Photocurable composition

Abstract

A photocurable composition may include a polymerizable material, a hindered stabilizer, and a photoinitiator wherein the polymerizable material includes at least one polyfunctional aromatic vinyl monomer; and the hindered stabilizer is a hindered amine of formula (1) or a hindered phenol of formula (2) (1), or (2) wherein X is H, CH3 or Y-Z; y is CH2, O, S or N; z is an organic substituent; r1 is H, CH3, OH, OR5, CO-CH3 or C (= O) R5; r1, R2, R3, R4 and R5 are organic substituent groups.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to photocurable compositions, in particular to photocurable compositions for inkjet adaptive planarization suitable for forming a photocured layer. BACKGROUND

[0002] Inkjet adaptive planarization (IAP) is a process for planarizing a surface of a substrate (e.g., a wafer including electrical circuits) by jetting droplets of a photocurable composition on the surface of the substrate and directly contacting a planarizing deck with the added liquid to form a planar liquid layer. The planar liquid layer is typically solidified under UV light exposure and after removal of the deck a planar polymer surface is obtained which can be subjected to subsequent processing steps such as baking, etching and / or further deposition steps.

[0003] Subsequent baking of the formed photocured layer is typically performed at a temperature above its glass transition temperature and close to its melting point and requires high thermal stability and low shrinkage.

[0004] There is a need for improved IAP materials wherein the photocurable composition has a long shelf life and which can form a planar photocured layer with high thermal stability during subsequent processing. SUMMARY

[0005] In one embodiment, the photocurable composition can include a photocurable composition including a polymerizable material, a hindered stabilizer, and a photoinitiator, wherein the polymerizable material includes at least one multifunctional aromatic vinyl monomer; and the hindered stabilizer can be a hindered amine of formula (1) or a hindered phenol of formula (2)

[0006] (1), or (2), wherein X is H, CH3, or Y-Z; Y is CH2, O, S, or N; Z is an organic substituent; R1is H, CH3, OH, OR5, CO-CH3, or C(=0)R5; R2, R3, R4, R5are organic substituents.

[0007] In one aspect of the photocurable composition, the hindered stabilizer can have the structure of formula (1) wherein X is Y-Z, wherein Z includes at least one reactive C=C group.

[0008] In a certain aspect of the photocurable composition, the hindered stabilizer can be a hindered amine selected from the group of:

[0009] ; or ; or

[0010] ; or ; or ; or

[0011] ; or .

[0012] In another aspect, the hindered stabilizer can have a molecular weight of at least 600 g / mol.

[0013] In other aspects of the photocurable composition, the hindered stabilizer can be a hindered phenol selected from the group of:

[0014] ; or ; or

[0015] ; or .

[0016] In one embodiment of the photocurable composition, the amount of hindered stabilizer can be at least 0.5 wt% and no greater than 5 wt%.

[0017] In another embodiment, the at least one multifunctional aromatic vinyl monomer of the polymerizable material can comprise a divinyl biphenyl monomer (DVBPh), or a trivinyl biphenyl monomer (TVBPh), or a trivinyl phenyl monomer (TVPh), or a combination thereof.

[0018] In one aspect, the at least one multifunctional aromatic vinyl monomer can comprise at least one vinyl group and at least one acrylate group.

[0019] In a certain aspect, the multifunctional aromatic vinyl monomer of the polymerizable material can be selected from:

[0020] ; or ; or ; or ; or

[0021] ; or ; or ; or

[0022] ; or .

[0023] In one aspect of the photocurable composition, the amount of multifunctional vinyl monomer can be at least 80 wt%, based on the total weight of the polymerizable material. In another aspect, the amount of multifunctional vinyl monomer can be at least 95 wt%, based on the total weight of the polymerizable material.

[0024] In another embodiment of the photocurable composition, the amount of polymerizable material can be at least 90 wt%, based on the total weight of the photocurable composition.

[0025] In one aspect, the carbon content of the photocured photocurable composition can be at least 71%.

[0026] In another aspect, the viscosity of the photocurable composition can be no greater than 30 mPa-s.

[0027] In a certain aspect, the photocurable composition can be substantially free of solvent.

[0028] In one embodiment, a laminate can include a substrate and a photocured layer overlying the substrate, wherein the photocured layer is formed from the photocurable composition of the present disclosure.

[0029] In one aspect of the laminate, the initial degradation temperature T(X) of the photocured layer can be at least 330°C.

[0030] In another embodiment, a method of forming a photocured layer on a substrate can include: applying a layer of a photocurable composition on a substrate, wherein the photocurable composition can include a polymerizable material, a hindered stabilizer, and a photoinitiator, wherein the polymerizable material includes at least one multifunctional aromatic vinyl monomer; and the hindered stabilizer is a hindered amine of formula (1) or a hindered phenol of formula (2):

[0031] (1), or (2), wherein X is H, CH3, or Y-Z, wherein Y is CH2, O, or S or N, and Z is an organic substituent; R1is H, CH3, OH, OR5, or CO-CH3, or COR5; R2, R3, R4, R5are the same or different organic substituents; contacting the photocurable composition with a platen or a stamping template; irradiating the photocurable composition with light to form a photocured layer; and removing the platen or the stamping template from the photocured layer.

[0032] In one aspect of the method, the initial degradation temperature T(X) of the photocured layer can be at least 330°C.

[0033] In another embodiment, a method of manufacturing an article can include: forming a photocured layer on a substrate as described above, forming a pattern on the substrate; and processing the substrate on which the pattern has been formed in the forming; and manufacturing the article from the substrate processed in the processing. BRIEF DESCRIPTION OF DRAWINGS

[0034] The embodiments are illustrated by way of example and not limited to the figures.

[0035] Figure 1 The figures include a graph showing a TGA curve obtained via dynamic thermogravimetric analysis of a photocured material made from the photocurable composition according to Example 1 of the embodiments.

[0036] Figure 2 This includes a graph showing the TGA curves of a photocurable material made from the photocurable composition of Example 1 according to the embodiment, obtained by isothermal thermogravimetric analysis at 350°C.

[0037] Figure 3 This includes a graph showing the TGA curves of a photocurable material made from the photocurable composition of Example 2 according to the embodiment, obtained by dynamic thermogravimetric analysis.

[0038] Figure 4 This includes a graph showing the TGA curves of a photocurable material made from the photocurable composition of Example 2 according to the embodiment, obtained by isothermal thermogravimetric analysis at 400°C. Detailed Implementation

[0039] The following description is provided to aid in understanding the teachings disclosed herein, with an emphasis on the specific implementation and application of the teachings. This emphasis is provided to aid in the description of the teachings and should not be construed as a limitation on the scope or applicability of the teachings.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Materials, methods, and examples are illustrative only and are not intended to be limiting. Many details regarding specific materials and processing actions beyond the scope described herein are conventional and can be found in textbooks and other sources within the fields of imprinting and photolithography.

[0041] As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having,” or any other variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, article, or apparatus that includes the listed features is not necessarily limited to those features, but may include other features not expressly listed or inherent to such a process, method, article, or apparatus.

[0042] As used herein, and unless explicitly stated otherwise, “or” means inclusive or and not exclusive. For example, condition A or B is satisfied by any of the following: A is true (or exists) and B is false (or does not exist), A is false (or does not exist) and B is true (or exists), and both A and B are true (or exist).

[0043] Furthermore, the terms "a" or "an" are used to describe the elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. The description should be understood to include one or at least one, and the singular includes the plural, unless it is obvious that it means otherwise.

[0044] The present disclosure relates to a photocurable composition comprising a polymerizable material, a hindered stabilizer, and a photoinitiator, wherein the polymerizable material can comprise at least one multifunctional aromatic vinyl monomer, and the hindered stabilizer can be a hindered amine of formula (1) or a hindered phenol of formula (2):

[0045] (1), or (2),

[0046] wherein X is H, CH3, or Y-Z; Y is CH2, O, S, or N; Z is an organic substituent;

[0047] R1is H, CH3, OH, OR5, CO-CH3, or C(=0)R5; R2, R3, R4, R5are organic substituents, wherein each organic substituent can be a different, or the same, or at least partially the same substituent.

[0048] Without being bound by theory, a photocurable composition comprising a certain combination of an aromatic vinyl monomer and a hindered stabilizer having the structure of formula (1) or formula (2) can have the advantage of having a long shelf life and forming a photocured layer having high thermal stability and high etch resistance during an IAP process.

[0049] In one embodiment, the hindered stabilizer can be a hindered amine having the structure of formula (1), wherein X is Y-Z, wherein Z comprises at least one reactive C=C group.

[0050] In one specific embodiment, the molecular weight of the hindered stabilizer can be at least 230 g / mol, or at least 250 g / mol, or at least 300 g / mol, or at least 400 g / mol, or at least 440 g / mol, or at least 500 g / mol, or at least 550 g / mol, or at least 600 g / mol. In another aspect, the molecular weight of the hindered stabilizer can be no greater than 3000 g / mol, or no greater than 2500 g / mol, or no greater than 2000 g / mol, or no greater than 1000 g / mol, or no greater than 800 g / mol, or no greater than 500 g / mol.

[0051] Non-limiting examples of hindered amine stabilizers can be one or more stabilizers of structures (3) to (9):

[0052] (3); (4);

[0053] (5); (6); (7); (8); or (9); or (10).

[0054] In another embodiment, the hindered stabilizer can be a hindered phenol having the structure of Formula (2). Non-limiting examples of hindered phenolic stabilizers falling within the structure of Formula (2) can be the following structures (11) through (14).

[0055] (11); (12);

[0056] (13); or (14).

[0057] In a certain aspect, the hindered stabilizer can also be a combination of at least one hindered amine of Formula (1) and at least one hindered phenol of Formula (2).

[0058] In one embodiment, the amount of hindered stabilizer of the photocurable composition of the present disclosure can be at least 0.1 wt%, or at least 0.3 wt%, or at least 0.5 wt%, or at least 1 wt%, or at least 2 wt%, or at least 3 wt%, or at least 4 wt%, or at least 5 wt%, based on the total weight of the photocurable composition. In another embodiment, the amount of hindered stabilizer can be no greater than 10 wt%, or no greater than 8 wt%, or no greater than 5 wt%, or no greater than 3 wt%. In a certain aspect, the amount of hindered stabilizer can be at least 0.5 wt% and no greater than 5 wt%, or at least 1.0 wt% and no greater than 3 wt%, based on the total weight of the photocurable composition.

[0059] The polymerizable material of the photocurable composition of the present disclosure can comprise at least one multifunctional aromatic vinyl monomer. In one aspect, the multifunctional aromatic vinyl monomer can comprise at least one aromatic ring, and at least two vinyl groups. In another aspect, the at least one multifunctional aromatic vinyl monomer can comprise at least one aromatic ring, at least one vinyl group, and at least one acrylate group.

[0060] In a certain aspect, the at least one multifunctional aromatic vinyl monomer can comprise a divinyl biphenyl monomer (DVBPh), or a trivinyl biphenyl monomer (TVBPh), or a trivinyl phenyl monomer (TVPh), or a combination thereof.

[0061] Non-limiting examples of multifunctional aromatic vinyl monomers can be one or more of the following monomers:

[0062] ; or ; or ; or ; or or or

[0063] ; or or .

[0064] The amount of the multifunctional aromatic vinyl monomer can be at least 70 weight percent, such as at least 75 weight percent, at least 80 weight percent, at least 85 weight percent, at least 90 weight percent, or at least 95 weight percent, based on the total weight of the polymerizable material. In another aspect, all of the polymerizable material can be one or more multifunctional aromatic vinyl monomers (100 weight percent), or no more than 98 weight percent, or no more than 95 weight percent, or no more than 90 weight percent, based on the total weight of the polymerizable material. In a certain aspect, the amount of the multifunctional aromatic vinyl monomer can be in the range of at least 80 weight percent to 100 weight percent, based on the total weight of the polymerizable material.

[0065] In another aspect, the polymerizable material of the photocurable composition of the present disclosure can further include at least one polymerizable monomer that does not include an aromatic ring, or a polymerizable monomer that does not include a vinyl group but includes other functional groups (e.g., one or more acrylate groups). As used herein, the term “acrylate monomer” relates to an acrylate monomer that is unsubstituted or alkyl-substituted, such as a methacrylate monomer.

[0066] The amount of the polymerizable material in the photocurable composition can be at least 50 weight percent, such as at least 60 weight percent, at least 70 weight percent, at least 80 weight percent, at least 85 weight percent, at least 90 weight percent, or at least 95 weight percent, based on the total weight of the photocurable composition. In another aspect, the amount of the polymerizable material can be no more than 99 weight percent, such as no more than 98 weight percent, or no more than 97 weight percent, or no more than 95 weight percent, or no more than 90 weight percent, based on the total weight of the photocurable composition. The amount of the polymerizable material can be a value between any of the minimum and maximum values described above. In one particular aspect, the amount of the polymerizable material can be at least 80 weight percent and no more than 97 weight percent.

[0067] In another embodiment, the polymerizable material of the photocurable composition can include a specific amount of a polymerizable oligomer or polymer.

[0068] The photocurable composition of the present disclosure can be suitable for inkjet adaptive planarization (IAP) or nanoimprint lithography (NIL).

[0069] IAP and NIL processes typically employ photocurable compositions having low viscosity. In one aspect, the photocurable compositions of the present disclosure can have a viscosity of no greater than 50 mPa-s, such as no greater than 40 mPa-s, no greater than 30 mPa-s, no greater than 25 mPa-s, no greater than 20 mPa-s. In another particular embodiment, the viscosity can be at least 2 mPa-s, or at least 3 mPa-s, or at least 5 mPa-s. As used herein, all viscosity values relate to viscosity measured using a Brookfield viscometer with the Brookfield method at a temperature of 23 °C.

[0070] The choice of polymerizable monomers can be made for the purpose of preparing a photocurable composition that can form a photocured layer having a high carbon content. In one aspect, the carbon content of the layer formed upon photocuring can be at least 71 wt%, or at least 72 wt%, or at least 73 wt%, based on the total weight of the photocured layer.

[0071] In another aspect, the photocured layer of the stack can have an Ohnishi number of no greater than 3.2, or no greater than 3.1, or no greater than 3.0, or no greater than 2.8, or no greater than 2.7, or no greater than 2.6. In another aspect, the Ohnishi number can be at least 1.8, such as at least 1.9, at least 2.0, at least 2.1, at least 2.2, or at least 2.3.

[0072] In one particular embodiment, the photocured layer can have a carbon content of at least 71% and an Ohnishi number of no greater than 3.1.

[0073] The photocurable composition can be suitable such that the photocured layer formed from the photocurable composition can have high thermal stability. In one aspect, the onset temperature of thermal degradation of the photocured layer can be at least 300 °C, or at least 330 °C, or at least 350 °C, or at least 375 °C, or at least 400 °C. As used herein, the onset temperature of thermal degradation is also referred to as the “initial degradation temperature T(X)” and relates to the temperature in the TGA curve where a deflection from the nearly linear plateau is first observed shortly before the sharp degradation drop of the sample.

[0074] In one embodiment, the first photocurable composition of the present disclosure can be substantially free of solvent.

[0075] As used herein, the term solvent, if not otherwise specified, relates to a compound that can dissolve or disperse the polymerizable monomers and hindered stabilizer, but does not polymerize itself during the photocuring of the photocurable composition. The term "substantially free of solvent" means herein that the amount of solvent is no greater than 5 wt.%, based on the total weight of the photocurable composition. In a certain particular aspect, the amount of solvent can be no greater than 3 wt.%, no greater than 2 wt.%, no greater than 1 wt.%, or the photocurable composition can be free of solvent, except for unavoidable impurities.

[0076] To initiate photocuring of the composition upon exposure to light, one or more photoinitiators can be included in the photocurable composition.

[0077] In a certain aspect, curing can also be performed by a combination of light and thermal curing.

[0078] The photocurable composition can further include one or more optional additives. Non-limiting examples of optional additives can be stabilizers, dispersants, solvents, surfactants, inhibitors, or any combination thereof.

[0079] In one embodiment, the photocurable composition can be applied on a substrate to form a photocured layer. As used herein, the combination of a substrate and a photocured layer overlaid on the substrate is referred to as a stack.

[0080] The present disclosure further relates to a method of forming a photocured layer. The method can include applying a layer of the photocurable composition described above on a substrate, contacting the photocurable composition with a template or a superstrate; irradiating the photocurable composition with light to form a photocured layer; and removing the template or the superstrate from the photocured layer.

[0081] The substrate and the cured layer can be subjected to additional processing, such as an etching process, to transfer an image of a pattern corresponding to one or both of the cured layer and / or a patterned layer under the cured layer into the substrate. The substrate can be further subjected to known steps and processes for device (article) fabrication, including, for example, curing, oxidizing, layer formation, deposition, doping, planarization, etching, formable material removal, dicing, bonding, and packaging, among others.

[0082] The photocured layer can further be used as an interlayer insulating film for a semiconductor device such as an LSI, a system LSI, a DRAM, a SDRAM, a RDRAM, or a D-RDRAM, or as a resist film used in a semiconductor manufacturing process.

[0083] As further demonstrated in the examples, it has been surprisingly found that photocurable compositions comprising a certain combination of polymerizable monomers and hindered stabilizers of formula (1) or formula (2) can have a desirable property profile particularly suitable for IAP and NIL processes.

[0084] Examples

[0085] The following non-limiting examples illustrate the concepts as described herein.

[0086] In the following examples, various photocurable compositions comprising different hindered stabilizers were prepared and tested. Table 1 contains a summary of the hindered stabilizers used in Examples 1-4:

[0087] Table 1:

[0088]

[0089] Example 1

[0090] Photocurable compositions were prepared by combining 100 parts of the polymerizable monomer 5-vinyl-1,3-benzyl acrylate (VMXDA), 3 parts of the photoinitiator Irgacure 819, 1 part of the surfactant FS3100 and different amounts of different types of hindered stabilizers. The following hindered stabilizers were used: hindered phenol HP1, hindered phenol HP2, hindered phenol HP3, hindered phenol HP4 and hindered amine HA1. Comparative photocurable composition C1 comprises all ingredients of compositions S1-S8, except for the hindered stabilizer.

[0091] The different types and amounts of hindered stabilizers used in the photocurable compositions, as well as the viscosity of the photocurable compositions and the T(X) of the layers after photocuring, are summarized in Table 2.

[0092] Table 2:

[0093]

[0094] ) estimated value

[0095] From the photocurable compositions, photocured layers were prepared by filling the space between two glass slides with the respective composition, wherein the distance between the two glass slides was 300 micrometers. Thereafter, the photocurable compositions were photocured by applying a radiation energy of 5 J.

[0096] Dynamic thermogravimetric analysis

[0097] The thermal stability of the photocured layers was investigated via dynamic thermogravimetric analysis (TGA) using a LINSEIS STA PT1000 instrument (Linseis Messgeraete GmbH, Germany). All measurements were performed under nitrogen at a rate of 5 liters / hour.

[0098] For TGA measurements, 25-35 mg of photocured sample was placed in a crucible and the initial weight was recorded. A reference crucible was used to monitor the weight change of the crucible due to temperature changes. The sample was heated at a rate of 20 °C / min, and the weight loss of the sample as a function of temperature increase was recorded at 1 second intervals. The relative weight percent change was calculated by dividing the weight loss by the total original weight of the sample.

[0099] The TGA curves of samples S1-S8 and comparative sample C1 were very similar. Figure 1 The TGA curves of samples S2, S6, S8 and C1 are illustrated. It can be seen that the first phase has only a very small almost linear weight loss up to the degradation temperature, and the second phase is very steep starting from the thermal degradation temperature until complete degradation of the sample (the curves are only shown up to 30% degradation). The initial degradation temperature T(X) of each curve was identified by determining the point of inflection from the established baseline of phase 1 of the TGA curve, and is listed in Table 2.

[0100] Isothermal thermogravimetric analysis

[0101] In addition, isothermal thermogravimetric analysis (TGA) was performed at a constant temperature of 350 °C for at least 30 minutes. The measurements were performed with the same TGA instrument described above and also under nitrogen. For each measurement, 25-35 mg of photocured sample was placed in a crucible and the initial weight was recorded. The temperature was rapidly increased to 350 °C (within 20 minutes), and when the temperature reached 350 °C, the weight loss was recorded over a period of 30 minutes. Figure 2 The relative weight loss of photocured samples S2, S6, S7, S8 and C1 at a constant temperature of 350 °C over a period of 30 minutes is shown. It can be seen that sample C1 has a much faster weight loss than samples S2, S6, S7 and S8.

[0102] The speed of the weight loss was characterized by converting the recorded data curves of each sample into a straight line, and expressing the slope of the line in the form of K value (Δ weight loss / minute), where a negative slope is expressed as a positive number. The K value can be an indicator of the thermal stability of the sample, the higher the K value, the less stable the sample. As shown in Table 3, comparative sample C1 has the highest K value, while samples S2, S6, S7 and S8 have lower K values. By normalizing the K values such that the comparative sample is set to 1, it can be seen that sample S8 has about 28% better thermal stability than comparative sample C1.

[0103] Table 3:

[0104]

[0105] Thermal shrinkage

[0106] The thermal shrinkage was measured by exposing the photocured layer to a baking treatment on a hot plate at 350°C for 2 minutes.

[0107] The photocured layer for the thermal shrinkage test was prepared by applying a layer of the liquid photocurable composition on a blank fused silica wafer and photocuring the liquid layer with a total radiation dose of 5 J of light at a wavelength of 365 nm. The test was designed so that the thickness of the photocured film obtained (before baking treatment) was about 500 nm. The baking treatment of the cured film was performed by placing it on a hot plate at a temperature of 350°C for 2 minutes. To calculate the thermal shrinkage, the thickness of the film before and after the baking treatment was measured using a JA Woolam Spectroscopic Ellipsometer M-2000 X-210 and the linear shrinkage (S b350 ) was calculated according to the following equation: S b350 =[(T p –T c ) / T p ]x 100%, T p is the thickness of the liquid film of the photocurable composition before the baking treatment and T c is the thickness of the photocured film after the baking.

[0108] The results of the thermal shrinkage measurement are summarized in Table 4. It can be seen that the highest shrinkage (2.6%) occurred for the comparative sample C1, while the lowest shrinkage 1.55% was obtained for sample S4 made by including 1 wt% of the hindered phenolic stabilizer HP4 (see Table 2), which corresponds to a reduction of the shrinkage of about 30%.

[0109] Table 4:

[0110]

[0111] Example 2

[0112] A photocurable composition was prepared comprising as polymerizable monomers 100 parts of 3,3' divinylbiphenyl (DVBPH), the photoinitiators OXE02 and Omnirad 1316 (3 parts of each photoinitiator) and 1 part of the surfactant FS3100. The respective photocurable compositions differed by using as hindered stabilizer the hindered phenol HP4 (sample S9) and the hindered amine HA2 (sample S10). The comparative sample C2 did not contain a hindered stabilizer. A summary of the cured compositions is shown in Table 5.

[0113] Table 5:

[0114]

[0115] A photocured layer was prepared from the photocurable composition and analyzed via dynamic TGA in the same manner as described in Example 1.

[0116] The TGA curve is shown in Figure 3 Figure 6. It can be seen that the sample S10 containing 1 wt% of the hindered amine HA2 has a higher initial thermal degradation temperature T(X) than the comparative sample C2. The increase in T(X) is about 26 °C.

[0117] An isothermal TGA was performed on the photocured sample S10 and the comparative sample C2 at 400 °C. As shown in Figure 4 it can be clearly seen that the addition of 1 wt% of the hindered amine stabilizer HA2 enhances the thermal stability and slows down the degradation.

[0118] Example 3

[0119] A third set of photocurable compositions was prepared using as polymerizable monomers 45 parts of 3,5-divinylbenzyl acrylate (DVBA); 30 parts of 5-vinyl-1,3-benzyl acrylate (VMXDA); and 25 parts of 3,4',5-trivinyl-1,1'-biphenyl (3VPH). All the photocurable compositions further contained 1 part of FS3100, 3 parts of Irgacure 819 and 3 parts of OXE02. The type of hindered stabilizer was varied, the hindered stabilizer of sample S11 was 3 wt% of the hindered amine HA1 and the hindered stabilizer of sample S12 was 3 wt% of the hindered phenol HP4. The comparative sample C3 did not contain a hindered stabilizer but contained all the other ingredients of samples S11 and S12. A summary of the photocurable compositions is shown in Table 6.

[0120] Table 6:

[0121]

[0122] A photocured layer was prepared from the photocurable composition and analyzed via dynamic TGA in the same manner as described in Example 1. The TGA curves (not shown) were similar to the samples of Example 1. The increase in the initial degradation temperature T(X) from C3 to S11 was about 21 °C.

[0123] Example 4

[0124] Investigation of the double bond conversion.

[0125] Fourier transform infrared spectroscopy (FTIR) was performed to measure the double bond conversion after the defined UV curing protocol of samples S1 to S8 (described in Example 1) and samples S11 and S12 (described in Example 3). For the measurement, the absorbance at 1405 cm -1decrease in the peak of the double bond C=C in the IR spectrum, while using the peak of the C-H benzene ring vibration at 713 cm -1 as an internal standard. The FTIR spectra from 4000 cm -1 to 625 cm -1 were recorded using a Thermo Nicolet 6700 FTIR with DTGS TEC detector.

[0126] For the measurements, an amount of 0.3 to 0.5 μΙ of sample was dropped on a NaCI window (25 mm x 25 mm) and then covered with another NaCI window of the same size. The intensity of the UV light applied was 38 mW / cm 2 for a time of 132 seconds, which corresponds to a dose of 5 J / cm 2 The C=C conversion was calculated by the peak ratio of the cured sample (after exposure to the curing regime) to the uncured sample (at the beginning of the measurement, before UV exposure).

[0127] Table 7 provides a summary of the measured C=C conversion of the test samples. It can be seen that the addition of the hindered stabilizers has no negative effect on the conversion when VMXDA is used as the polymerizable material. When the combination of DVBA / VMXDA / 3VPH is used as the polymerizable material (samples S11, S12, C3), the addition of the hindered stabilizer HA1 (sample S11) leads to an increase of the C=C conversion of 7.4% and the addition of the stabilizer HP4 (sample S12) leads to an increase of 5.6% relative to the comparative sample C3.

[0128] Table 7:

[0129]

[0130] Example 5

[0131] Storage life study.

[0132] A storage life test was performed to monitor the solution viscosity of the cured compositions S11, S12 and C3 (see also the description of the exact compositions in Example 3) over time. The monitoring was performed over a period of 9 weeks, wherein the sample bottles were opened once a week to allow oxygen to contact the samples.

[0133] A summary of the results is shown in Table 8. It can be seen that the compositions containing the hindered amine stabilizer HA1 or the hindered phenol stabilizer HP4 only have a very small change in viscosity after 9 weeks, wherein the increase in viscosity is not more than 0.6 mPa-s, while the comparative composition C3, which does not contain a hindered stabilizer of the present disclosure, already has an increase in viscosity of 1 mPa-s after 6 weeks.

[0134] Table 8:

[0135]

[0136] Carbon content and Westphal number

[0137] Other important properties for developing suitable photocurable compositions for IAP and NIL processes are carbon content and Ono number.

[0138] Table 9 shows a summary of calculated carbon content percentages and Ono numbers for representative photocurable compositions described in Examples 1, 2, and 3.

[0139] The Ono number (ON) is a known empirical parameter and is calculated as the ratio of the total number of atoms (N t ) in the repeating unit of the polymer divided by the difference between the number of carbon atoms (N O ) and the number of oxygen atoms (N t ) in the unit, ON = N C -N O . To calculate the Ono number, it is assumed that the cured material contains 100 wt% of polymeric monomer units formed by addition polymerization (no loss of atoms during polymerization).

[0140] Carbon content is calculated as a percentage of carbon atoms based on the total molecular weight of the compounds included in the photocurable composition.

[0141] As can be seen from Table 9, the carbon content of the photocurable compositions S1-S12 is 71% or more, up to 93%, and the Ono number is 3.0 or less.

[0142] Table 9:

[0143]

[0144] Viscosity measurement

[0145] Viscosity was measured with a Brookfield DV-11+Pro Viscometer using Spindle #18. For each viscosity measurement, a 6-7 ml sample was taken, added to the sample chamber, and allowed to equilibrate for 15-20 minutes to reach the target temperature of 23 °C. Viscosity was measured with Spindle #18 at a speed of 135 rpm. For each sample, measurements were repeated three times and an average value was calculated.

[0146] The descriptions and illustrations of the various embodiments described herein are intended to provide a general understanding of the structures of various embodiments. The descriptions and illustrations are not intended to serve as an all-inclusive and exhaustive description of devices and systems using the structures or methods described herein. Separate embodiments can also be provided in combination in a single embodiment, and, conversely, various features described in the context of a single embodiment can be provided separately or in any sub-combination. Furthermore, references to a specific value include each value within that range and each value. Many other embodiments will be apparent to those of ordinary skill in the art upon reading this description. Other embodiments can be employed and structural, logical, and electrical changes can be made without departing from the scope of the present disclosure. The disclosure is therefore to be considered in all respects as illustrative and not restrictive.

Claims

1. A photocurable composition comprising a polymerizable material, a hindered stabilizer, and a photoinitiator, wherein... The polymerizable material comprises at least one multifunctional aromatic vinyl monomer; and The hindered stabilizer is a hindered amine of formula (1) or a hindered phenol of formula (2). (1), or (2), Where X is H, CH3, or YZ; Y is CH2, O, S, or N; and Z is an organic substituent. R1 is H, CH3, OH, OR5, CO-CH3, or C(=O)R5; R2, R3, R4, and R5 are organic substituents.

2. The photocurable composition according to claim 1, wherein the hindered stabilizer comprises a hindered amine of formula (1), wherein X is YZ and Z comprises at least one reactive C=C group.

3. The photocurable composition according to claim 1, wherein the hindered stabilizer is a hindered amine selected from the group consisting of: ;or ;or ;or ;or ;or ;or ;or .

4. The photocurable composition according to claim 1, wherein the hindered stabilizer has a molecular weight of at least 600 g / mol.

5. The photocurable composition according to claim 1, wherein the hindered stabilizer is a hindered phenol selected from the group consisting of: ;or ;or ;or .

6. The photocurable composition according to claim 1, wherein the amount of the hindered stabilizer is at least 0.5% by weight and not more than 5% by weight, based on the total weight of the photocurable composition.

7. The photocurable composition according to claim 1, wherein the at least one polyfunctional aromatic vinyl monomer comprises divinylbiphenyl monomer DVBPh, or trivinylbiphenyl monomer TVBPh, or trivinylphenyl monomer TVPh, or a combination thereof.

8. The photocurable composition according to claim 1, wherein the at least one polyfunctional aromatic vinyl monomer comprises at least one vinyl group and at least one acrylate group.

9. The photocurable composition according to claim 8, wherein the polyfunctional aromatic vinyl monomer is selected from: ;or ;or ;or ;or ;or ;or ;or ;or .

10. The photocurable composition of claim 1, wherein the amount of the polyfunctional vinyl monomer is at least 80 by weight based on the total weight of the polymerizable material.

11. The photocurable composition of claim 10, wherein the amount of the polyfunctional vinyl monomer is at least 95% by weight based on the total weight of the polymerizable material.

12. The photocurable composition according to claim 1, wherein the amount of the polymerizable material is at least 90% by weight based on the total weight of the photocurable composition.

13. The photocurable composition according to claim 1, wherein the carbon content of the photocurable composition after photocuring is at least 71%.

14. The photocurable composition according to claim 1, wherein the viscosity of the photocurable composition is not greater than 30 mPa·s.

15. The photocurable composition according to claim 1, wherein the photocurable composition is substantially solvent-free.

16. A laminate comprising a substrate and a photocurable layer covering the substrate, wherein the photocurable layer is formed from the photocurable composition of claim 1.

17. The laminate according to claim 16, wherein the initial degradation temperature T(X) of the photocurable layer is at least 330°C.

18. A method for forming a photocurable layer on a substrate, comprising: A layer of a photocurable composition is applied to the substrate, wherein the photocurable composition comprises a polymerizable material, a hindered stabilizer, and a photoinitiator, wherein the polymerizable material comprises at least one polyfunctional aromatic vinyl monomer; and the hindered stabilizer is a hindered amine of formula (1) or a hindered phenol of formula (2): (1), or (2), X is H, CH3 or YZ, where Y is CH2, O or S or N, and Z is an organic substituent; R1 is H, CH3, OH, OR5 or CO-CH3 or COR5; R2, R3, R4, R5 are the same or different organic substituents; The photocurable composition is brought into contact with the cover plate or the embossing template; The photocurable composition is irradiated with light to form a photocurable layer; and Remove the cover plate or the embossing template from the photocured layer.

19. The method according to claim 18, wherein the initial degradation temperature T(X) of the photocurable layer is at least 330°C.

20. A method of manufacturing an article of articles, comprising: Forming a photocurable layer on a substrate as described in claim 18; A pattern is formed on the substrate; and The substrate on which the pattern has already been formed during the forming process; and The article is manufactured from the substrate processed in the process.

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