FI126817B

FI126817B - Siloxane polymers as well as processes and uses for their preparation

Info

Publication number: FI126817B
Application number: FI20125747A
Authority: FI
Inventors: Jyri Paulasaari; Tommi Pätäri; Juha Rantala
Original assignee: Pibond Oy
Priority date: 2012-06-29
Filing date: 2012-06-29
Publication date: 2017-06-15
Also published as: FI20125747A

Description

Siloxane polymers, methods of manufacturing the same and uses thereof

Technical Field

The present invention relates to siloxane monomers and polymers produced therefrom. In particular, the present invention concerns siloxane polymers of alkoxy-substituted silane monomers, which are useful in the electronic industry, for example as silicon-based antireflective coatings.

Background Art

Protected phenols are an important group of chemical units that are used in the materials for semiconductor industry. Usually, acid labile protecting groups, such as methoxymethoxy (MOM), 1-methoxyethoxy (MOE) and 1-ethoxyethoxy (EOE), are used to alter the hydrophilicity-hydrophophicity character of the material. In the presence of moisture, acidity generated by exposure of the material compounded with photo acid generator (PAG) to light, MOM, MOE and EOE -groups are cleaved to yield alcohol, aldehyde and parent phenolic group. The rate of the deprotection reaction is depended on the pKa and concentration of the acid, as well as temperature and amount of humidity. This property makes it possible to photopattern the material, since due to slight acidic nature of phenol group itself, only the areas with free phenolic groups can be washed away with basic solutions such as 2.38 % tetramethylammonium hydroxide (TMAH); acidic phenol and TMAH are known to form water soluble salt.

Siloxane resins are also an important class of materials used in semiconductor industry. They are easily cured by heat-induced silanol condensation reactions at 150 to 400 °C, to give film that are resistant to solvents. Siloxane films can be easily etched by using fluorine chemistry, such as CF4 and HCF3 plasma. The reaction between the fluorine ion and a silane is quite specific so it can be used to selectively remove only siloxane materials; organic films are generally etched only slowly with CF4 and CHF3 plasma.

Summary of Invention

Technical Problem

It is an aim of the present invention to provide substituted silane monomers which are useful in preparing silicon-based films.

It is another aim of the present invention to provide novel siloxane polymers capable of forming films having improved properties of adhesion.

Solution to Problem

In the connection with the present invention it has surprisingly been found that the adhesion of siloxane resin films can be improved by incorporating silane monomers which contain protected phenol or naphthol groups into the siloxane polymers. Such monomers can be incorporated for example during the process of siloxane hydrolysis polymerization.

There are only two known silane monomers synthesized previously in the literature that have an alkoxyalkoxy-protected phenol attached to silicon. Unrelated to semiconductor materials, DeShong P. et al.1 teaches how 2-methoxymethoxyphenyltriethoxysilane can be used in carbon-carbon bond forming coupling reactions with aryl halides in the presence of palladium catalysts, to give substituted diaryls. Mazhar, M. et al.2 on the other hand, 2-methoxymethoxyphenyldimethylmethoxysilane was synthesized in order to study pseudorotation on penta-coordinated silicon atom by 1H and 29Si NMR. No references to possible applications in semiconductor industry were made.

The silane monomers of the present invention are

represented by the following formulas: and

and wherein

Ri is selected from the group of acid labile protecting groups; R2 is selected from lower alkoxy groups; R3 is selected from lower alkyl and lower alkoxy groups, aryl groups, and vinyl and allyl groups; and R4 is selected from lower alkyl and lower alkoxy groups, aryl groups and vinyl and allyl groups.

The present monomers can be synthesized by a process including the steps of - protecting the OH-group of an ArOH group, wherein Ar stands for phenyl, hydroxybenzyl or naphthyl, with an acid labile protecting group, such as an alkoxyalkoxy group, for example a methoxymethoxy, 1-methoxyethoxy or 1-ethoxyethoxy group; - preparing the corresponding Grignard or organolithium reagent of the protected ArOH group; and - coupling of the Grignard or lithiate reagent with alkoxy- or chlorosilanes.

Using the monomers novel siloxane polymers, in particular homopolymers, can be produced by hydrolysis polymerization.

The siloxane polymers thus obtained can be used for producing films.

More specifically, the co-polymers according to the present invention are characterized by what is stated in claim 1.

The method according to the present invention are characterized by what is stated in the characterizing part of claim 4.

The uses according to the present invention are characterized by what is stated in claims 9 and 10. Advantageous Effects of Invention

The present alkoxysilanes bearing alkoxyalkoxy protected hydroxyarylene or hydroxybenzyl groups are found to be useful monomers for siloxane polymers with improved adhesion in applications in semiconductor industry.

Siloxane films prepared using the above mentioned alkoxyalkoxy phenyl or alkoxyalkoxy naphthyl silanes are useful for example in silicon antireflective coatings (Si-ARC).

Other features and advantages will become apparent from the following description.

Brief Description of Drawings

Next the invention will be examined more closely with the aid of a detailed description and with reference to the attached drawings, in which

Figure 1 shows the GC and MS spectra of 4-methoxymethoxyphenyltrimethoxysilane from Example lb;

Figure 2 shows the GC and MS spectra of 6-trimethoxysilyl-2-methoxymethoxynaphthalene from Example 3;

Figure 3 shows the 13C NMR of 4-(l-ethoxyethoxy)tolyl-3-triethoxysilane of Example 9; and Figure 4 shows the coupled 13C NMR of 4-(l-ethoxyethoxy)tolyl-3-triethoxysilane of Example 9.

Description of Embodiments

As discussed above, in the present context alkoxysilanes bearing acid labile protecting groups are provided as monomers for siloxane polymers with improved adhesion in applications in semiconductor industry.

The monomers can be characterized by the general formulas IVa to IVe:

In Formulas I to II and IVa to IVe

Rx is selected from the group of acid labile protecting groups, such as alkoxyalkoxy groups; R2 is selected from lower alkoxy groups; R3 is selected from lower alkyl and lower alkoxy groups, aryl groups, and vinyl and allyl groups; and R4 is selected from lower alkyl and lower alkoxy groups, aryl groups and vinyl and allyl groups.

In the present invention, the term "alkyl" generally stands for a branched or linear, optionally substituted saturated hydrocarbyl radical (alkyl group).

In the meaning of R3and R4, the "lower" alkyl group preferably contains 1 to 6 carbon atoms, which optionally bears 1 to 3 substituents selected from methyl and halogen. Particularly preferred examples of R3and R4, with respect to "lower alkyl", are represented by methyl, ethyl, n- or i-propyl, and n-, tert- or iso-butyl.

In the present invention, "alkoxy" stands for a group formed by an alkyl with adjacent oxygen atom.

In the meaning of substituents R2 to R4, "lower" alkoxy group preferably contains 1 to 6 carbon atoms, which optionally bears 1 to 3 substituents selected from methyl and halogen. Particularly preferred examples of R2 to R4, with respect to the meaning of "lower alkoxy", are represented by methoxy, ethoxy or isopropoxy group, which optionally is substituted.

In the meaning "alkoxyalkoxy" of substituent R4, "alkoxy" has the same meaning as above, in particular it stands for lower alkoxy groups, i.e. groups with 1 to 6 carbon atoms.

The "aryl" group as used herein, for example in the meanings of substituents R3 and R4,is preferably phenyl, which optionally bears 1 to 5 substituents selected from halogen, alkyl or alkenyl on the ring, or naphthyl, which optionally bear 1 to 11 substituents selected from halogen alkyl or alkenyl on the ring structure, the substituents being optionally fluorinated (including per-fluorinated or partially fluorinated). In the meaning of "aryl", phenyl is particularly preferred. Also other 2-ring and 3-ring aryl groups are contemplated.

Thus, in advantageous embodiments, silane monomers of Formulas I to III and Formulas IVa to IVc, are provided wherein

Ri is independently selected from CFI2OCFl3, l-(CH2CH2)OCH3 and l-(CH2CH2)OCH2CH3; R2 is independently selected from OMe and OEt; R3 is independently selected from OMe, OEt, Me, Et, Ph, Vi and Allyl; and R4 is independently selected from OMe, OEt, Me, Et, Ph, Vi and Allyl.

In the present context (above and below), the abbreviation "OMe" stands for methoxy, whereas "OEt" stands for ethoxy, "Me" stands for methyl, "Et" stands for ethyl, "Ph" stands for phenyl, "Vi" stands for vinyl and "Allyl" is an allyl group.

Preferred silane monomers are represented by those falling within formulas I to III given above, particularly preferred monomers are selected from the group of - p-(l-methoxyethoxy)phenyltrimethoxysilane, - 4-methoxymethoxyphenyltrimethoxysilane, - 6-trimethoxysilyl-2-methoxymethoxynaphthalene, - p-(l-ethoxyethoxy)phenyltrimethoxysilane, - 4-(l-ethoxyethoxy)tolyl-3-triethoxysilane, - 3-(l-ethoxyethoxy)phenyltrimethoxysilane, and - 4-(l-ethoxyethoxy)tolyl-3-triethoxysilane.

It has been found that the present polymers with phenol groups have excellent adhesion on various substrates. This may be due to the reactive and polar nature of the OH-group. Without limiting the invention, it can be postulated that many metal oxides found on the surface of common metals can form covalent bonds with phenols (Ph-O-Metal). In addition, covalent bonds between phenolic polymer and other polymers can be formed via their unsaturated sites such as ethenyl and aldehyde groups which react to phenolic rings via Friedel-Crafts -type electrophilic aromatic reactions.

The synthesis of the monomers disclosed herein includes the protection the OH-group of a corresponding starting compound with a suitable protecting group, in particular an alkoxyalkoxy group, such as methoxymethoxy, 1-methoxyethoxy or 1-ethoxyethoxy groups, preparation of the corresponding Grignard or organolithium reagent, and coupling of the Grignard or lithiate reagent with suitable alkoxy- or chlorosilanes.

Using the monomers of formulas I to III or IVa to IVe, wherein the residues have the same meaning as above, siloxane polymers or copolymers can be derived by conventional hydrolysis and condensation polymerization. Poly- and copolymerization will be discussed in more detail below.

Homopolymers can be produced which comprise one and the same monomer; it is also possible to produce siloxane co-polymer which are derived from two or more of the monomers defined above.

Another group of siloxane copolymers are obtained by copolymerizing one or several monomers of formulas I to III or IVa to IVe, wherein the residues have the same meaning as above, with one or more silane monomers having the following formulas (Formulas Va to Vf):

Formulas Va to Vf wherein B is selected from bivalent bridging groups, in particular from Cx to C10 alkylenes and C6 to C18 arylenes, such as methylene, ethylene, propylene or phenylene links; X is selected from Cx to C6 alkoxy, carbonyl-lower alkoxy and halo groups, such as OMe, OEt, OCOMe, Cl and Br groups; and Y is selected from FI, Ci to C6 alkyl (e.g. Methyl, Ethyl, propyl), Vinyl, Allyl, aryl groups with one or several rings, such as Phenyl, Styryl, Naphthyl, Phenanthrenyl, Anthracenyl, functionalized alky groups, such as Glycidyloxypropyl, Acryloxypropyl, Methacryloxypropyl, 3-Mercaptopropyl, and 3-Chloropropyl groups.

Siloxane copolymers are provided which contain one or more silane monomers having Formula IVa to IVc, in particular Formula I to III, and at least one monomer having Formula Va to Vf. The molar ratio between the monomers extends from 1:1000 to 1000:1.

It is preferred that the mole percentage of the present monomers lies in the range from 0.1 to 99 mol-%, in particular 0.1 to 50 mol-%, preferably 0.1 to 25 mol-%.

Already at a mole percent of 0.1 to 10 %, present monomers are capable of conferring properties of improved adhesion on the siloxane polymers.

In the polymerization or copolymerization, conventional hydrolysis and condensation polymerization techniques are employable.

Hydrolysis is achieved either neat or in a suitable solvent by using a dilute acid solution. Typically, the strength of the acid solution ranges from 0.00001 M to 1 M, in particular from about 0.0001 to 0.5 M.

The acid for the hydrolysis can be selected from mineral and organic acids, such as from hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, phosphoric acid, sulfuric acid, perchloric acid, formic acid, acetic acid, trichloroacetic acid, trifluoroacetic acid, maleic acid, succinic acid, trifluoromethane sulfonic acid, methanesulfonic acid, phenylsulfonic acid, and p-toluenesulfonic acid.

The polymerization or copolymerization can also be carried out in the presence of a solvent. Such solvents can be selected from the group of propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, n-methyl-2-pyrrolidone, anisole, benzyl alcohol, toluene, ethylbenzene, xylene, mesitylene, dimethylacetamide, dimethylformamide, l,3-dimethyl-3,4,5,6-tetrahydro-2(lH)-pyrimidinone, hexamethylphosphoramide, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, methyl lactate, ethyl lactate, propyl lactate, ethyl acetate, propyl acetate, butyl acetate, cyclopentanone, cyclohexanone, dimethylsulfoxide, methyl isobutyl ketone, methyl ethyl ketone, methyl propyl ketone, 2-heptanone, gamma-butyrolactone, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, ethyl pyruvate, ethyl cellosolve acetate, tetrahydrofurfuryl alcohol, tetrahydrofuran, 2-methyl tetrahydrofuran, 2-(methoxymethyl)-tetrahydrofuran, acetone, methanol, ethanol, isopropanol, n-butanol, sec-butanol, iso-butanol, t-butanol and any mixtures thereof.

The polymerization or copolymerization will yield a siloxane polymer or a siloxane copolymer having a molecular weight (Mw) in the range of range 500....5,000,000 g/mol, for example 500....100,000 g/mol.

The present siloxane polymers or copolymers find use in the electronic industry, for example the siloxane polymers can be used as silicon antireflective coating. Generally, the present polymers or copolymers can be used for making thin films having a thickness of about 0.1 to 1000 nm, in particular about 1 to 500 nm, for example about 1 to 150 nm. Film-forming can be carried out by spin coating.

The following non-limiting working examples illustrate the invention: EXAMPLES Example la

Synthesis of methoxymethyl chloride (MOMCI)

Tin(ll)chloride (0.1 g) and dimethoxymethane (84 g) were placed in a 500 mL rb flask with a stir bar, reflux condenser and joint for dropping funnel under argon. Acetyl chloride (88.5 g) was then slowly dripped in. When the reaction started to warm up the flask, cold water bath was used to keep internal temperature below 45°C. The reaction was allowed to proceed for 18 hours. GC was used to confirm the formation of MOMCI, along with methyl acetate.

Example lb.

Synthesis of 4-methoxymethoxyphenyltrimethoxysilane (4-MOMOPhTMOS)

To a 1000 mL rb flask were metered p-bromophenol (150 g), diisopropylethylamine (DIEP, 300 g), and tetrahydrofuran (THF, 100 mL). While maintaining internal temperature below 30°C by cold water bath, the MOMCI-solution from example la was slowly added under argon. The reaction was allowed to proceed for 18 hours at +23°C. The amine salt was removed by filtration under argon. THF, methyl acetate and other volatiles were then removed using rotary evaporator (20 mbar / 50°C). The remaining material, p-MOMOPhBr, was dissolved in dry THF (300 g). Another rb flask was filled with dry THF (300g), magnesium turnings (42 g) and tetramethoxysilane (TMOS, 200 g). The solution was heated to reflux, and p-MOMOPhBr was slowly added in. When the exotherm started to reflux the flask, more TMOS (150 g) was added at once. The reaction was allowed to cool down in air while maintaining proper stirring. Heptane (600 g) was then added, and the precipitated magnesium salts were removed by filtration. Remaining liquid was dried in a rotary evaporator, followed by vacuum distillation twice. 4-Methoxymethoxyphenyltrimethoxysilane was obtained (157 g, bp. 105...120°C / <5 mbar, purity >99% by GC/MS).

Example 2a

Synthesis of 1-methoxyethyl chloride (MOECI)

Tin(ll)chloride (0.1 g) and 1,1-dimethoxyethane (99.5 g) were placed in a 500 mL rb flask with a stir bar, reflux condenser and joint for dropping funnel under argon. Acetyl chloride (88.5 g) was then slowly dripped in. When the reaction started to warm up the flask, cold water bath was used to keep internal temperature below 45°C. The reaction was allowed to proceed for 18 hours. GC was used to confirm the formation of MOECI, along with methyl acetate.

Example 2b

Synthesis of p-(l-methoxyethoxy)phenyltrimethoxysilane (4-MOEOPhTMOS)

To a 1000 mL rb flask were metered p-bromophenol (150 g), DIEP (300 g), and THF (100 mL). While maintaining internal temperature below 30°C by cold water bath, the MOECI-solution from example 2a was slowly added under argon. The reaction was allowed to proceed for 20 hours at +23°C. The amine salt was removed by filtration under argon. THF, methyl acetate and other volatiles were then removed using rotary evaporator (20 mbar / 50°C). The remaining material, p-MOEOPhBr, was dissolved in dry THF (300 g). Another rb flask was filled with dry THF (300g), magnesium turnings (42 g) and TMOS (200 g). The solution was heated to reflux, and p-MOEOPhBr was slowly added in. When the exotherm started to reflux the flask, more TMOS (150 g) was added at once. The reaction was allowed to cool down in air while maintaining proper stirring. Heptane (600 g) was then added, and the precipitated magnesium salts were removed by filtration. Remaining liquid was dried in a rotary evaporator, followed by vacuum distillation twice. 4-(l-Methoxyethoxy)phenyl-trimethoxysilane was obtained (140 g, bp. 115...125°C / <5 mbar, purity >99% by GC/MS).

Example 3

Synthesis of 6-trimethoxysilyl-2-methoxymethoxynaphthalene (6-TMOS-2-MOMONp)

To a 2000 mL rb flask were metered 6-bromo-2-naphthol (300 g), DIEN (231.7 g), and THF (100 mL). While maintaining internal temperature below 30°C by cold water bath, the MOMCI-solution (283.9 g, prepared analogously to example la), was slowly added under argon. The reaction was allowed to proceed for 18 hours at +23°C. The amine salt was removed by filtration under argon. THF, methyl acetate and other volatiles were then removed using rotary evaporator (20 mbar / 50°C). The remaining material, 2-MOMO-6BrNp, was dissolved in dry THF (500 g). Another rb flask was filled with dry THF (1000g), magnesium turnings (40 g) and TMOS (448 g). The solution was heated to reflux, and 2-MOMO-6BrNp was slowly added in. The reaction was allowed to cool down in air while maintaining proper stirring. Hexanes (400 g) was then added, and the precipitated magnesium salts were removed by filtration. Remaining liquid was dried in a rotary evaporator, followed by vacuum distillation twice. 6-Trimethoxysilyl-2-methoxymethoxynaphthalene was obtained (130 g, bp. 140°C / <1 mbar, purity >99% by GC/MS).

Example 4a

Synthesis of p-(l-ethoxyethoxy)bromobenzene (4-EOEOPhBr) p-Bromophenol (500 g) and vinyl ethyl ether (250 g) were weighted to a 1000 mL rb flask, equipped with a stir bar and a reflux condenser. Pyridine hydrochloride (0.2 g) was added. When the reaction started, the inner temperature was kept below 40°C by cooling the flask with cold water bath. The reaction was allowed to proceed at rt for 18 hours, after which toluene (150 g) was added, and the solution was washed once with dilute sodium bicarbonate-water solution, followed by evaporation of the organic phase in a rotary evaporator (5 mbar / bath 45°C). GC/MS was used to confirm that the product was formed, and had over 95% purity.

Example 4b

Synthesis of p-(l-ethoxyethoxy)phenyltrimethoxysilane (4-EOEOPhTMOS)

Magnesium turnings (80 g), dry THF (1200 g) and TMOS (400 g) were placed in a 4L rb flask under argon. The solution was heated to 65°C, and ~30 mL of the 4-EOEOPhBr from example 6 was added, along with 1,2-dibromoethane (1.5 mL). When the reaction started, rest of 4-EOEOPhBr was gradually metered in via a rubber septum by a syringe so that gentle reflux was maintained. The reaction was allowed to cool down in air under proper agitation. When the temperature dropped below 55°C, heptane (2.5 L) was added to precipitate magnesium salts. Solution was filtered and evaporated to dryness in a rotary evaporator. The product, p-(l-ethoxyethoxy)phenyltrimethoxysilane was distilled twice under vacuum (250 g, bp 90...110°C / <2 mbar, purity >97% by GC/MS).

Example 5 4-MOMOPhTMOS from Example lb (1 g) was taken, and diluted with methanol (3 mL). One drop of 37% hydrochloric acid (pKa ~ -6) was added, GC/MS was used to monitor the reaction. It showed, that within five hours, complete deprotection to 4-hydroxyphenyltrimethoxysilane had happened.

Example 6 4-MOMOPhTMOS from Example lb (1 g) was taken, and diluted with methanol (3 mL). One drop of 37% hydrochloric acid was added and the solution was heated to reflux. GC/MS was used to monitor the reaction. It showed, that within three hours in reflux, not only complete deprotection to 4-hydroxyphenyltrimethoxysilane had happened, but substantial amount of free phenol was also formed. This demonstrates that the Si-phenol silicon-carbon bond may be susceptible to cleavage in acidic environment at elevated temperatures.

Example 7 4-MOMOPhTMOS from Example lb (1 g) was taken, and diluted with methanol (3 mL). One drop of 50% trifluoroacetic acid (pKa ~ 0.3) was added, and GC/MS was used to monitor the reaction. It showed, that after 24 hours, only starting monomer was seen and no deprotection to 4-hydroxyphenyltrimethoxysilane had occurred. This indicates that the pKa of the acid used in the deprotection reaction has strong impact on the deprotection rate.

Example 8

Synthesis of 3-(l-ethoxyethoxy)phenyltrimethoxysilane (3-EOEOPhTMOS). 3-Bromophenol (155 g) and vinyl ethyl ether (100 g) were mixed in a 500 mL rb flask and pyridine hydrochloride (0.1 g) was added. The reaction was allowed to proceed for three days at rt. The volatiles were then evaporated, hexane (500 g) was added and the solution washed three times with DIW (100g). Hexane was removed by rotary evaporator and the product, 3-(l-ethoxyethoxy)bromo-benzene (212 g) was distilled at 70°C/<5mbar. Next, a 3L three neck rb flask was filled with magnesium turnings (30 g), THF (900 g) and tetramethoxysilane (350 g) under argon. The flask was heated to reflux, and 3-(l-ethoxyethoxy)bromobenzene was added in as 30 mL portions, keeping reflux in control. The flask was allowed to cool down, and most of the THF was removed by vacuum (~700 g). Heptane (500 g) was added to precipitated magnesium salts. The liquid phase was decanted, and evaporated at 50°C/5mbar. It was dissolved in heptane (300 g) and filtered. Distillation twice at 80...95°C /<1 mbar gave the product, 3-(l-ethoxyethoxy)phenyltrimethoxysilane (88 g, purity 97% by HPLC).

Example 9

Synthesis of 4-(l-ethoxyethoxy)tolyl-3-triethoxysilane (4-EOEOTol-3-TEOS)

Para-cresol (100 g), vinyl ethyl ether (90 g) and pyridine hydrochloride (0.5 g) were allowed to react for three days. When para-cresol had disappeared by GC, the solution was taken to rotary evaporator, and excess vinyl ethyl ether was removed. The remaining solution was washed with saturated NaHC03, followed by DIW. Distillation at 60°C/< lmbar gave 4-(l-ethoxyethoxy)toluene (162 g).

Sec-butyllithium (672 mL, 1.3M in cyclohexane/hexane) was slowly added to 4-(1-ethoxyethoxy)toluene (150 g). Lithiation was allowed to proceed for 20 hours at +23°C. The dark red solution obtained was slowly added to another solution, made of chlorotriethoxysilane (174g) and dry tetrahydrofuran (150 g) at -50 to -10°C. The reaction was allowed to warm up for two hours, after which it was washed with 100 mL saturated NaH2P04 solution and with 200 mL DIW twice. The product, 4-(l-ethoxyethoxy)tolyl-3-triethoxysilane was obtained by distillation under reduced pressure (121 g, bp. 80 to 105°C / <1 mbar, >96% pure by GC/MS). The structure was confirmed by 1H and 13C NMR.

Example 10

Polymer with 4-MOMOPhTMOS.

Tetraethoxysilane (70 g, 336 mmol), methyltriethoxysilane (9 g, 50 mmol), 4-methoxymethoxy-phenyltrimethoxysilane (13 g, 50 mmol) were diluted with acetone (200 g), and allowed to hydrolyzed with 0.01M HCI (32 g, 1.8 mol) at room temperature for 30 minutes, flowed by reflux for 5 hours. Propyleneglycol monomethyl ether acetate (PMEA, 300 g) was added, and the solution was rotary evaporated at 50C/10 mbar until all low volatile components were removed and the polymer was only in PGMEA. Mw/Mn = 2894/1722. The polymer was further diluted with PGMEA until 2 percent solution was obtained. After filtering the solution through a 0.04 pm Nylon filter, the solution was spin casted on a silicon wafer as a 45nm thick film, and cured at 250 °C for 5 mins. A 200 nm layer of a photoresist for ArF-laser (wavelength 193nm) was spin coated on top of the siloxane polymer layer and exposed at 250 J/m. A usable focus latitude range from -0.5 to +0.5 was achieved for 75nm lines.

Comparative Example 11

Polymer without 4-MOMOPhTMOS, replaced by PhTMOS

Tetraethoxysilane (70 g, 336 mmol), methyltriethoxysilane (9 g, 50 mmol), phenyltrimethoxysilane (10 g, 50 mmol) were diluted with acetone (200 g), and allowed to hydrolyzed with 0.01M HCI (32 g, 1.8 mol) at room temperature for 30 minutes, flowed by reflux for 5 hours. Propyleneglycol monomethyl ether acetate (PMEA, 300 g) was added, and the solution was rotary evaporated at 50C/10 mbar until all low volatile components were removed and the polymer was only in PGMEA. Mw/Mn = 2805/1750. The polymer was further diluted with PGMEA until 2 percent solution was obtained. After filtering the solution through a 0.04 pm Nylon filter, the solution was spin casted on a silicon wafer as a 45 nm thick film, and cured at 250 °C for 5 mins. A 200 nm layer of a photoresist for ArF-laser (wavelength 193nm) was spin coated on top of the siloxane polymer layer and exposed at 250 J/m. A usable focus latitude range from -0.2 to +0.2 was achieved for 75 nm lines. Pattern collapse due to adhesion failure was observed outside that range.

Industrial Applicability

The present products are suitable for use in the electronic and semiconductor industry, for example they can be used for making thin films.

Citation List 1 DeShong, P. et al., J. Org. Chem, (2004), 69(20), 6790-95. 1 Mazhar, M. et al., J. Chem. Soc. Pakistan (1990),12(3), 216-18.

Claims

Claim 1. A siloxane co-polymer is derived from two or more monomers selected from:

I and

and

wherein Rx is selected from the group consisting of acid labile protecting groups; R2 is selected from lower alkoxy groups; R3 is selected from lower alkyl and lower alkoxy groups, aryl groups, and vinyl and allyl groups; and R 4 is selected from lower alkyl and lower alkoxy groups, aryl groups and vinyl and allyl groups. Claim 2. The siloxane co-polymer according to claim 1, said co-polymer being derived from two or more monomers according to Formula I to III is selected from CH2OCH3, l- (CH2CH2) OCH3, and l- ( CH2CH2) OCH2CH3; R2 is selected from OMe and OEt; R3 is selected from OMe, OEt, Me, Et, Ph, Vi, and Allyl; and R 4 is selected from OMe, OEt, Me, Et, Ph, Vi, and Allyl. Claim 3. The siloxane co-polymer according to claim 1 or 2, said co-polymer being derived from two or more monomers selected from the group of -? - (l-methoxyethoxy) phenyltrimethoxysilane, - 4-methoxymethoxyphenyltrimethoxysilane, - 6-trimethoxysilyl. -2-methoxymethoxynaphthalene, - p- (l-ethoxyethoxy) phenyltrimethoxysilane, - 4- (l-ethoxyethoxy) tolyl-3-triethoxysilane, - 3- (l-ethoxyethoxy) phenyltrimethoxysilane, and - 4- (l-ethoxyethoxy) tolyl- 3-Triethoxysilane Claim 4. A method of producing a siloxane copolymer according to any one of claims 1 to 3, wherein the polymer or copolymer is obtained by hydrolysis of at least two monomers and subsequent condensation of the polymer. Claim 5. The method of claim 4, wherein the hydrolysis is achieved by either a dilute acid solution or a suitable solvent. Claim 6. Method of claim 4 or 5, resulting in strength of acid solution Ranges from 0.00001M to 1M. Claim 7. The method of any of claims 4 to 6, the acid is selected from hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, phosphoric acid, sulfuric acid, perchloric acid, formic acid, acetic acid, trichloroacetic acid, trifluoroacetic acid, maleic acid, succinic acid, trifluoromethane sulfonic acid, methanesulfonic acid, phenylsulfonic acid, p-toluenesulfonic acid. Claim 8. The method of any claims 4 to 7, wherein the solvent is selected from propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, n-methyl-2-pyrrolidone, anisole, benzyl alcohol, toluene, ethylbenzene, xylene, mesitylene, dimethylacetamide, dimethylformamide, 1,3-dimethyl-3,4,5,6-tetrahydro-2 (1H) -pyrimidinone, hexamethylphosphoramide, propylene glycol methyl ether, propylene glycol ethyl ether, propylene glycol propyl ether, methyl lactate, ethyl lactate, propyl lactate, ethyl acetate, propyl acetate, butyl acetate, cyclopentanone, cyclohexanone, dimethylsulfoxide, methyl isobutyl ketone, methyl ethyl ketone, methyl propyl ketone, 2-heptanone, gamma-butyrolactone, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, ethyl pyruvate, ethyl cellosolve acetate, tetrahydrofurfuryl alcohol, tetrahydrofuran, 2-methyl tetrahydrofuran, 2- (methoxymethyl) tetrahydrofuran, acetone, methanol, ethanol, isopropanol, n-butanol, sec-butanol, iso-butanol, t-butanol or any mixtures section. Claim 9. Use of a siloxane polymer according to any claims 1 to 3 in the electronic industry. Claim 10. Use of a siloxane polymer according to any of claims 1 to 3 as a silicon antireflective coating.

A siloxane copolymer derived from two or more monomers selected from the group consisting of compounds represented by the formulas:

and

i \ aava n and

wherein Rx is an acid labile protecting group, R2 is a lower alkoxy group, R3 is a lower alkyl or lower alkoxy group, an aryl group or a vinyl or allyl group, and R4 is a lower alkyl or lower alkyl group, an aryl group or a vinyl or allyl group.

Siloxane copolymer according to Claim 1, characterized in that the copolymer is derived from two or more monomers of the formula I-III, wherein R 1 is CH 2 OCH 3, 1- (CH 2 CH 2) OCH 3 or 1- (CH 2 CH 2) OCH 2 CH 3, R 2 is OMe or OEt, R 3 is OMe, OEt, Me, Et, Ph, Vi or allyl and R 4 is OMe, OEt, Me, Et, Ph, Vi or allyl.

Siloxane copolymer according to claim 1 or 2, characterized in that the copolymer is derived from two or more monomers selected from the group consisting of - p- (1-methoxyethoxy) phenyltrimethoxysilane, - 4-methoxymethoxyphenyltrimethoxysilane, - 6-trimethoxysilyl- -methoxymethoxynaphthalene, - p- (1-ethoxyethoxy) phenyltrimethoxysilane, - 4- (1-ethoxyethoxy) tolyl-3-triethoxysilane, - 3- (1-ethoxyethoxy) phenyltrimethoxysilane and - 4- (1-ethoxyethoxy) tolyl-3-triethoxysilane .

A process for preparing a siloxane copolymer according to any one of claims 1 to 3, characterized in that the polymer or copolymer is obtained by hydrolysis of at least two monomers followed by condensation polymerization.

Process according to claim 4, characterized in that the hydrolysis is carried out in a pure or suitable solvent using a dilute acid solution.

Process according to Claim 4 or 5, characterized in that the strength of the acid solution is 0.00001M - 1M.

7. The method according to any of claims 4-6, characterized in that the acid is hydrochloric acid, hydrobromic acid, hydroiodic acid, nitric acid, phosphoric acid, sulfuric acid, perchloric acid, formic acid, acetic acid, trichloroacetic acid, trifluoroacetic acid, maleic acid, succinic acid, trifluoromethanesulfonic acid, methane sulfonic acid, phenyl sulfonic or p-toluene sulfonic acid .

Process according to one of Claims 4 to 7, characterized in that the solvent is propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, n-methyl-2-pyrrolidone, anisole, benzyl alcohol, toluene, ethylbenzene, xylene, mesitylene, dimethyl-3,4,5,6-tetrahydro-2 (lH) -pyrimidinone, hexamethylphosphoramide, propylene glycol methyl ether, propyleeniglykolietyylieetteri, propyleeniglykolipropyylieetteri, methyl lactate, ethyl lactate, propyylilaktaatti, ethyl acetate, propyl acetate, butyl acetate, cyclopentanone, cyclohexanone, dimethyl sulfoxide, methyl isobutyl ketone, methyl ethyl ketone , methylpropyl ketone, 2-heptanone, gamma-butyrolactone, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, ethyl pyruvate, ethyl cellosoleate acetate, tetrahydrofurfuryl alcohol, tetrahydrofuran, 2-methyltetrahydrofuran, methanol, ethanol, isopropanol, n-butanol, sec-butanol, iso-butanol, t-butanol or a mixture thereof.

Use of a siloxane polymer according to any one of claims 1 to 3 in the electronics industry.

Use of a siloxane polymer according to any one of claims 1 to 3 as a silicon-based anti-reflection coating.