposed to the radiation; removing the dielectric precursor composition in the portions exposed to the radiation after heating; and filling with metal the portions from which the dielectric precursor was removed.

[0064] Aspect 2 The method of aspect 1 further includes applying a second layer of the dielectric precursor composition after filling with the metal a first portion of the first layer from which the dielectric precursor has been removed; exposing a first region of the second layer of dielectric precursor composition to radiation in a second imagewise direction to generate acid in the first region exposed to the radiation; heating the exposed second layer to form a hardened dielectric resin in a second region of the second layer not exposed to the radiation; removing the dielectric precursor composition in the first region of the second layer exposed to the radiation; and filling with metal the first region of the second layer from which the dielectric precursor has been removed.

[0065] Aspect 3 The method of aspect 1 further includes the steps of applying a second layer of the dielectric composition after removing the first portion of the dielectric precursor composition exposed to the radiation; imagewise exposing a first region of the second layer of the dielectric precursor composition to radiation so that the first region of the second layer overlaps the removed first region of the first layer, generating an acid in the first region of the second layer exposed to the radiation; heating the exposed second layer to form a hardened dielectric resin in the second region of the second layer not exposed to the radiation; removing the dielectric precursor composition in the first region of the second layer to form a continuous void region in the region where the first region of the first layer and the region of the second layer were removed; and filling the continuous void region with the metal.

[0066] Aspect 4 the method of claim 1, further comprising the steps of: applying a second layer of dielectric composition to the first layer after heating the exposed first layer to form a cured dielectric resin in a second portion of the first layer and before removing the first portion of the first layer exposed to radiation; imagewise exposing a first region of the second layer of dielectric precursor composition to radiation so that the first region of the second layer overlaps the first portion of the first layer and generating acid in the first region of the second layer exposed to radiation; heating the exposed second layer to form a cured dielectric resin in the second region of the second layer not exposed to radiation; removing the dielectric precursor composition in the exposed first portion of the first layer and in the first region of the layer to form a continuous void region; and filling the continuous void region with the metal.

[0067] Aspect 5 In the above described method, the cured dielectric resin comprises at least 38 wt. %, preferably at least 40 wt. %, more preferably at least 42 wt. % silicon based on the total weight of the cured dielectric resin.

[0068] Aspect 6 In the above described method, the silicon-containing polymer resin is

[0069] [ka] or a combination thereof, wherein R in each application is independently hydrogen or an alkyl group of 1 to 4 carbon atoms, preferably 1 to 3 carbon atoms, more preferably 1 or 2 carbon atoms, and preferably R is an alkyl group of 1 or 2 carbon atoms; and R1 in each application is independently an alkyl group, aryl group, alkene group, alicyclic group, epoxyalkyl group, or epoxycycloalkyl group, and preferably R1 is an alkyl group of 1 or 2 carbon atoms; and the monomers are polymerized in an organic solvent in the presence of a polymerization catalyst at a temperature of 80°C to 110°C, and volatile alkanol is removed during the polymerization to form the silicon-containing resin.

[0070] Aspect 7 In the above described method, the catalyst comprises a quaternary ammonium and / or amine, preferably benzyltriethylammonium chloride (BTEAC), tetramethylammonium chloride (TMAC), guanidine carbonate, tetramethylammonium hydroxide (TMAH).

[0071] Aspect 8 In the above-described method, the amount of the catalyst relative to the weight of the dielectric precursor composition is 0.0005 wt% to 0.2 wt%, preferably 0.001 wt% to 0.05 wt%, or the amount of the catalyst relative to the weight of the silicon-containing polymer resin is 0.005 wt% to 4 wt%, preferably 0.01 wt% to 0.5 wt%.

[0072] Aspect 9 In the above described method, the photoacid generator comprises an onium salt, preferably a sulfonium salt or an iodonium salt, more preferably a compound of a sulfonium cation with a sulfonate or methide, or a compound of an iodonium cation with a sulfonate.

[0073] Aspect 10 In the above described method, the molar ratio of the photoacid generator to the catalyst is 0.5:1 to 10:1.

[0074] Aspect 11 In the above described method, the radiation has a wavelength of 10 nm to 400 nm.

[0075] Aspect 12 In the above described method, the layer is exposed to the radiation imagewise through a mask or by laser address.

[0076] Aspect 13 In the above described methods, filling with metal comprises sputtering, evaporation, atomic layer deposition or a combination of two or more thereof.

[0077] Aspect 14 In the above described method, after filling with metal, excess metal is removed and planarized to form a flat surface.

[0078] Aspect 15 A product formed by the method of any one of Aspects 1 to 14.

[0079] Aspect 16 In the product according to aspect 15, the cured dielectric resin has a dielectric constant of less than 4, preferably less than 3.5.

[0080] Aspect 17 In the product according to the sixteenth aspect, the cured dielectric resin layer does not crack at temperatures up to 400°C.

[0081] Aspect 18 The composition comprises a curable silicon-containing polymer resin, a catalyst capable of catalyzing a condensation reaction of the silicon-containing polymer resin, a photoacid generator, and one or more organic solvents, such that upon curing, the resin comprises greater than 42 wt. % silicon, preferably at least 42.5 wt. % silicon, and more preferably at least 43 wt. % silicon, based on the total weight of the cured resin.

[0082] Aspect 19 In the composition described in Aspect 18 above, the curable silicon-containing polymer resin is a reaction product of monomers consisting of methyltrimethoxysilane, tetraethoxysilane, or a combination thereof.

[0083] All ranges disclosed herein include their endpoints, and each endpoint is independently combinable with the others. For example, the range "25 wt.% or less, particularly 5 wt.% to 20 wt.%" includes both the "5 wt.% to 25 wt.%" endpoint and all values ​​within that range. It is also possible to combine the upper and lower limits to form ranges. For example, the expressions "at least 1 wt.% or at least 2 wt.%" and "10 wt.% or less or 5 wt.% or less" can be combined to form ranges such as "1 wt.% to 10 wt.%, "1 wt.% to 5 wt.%, "2 wt.% to 10 wt.%, and "2 wt.% to 5 wt.%."

[0084] The present disclosure may alternately comprise, consist of, or consist essentially of any suitable elements disclosed herein. The present disclosure may additionally or alternatively be formulated to be free of, or substantially free of, any elements, materials, ingredients, adjuvants, or substances used in prior art compositions or that are not necessary to achieve the function and / or purpose of the present disclosure.

[0085] All cited patents, patent applications, and other documents are incorporated herein by reference in their entirety. However, if a term in this specification contradicts or conflicts with a term in a cited document, the term in this specification will take precedence over the term in the cited document.

[0086] Unless otherwise limited herein, all test standards are the latest standards in effect as of the filing date of this application, or, if priority is claimed, the test standards are the latest standards in effect as of the filing date of the earliest listed priority application.

Claims

1. forming on a substrate a first layer of a dielectric precursor composition comprising a silicon-containing polymer resin, a catalyst that catalyzes a condensation reaction of the silicon-containing polymer resin and is deactivated in the presence of an acid, the catalyst comprising a quaternary ammonium salt and / or an amine, and a photoacid generator; exposing a first portion of the first layer of dielectric precursor composition to radiation in a first imagewise direction to generate acid in the first portion, thereby deactivating the catalyst and rendering the first portion uncured; heating the first layer to form a hardened dielectric resin in a second portion of the first layer not exposed to the radiation; removing the uncured first portion of the dielectric precursor composition by development after the heating; and filling the first portion from which the dielectric precursor was removed with a metal. A method for forming a metal interconnect in a dielectric material.

2. filling with the metal a first portion of the first layer from which the dielectric precursor was removed, and then applying a second layer of the dielectric precursor composition; exposing a first area of ​​the second layer of the dielectric precursor composition to radiation in a second imagewise direction to generate acid in the radiation-exposed areas; heating the exposed second layer to form a hardened dielectric resin in second areas of the second layer not exposed to the radiation; removing the dielectric precursor composition in the first region of the second layer that was exposed to the radiation; and filling with a metal the first region of the second layer from which the dielectric precursor was removed. The method of claim 1.

3. removing the first portion of the first layer of dielectric precursor composition exposed to the radiation, and then applying a second layer of the dielectric precursor composition; imagewise exposing a first region of the second layer of the dielectric precursor composition to radiation so that the first region of the second layer overlaps the removed first portion of the first layer, and generating acid in the first region of the second layer exposed to the radiation; heating the exposed second layer to form a hardened dielectric resin in second areas of the second layer not exposed to the radiation; removing a dielectric precursor composition from a first region of the second layer to form a continuous void region in the region where a portion of the first layer and a portion of the second layer have been removed; and filling the continuous void area with the metal. The method of claim 1.

4. applying a second layer of the dielectric precursor composition to the first layer after heating the exposed first layer to form a hardened dielectric resin in a second portion of the first layer and before removing the first portion of the first layer exposed to the radiation; exposing a first region of the second layer of the dielectric precursor composition to radiation in an imagewise manner, the first region of the second layer overlapping a first portion of the first layer, and generating acid in the first region of the second layer exposed to the radiation; heating the exposed second layer to form a hardened dielectric resin in second areas of the second layer not exposed to the radiation; removing the exposed first portion of the first layer and the first region of the second layer from the dielectric precursor composition to form a continuous void region; and filling the continuous void area with the metal. The method of claim 1.

5. The dielectric resin obtained by curing the dielectric precursor composition contains at least 38 wt% silicon based on its total weight. The method according to any one of claims 1 to 4.

6. The silicon-containing polymer resin is 【Chemistry 1】 or a combination thereof, wherein R in each occurrence is independently hydrogen or an alkyl group of 1 to 4 carbon atoms, and R1 in each occurrence is independently an alkyl group, an aryl group, an alkene group, an alicyclic group, an epoxyalkyl group, or an epoxycycloalkyl group, and the monomers are polymerized in an organic solvent in the presence of a polymerization catalyst at a temperature of 80°C to 110°C, and volatile alkanol is removed during polymerization to form the silicon-containing polymer resin. The method according to any one of claims 1 to 4.

7. The catalysts include benzyltriethylammonium chloride (BTEAC), tetramethylammonium chloride (TMAC), guanidine carbonate, and tetramethylammonium hydroxide (TMAH). The method according to any one of claims 1 to 4.

8. The amount of the catalyst is 0.0005 wt % to 0.2 wt % based on the total weight of the dielectric precursor composition, or the amount of the catalyst is 0.005 wt % to 4 wt % based on the total weight of the silicon-containing polymer resin. The method according to any one of claims 1 to 4.

9. The photoacid generator contains an onium salt. The method according to any one of claims 1 to 4.

10. The method according to any one of claims 1 to 4, wherein the molar ratio of the photoacid generator to the catalyst is from 0.5:1 to 10:

1.

11. The method according to any one of claims 1 to 4, wherein the radiation has a wavelength of 10 nm to 400 nm.

12. A method described in any one of claims 1 to 4, wherein the first layer or the second layer of the dielectric precursor composition is exposed to the radiation in an imagewise manner through a mask or by laser addressing.

13. The method of any one of claims 1 to 4, wherein filling with metal comprises sputtering, evaporation, atomic layer deposition, or a combination of two or more thereof.

14. A method according to any one of claims 1 to 4, wherein after filling with said metal, excess metal is removed and planarised to form a flat surface.

15. A method according to any one of claims 1 to 4, wherein the cured dielectric resin has a dielectric constant of less than 4, preferably less than 3.

5.

16. 16. The method of claim 15, wherein the cured dielectric resin layer does not crack at temperatures up to 400°C.

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