Photosensitive resin compositions and their cured films, as well as interlayer insulating films and semiconductor protective films using said cured films.

Abstract

The present invention aims to provide a photosensitive resin composition that exhibits high opening properties and excellent uniformity when formed into an opening pattern by exposure, development, and curing, and to provide a cured film formed by curing the film of the photosensitive resin composition, and an interlayer insulating film or semiconductor protective film using the cured film. To solve the above problems, a photosensitive resin composition is proposed, which contains at least a resin selected from the group consisting of polyimide, polybenzoxazole, polyamide, and precursors and copolymers thereof, a resin selected from the group consisting of phenolic resin and polyhydroxystyrene, and a photosensitizer. The resin film obtained by coating the photosensitive resin composition onto a substrate and subjecting it to heat treatment has a phase-separated structure.

Description

Technical Field

[0001] This invention relates to a photosensitive resin composition, and to a hardened film obtained from the photosensitive resin composition, as well as an interlayer insulating film and a semiconductor protective film using the hardened film. Background Technology

[0002] Polyimide resins and polybenzoxazole resins, which have excellent heat resistance or mechanical properties, are widely used in surface protective films or interlayer insulating films of semiconductor components in electronic devices.

[0003] One method for forming vias when polyimide is used as a surface protective film or interlayer insulating film for semiconductor devices is to use a positive photoresist as a mask for etching to form vias. However, this method involves the coating or stripping of the photoresist, which is cumbersome. Therefore, research has been conducted on heat-resistant materials that are also photosensitive, with the aim of streamlining the process.

[0004] As a photosensitive material, materials using quinone diazide compounds as photosensitizers have been proposed. Among them, as a method for increasing sensitivity, a system in which phenolic varnish resin or polyhydroxystyrene resin is added to a heat-resistant resin has been proposed (for example, Patent Document 1).

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2005-352004 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, when heat-resistant resin is mixed with phenolic varnish resin, the following problems arise: due to the low compatibility between the resins, the phase separation is large when the film is formed, and the pattern opening within the wafer surface becomes uneven when patterning is performed on the silicon wafer.

[0010] The present invention was made in view of the aforementioned issues, and its object is to provide a photosensitive resin composition that exhibits high openness and excellent uniformity when formed into a film, exposed, developed, and cured to create an open pattern, a cured film thereof, and an interlayer insulating film or semiconductor protective film using the cured film.

[0011] Technical means to solve the problem

[0012] To address the aforementioned issues, the photosensitive resin composition of the present invention comprises the following structure: a photosensitive resin composition containing at least a resin selected from the group consisting of polyimide, polybenzoxazole, polyamide, and precursors and copolymers thereof, a resin selected from the group consisting of phenolic resin and polyhydroxystyrene, and a photosensitizer; wherein the resin film obtained by coating the photosensitive resin composition onto a substrate and subjecting it to heat treatment has a phase-separated structure.

[0013] Furthermore, the present invention is a hardened film formed by curing the film of the photosensitive resin composition, and it is an interlayer insulating film or semiconductor protective film using the hardened film.

[0014] The effects of the invention

[0015] According to the present invention, a photosensitive resin composition with high sensitivity, excellent opening properties when formed into a film, exposed, developed, and cured to form an opening pattern, and excellent pattern uniformity can be obtained. Detailed Implementation

[0016] The present invention is a photosensitive resin composition comprising at least a resin selected from the group consisting of polyimide, polybenzoxazole, polyamide, and precursors and copolymers thereof (hereinafter, the resin is sometimes referred to as "resin (A)"), a resin selected from the group consisting of phenolic resin and polyhydroxystyrene (sometimes referred to as "resin (B)"), and a photosensitizer, wherein the photosensitive resin composition is coated on a substrate and subjected to heat treatment to obtain a resin film having a phase-separated structure.

[0017] The photosensitive resin composition of the present invention ensures solubility in alkaline developing solutions by containing alkali-soluble resins (resin (A) and / or resin (B) are equivalent to this). Here, alkali-soluble resin refers to a resin whose dissolution rate in an alkaline aqueous solution, which is a developing solution, is 50 nm / min or more relative to the film-like resin composition. More specifically, it refers to a pre-baked film with a thickness of 10 μm ± 0.5 μm formed by coating a solution of resin dissolved in γ-butyrolactone onto a silicon wafer, pre-baking it on a hot plate at 120°C for 4 minutes, immersing the pre-baked film in a 2.38% by mass tetramethylammonium hydroxide aqueous solution at 23°C ± 1°C for 1 minute, and then rinsing it with pure water, with a dissolution rate of 50 nm / min or more as determined by the reduction in film thickness at this time.

[0018] The photosensitive resin composition of the present invention achieves high heat resistance by using resin (A).

[0019] For example, polyimide precursors can be obtained by reacting tetracarboxylic acids, the corresponding tetracarboxylic dianhydrides, tetracarboxylic acid diester dichlorides, etc., with diamines, the corresponding diisocyanate compounds, or trimethylsilylated diamines. Polyimides can be obtained, for example, by dehydrating and ring-closing the polyimide precursor obtained by the above method using heating or chemical treatment with acids or alkalis.

[0020] Polyamides can be obtained by reacting dicarboxylic acids, the corresponding dicarboxylic acid dianhydrides, dicarboxylic acid diester dichlorides, etc., with diamines, the corresponding diisocyanate compounds, or trimethylsilyl diamines.

[0021] The polybenzoxazole precursor can be obtained by reacting diaminophenol with dicarboxylic acid, the corresponding dicarboxylic acid chloride, or an active dicarboxylic acid ester. Polybenzoxazole can also be obtained, for example, by dehydrating and ring-closing the polybenzoxazole precursor obtained by the aforementioned method using heating or chemical treatment with phosphoric anhydride, alkali, or carbodiimide compounds.

[0022] The resin (A) is preferably composed of at least one repeating unit as indicated below.

[0023] [Chemistry 1]

[0024]

[0025] X in the repeating unit 1 X represents an acid dianhydride residue. 2 X represents a tetracarboxylic acid residue or a tricarboxylic acid residue. 3 Y represents a dicarboxylic acid residue. 1 (OH) p Y 2 (OH) q and Y 3 (OH) r They represent diamine residues, respectively. p, q, and r represent integers in the range of 0 to 4, and R... 1 It represents a hydrogen atom or an organic group with 1 to 10 carbon atoms, where s represents 1 or 2.

[0026] Furthermore, examples of organic groups having 1 to 10 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonynyl, isopropyl, and tert-butyl.

[0027] Known compounds may be used as the compounds providing the dianhydride residue, tetracarboxylic acid residue, tricarboxylic acid residue, dicarboxylic acid residue, and diamine residue.

[0028] To improve the storage stability of the resin (A), it is preferable to use end-capping agents such as monoamines, acid anhydrides, monocarboxylic acids, monoacyl chloride compounds, and monoactive ester compounds to seal the ends of the main chain.

[0029] Known compounds may be used as monoamines, acid anhydrides, monocarboxylic acids, monoacyl chlorides, or monoactive esters.

[0030] When the total amount of diamine and monoamine introduced into the resin is set to 100 mol%, the proportion of monoamine used as a capping agent is preferably 0.1 mol% or more, particularly preferably 5 mol% or more, more preferably 40 mol% or less, and particularly preferably 30 mol% or less. The proportion of acid anhydride, monocarboxylic acid, monoacyl chloride compound, or monoactive ester compound used as a capping agent is preferably 0.1 mol% or more, particularly preferably 5 mol% or more, relative to the diamine content. On the other hand, in terms of maintaining a high molecular weight of the resin, it is preferably 100 mol% or less, particularly preferably 90 mol% or less. Multiple different end groups can also be introduced by reacting multiple capping agents.

[0031] The amount of end-capping agent corresponding to the end groups introduced into the resin (A) can be detected using the following methods. For example, it can be detected by dissolving the resin with the end groups in an acidic solution, decomposing it into amine and anhydride components as structural units, and then measuring them by gas chromatography (GC) or nuclear magnetic resonance (NMR). Alternatively, it can be detected directly using pyrolysis gas chromatography (PGC) or infrared spectroscopy. 13 C-NMR spectroscopy is used to detect resin components with terminal groups.

[0032] From the viewpoint of shortening the development time, the alkali dissolution rate (R(A)) of the resin (A) used in this invention is preferably 100 nm / min or more, more preferably 500 nm / min or more, and even more preferably 1000 nm / min or more. From the viewpoint of achieving good pattern shape, it is preferably 10,000 nm / min or less, more preferably 5,000 nm / min or less, and even more preferably 2,000 nm / min or less.

[0033] From the viewpoint of the mechanical properties of the hardened film, the weight-average molecular weight (Mw(A)) of the resin (A) converted to polystyrene is preferably 5,000 or more, more preferably 10,000 or more, and even more preferably 20,000 or more. From the viewpoint of alkali solubility, it is preferably 100,000 or less, more preferably 40,000 or less, and even more preferably 34,000 or less. Furthermore, the weight-average molecular weight can be determined by gel permeation chromatography (GPC).

[0034] The photosensitive resin composition of the present invention can achieve high sensitivity when processed into a film by including resin (B).

[0035] Examples of resins (B) include phenolic varnish resins, methyl phenolic resins, benzyl ether type phenolic resins, and polyhydroxystyrene, but are not limited to these as long as they are either phenolic resins or polyhydroxystyrene. Furthermore, two or more of these may be used.

[0036] Phenolic varnish resins are obtained by polycondensation of phenols and aldehydes such as formalin using known methods.

[0037] Polyhydroxystyrene used as resin (B) can be obtained, for example, by addition polymerization of phenolic derivatives formed by directly bonding unsaturated double bonds to a benzene ring using known methods.

[0038] From the viewpoint of shortening the development time, the alkali dissolution rate (R(B)) of the resin (B) used in this invention is preferably 500 nm / min or more, more preferably 1000 nm / min or more, and even more preferably 3000 nm / min or more. From the viewpoint of achieving good pattern shape, it is preferably 30,000 nm / min or less, more preferably 20,000 nm / min or less, and even more preferably 15,000 nm / min or less.

[0039] From the viewpoint of chemical resistance, the weight average molecular weight (Mw(B)) of the resin (B) converted to polystyrene is preferably 500 or more, more preferably 1,000 or more, and even more preferably 2,000 or more. From the viewpoint of alkali solubility, it is preferably 40,000 or less, more preferably 10,000 or less, and even more preferably 5,000 or less.

[0040] The phase separation structure described in this invention mainly refers to the phase separation state produced by mixing two or more polymers, which can be observed using the following methods.

[0041] As a method for observing phase-separated structures, a thin film sample with a thickness of approximately 100 nm is cut from a resin film (including a heat-treated resin film and a hardened film formed by curing the resin film) made of a photosensitive resin composition, and the cross-section of the resin film is observed using a transmission electron microscope. The observation site can be any location within the film thickness range. The observed image is binarized using image analysis software, and an image in which the area ratio (a phase ratio) of one of the binarized components is 20% to 70% of the entire image is defined as a phase-separated structure. The specific method for calculating the phase area ratio is described below.

[0042] From images obtained by observing resin film cross-sections using transmission electron microscopy at magnifications of 10,000–30,000x, a region equivalent to 2 μm square of the film area was extracted. The image was converted to 16 bits using the image analysis software "ImageJ" and then smoothed. A Gaussian filter with σ=2.0 was used. Next, background subtraction was performed. The rolling ball radius was set to 30 pixels. Then, image contrast was enhanced. The saturation pixel count was set to 0.35%. Next, the image was binarized by setting a threshold in the IsoData (Iterative Self-Organizing Data Analysis Technique Algorithm) Auto algorithm, and the area ratio of the colored region relative to the overall image was calculated. Images with a colored region area ratio of 20%–70% were designated as "phase-separated structures".

[0043] By having a phase area ratio ranging from 20% to 70% of the total image area, the degree of phase separation becomes suitable for obtaining the properties of each resin based on polymer mixing. A phase area ratio more preferably is 25% to 60% of the total image area, and even more preferably 30% to 50%. Within this range, high heat resistance or mechanical properties of resin (A) and high processability of resin (B) can be effectively obtained. Furthermore, since uniform alkali solubility is obtained in-plane during pattern processing, pattern opening with high in-plane uniformity can be obtained, suppressing cloudiness after development.

[0044] Furthermore, as a phase separation structure, in the observed image, for each individual phase detected by binarization using the image analysis software—that is, a unit in the image where one phase is surrounded by other parts (sometimes called an "island region")—when plotting with the area of ​​each individual phase as the horizontal axis and the sum of the brightness of the detected phases as the vertical axis, the slope 'a' of the approximate formula y=ax+b used for linear approximation of the plot is preferably -1.0 to -30.0, more preferably -1.5 to -10.0, and even more preferably -2.0 to -5.0. By using this range, the size of the phase separation region in the resin film becomes the size most suitable for improving heat resistance or mechanical properties, and sensitivity during processing. In addition, pattern opening with high in-plane uniformity can be obtained.

[0045] The method for calculating the slope 'a' will be explained in more detail. Similar to the method for observing the phase-separated structure, a thin film sample with a thickness of approximately 100 nm was cut from a resin film in which the photosensitive resin composition was formed into a film, and the cross-section of the resin film was observed using a transmission electron microscope. The observation site can be any location within the film thickness range. A 2 μm square region was cut from the obtained image, and the image was converted to 32 bits using the image analysis software "ImageJ". A Gaussian filter σ=2.0 was used to reduce noise, and a rolling sphere radius of 30 pixels was used for background subtraction. Next, the image was binarized by setting the threshold determination algorithm to "Default". For areas identified as black foregrounds, the area value of the island regions being analyzed was set to "100 pixels^2 - Infinity" to calculate the total brightness (Integrated Density, IntDen). Island regions not fully reflected in the image are considered outside the object. A scatter plot of the analysis results is drawn with the X-axis representing the area of ​​the island regions (Area) and the Y-axis representing the sum of brightness (IntDen). A first-order approximation (based on a linear function regression) for the plot is also drawn, with its slope set as slope a.

[0046] The photosensitive resin composition of the present invention is coated onto a substrate and then subjected to heat treatment to obtain a resin film with a phase-separated structure. Coating of the substrate can be achieved using methods such as spin coating, spray coating, roller coating, and die coating. The resin film thickness varies depending on the coating method, solid component concentration, viscosity, etc., but the film thickness after heat treatment is preferably 0.5 μm to 20 μm. The heat treatment can be performed immediately after coating (pre-baking) or after pattern processing (curing). The photosensitive resin composition of the present invention exhibits a phase-separated structure after pre-baking. Furthermore, it is preferable that the phase-separated structure is also present in the cured film state. Pre-baking is performed using a hot plate at a temperature of 80°C to 150°C for 1 to 30 minutes, preferably at 100°C to 130°C for 1 to 5 minutes, and particularly preferably at 120°C for 3 minutes. Curing can be performed using an oven, hot plate, infrared radiation, etc., applying a temperature of 150°C to 400°C to convert it into a heat-resistant resin film. The treatment is preferably carried out for 30 minutes to 3 hours while selecting a temperature and gradually increasing it in stages, or selecting a certain temperature range and continuously increasing it. When continuously heating and cooling, in order to obtain a phase-separated structure, the heating rate is preferably 1°C / min to 10°C / min, more preferably 2°C / min to 5°C / min. The cooling rate is preferably 1°C / min to 10°C / min, more preferably 2°C / min to 5°C / min. As an example, using an oven under nitrogen environment, after treating at 150°C for 30 minutes, the temperature is increased at a rate of 5°C / min, treated at 320°C for 1 hour, and then cooled to below 100°C at a rate of 4°C / min.

[0047] In the photosensitive resin composition of the present invention, in terms of easily achieving a phase-separated structure and making the surface roughness or contact angle described later within a preferred range, the content of resin (B) is preferably 15 to 200 parts by mass relative to 100 parts by mass of resin (A), more preferably 50 to 200 parts by mass, and even more preferably 100 to 150 parts by mass. Furthermore, the ratio of Mw(A) to Mw(B), i.e., (Mw(A) / Mw(B)), is preferably 1 to 20, more preferably 5 to 10, and even more preferably 7 to 10.

[0048] In the photosensitive resin composition of the present invention, in terms of easily achieving a phase-separated structure, all or part of the carboxyl terminus of the resin (A) has the structure of formula (1) or formula (2), and the solubility parameter (SP value) of the amine that reacts with the carboxyl terminus to provide the structure of formula (1) or formula (2) is preferably 8.0 to 16.0, more preferably 10.0 to 12.0. Furthermore, the amide or imide groups in formulas (1) and (2) show carbonyl groups derived from the carboxyl terminus. The solubility parameter (SP value) used is the value described in *Basic Science of Coatings* (page 65, by Yuji Harasaki, Maki Shoten). Additionally, for those documents that do not describe SP values, the values ​​were calculated based on the evaporation energy and molar volume of atoms and atomic groups generated by Fedors in *Basic Science of Coatings* (page 55, by Yuji Harasaki, Maki Shoten). As an amine or capping agent that reacts with the carboxyl terminus to provide a structure of formula (1) or formula (2), it is obtained by using, for example, a monoamine, in which case R 1 or R 2 This refers to a monoamine residue. When using a monoamine as a capping agent, the SP value of the monoamine is preferably 8.0 to 16.0, more preferably 10.0 to 12.0. For example, a polyimide precursor can be used as the resin (A) having the end represented by formula (1). For example, a polyimide can be used as the resin (A) having the end represented by formula (1). As the monoamine, aniline, 2-ethynylaniline, 3-ethynylaniline, 4-ethynylaniline, 5-amino-8-hydroxyquinoline, 1-hydroxy-7-aminonaphthalene, 1-hydroxy-6-aminonaphthalene, 1-hydroxy-5-aminonaphthalene, 1-hydroxy-4-aminonaphthalene, 2-hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene, 2-hydroxy-5-aminonaphthalene, 1-carboxyl-7-aminonaphthalene, 1-carboxyl-6-aminonaphthalene, 1-carboxyl-5-aminonaphthalene, 2-carboxyl-7-aminonaphthalene, 2-Carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzenesulfonic acid, 3-aminobenzenesulfonic acid, 4-aminobenzenesulfonic acid, 3-amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-aminophenol, 4-aminophenol, 2-aminobenzenethiophenol, 3-aminobenzenethiophenol, 4-aminobenzenethiophenol, 2-amino-4-tert-butylphenol, etc. Among these, aniline, 2-ethynylaniline, 3-ethynylaniline, 4-ethynylaniline, and 2-amino-4-tert-butylphenol are preferred. Two or more of these may also be used.

[0049] [Chemistry 2]

[0050]

[0051] In equation (1), R 1 Represents a monovalent organic group with 1 to 20 carbon atoms. It indicates a bond point with a dicarboxylic acid residue, a tricarboxylic acid residue, or a tetracarboxylic acid residue.

[0052] In equation (2), R 2 Represents a monovalent organic group with 1 to 20 carbon atoms. It indicates a bond point with a dicarboxylic acid residue, a tricarboxylic acid residue, or a tetracarboxylic acid residue.

[0053] As a monovalent organic group having 1 to 20 carbon atoms, examples include branched or straight-chain alkyl, alkylene, and alkynyl groups with a total carbon number of 1 to 20. In addition, groups in which a portion of these hydrogen atoms are substituted by oxyalkyl, thioalkyl, cyano, or halogen groups are also included.

[0054] In the photosensitive resin composition of the present invention, the difference between the surface roughness (Ra(1)) of the resin film obtained by coating the photosensitive resin composition onto a substrate and heat-treating it at 120°C for 3 minutes and the surface roughness (Ra(2)) of the film obtained by treating the resin film at 23°C for 1 minute using a 2.38% by mass aqueous solution of tetramethylammonium hydroxide (TMAH) is (Ra(2)-Ra(1)) is preferably 10 nm or more and 200 nm or less.

[0055] By limiting the range to a small difference in alkali solubility during development, a pattern opening with high in-plane uniformity can be obtained, and turbidity after development can be suppressed. In view of this, (Ra(2)-Ra(1)) is more preferably 20 nm to 100 nm, and more preferably 30 nm to 50 nm.

[0056] Furthermore, in the photosensitive resin composition of the present invention, the difference (θ(1) - θ(2)) between the static contact angle of water on the surface of the resin film obtained by coating the photosensitive resin composition onto a substrate and heating it at 120°C for 3 minutes and the static contact angle of water on the surface of the film after treating the resin film with 2.38% by mass of TMAH aqueous solution at 23°C for 1 minute is preferably 5° or more and less than 30°, more preferably 5° or more and less than 20°.

[0057] By defining the range, the difference in alkaline solubility during development is small, resulting in pattern opening with high in-plane uniformity and suppressing turbidity after development. Furthermore, the difference (θa(1)-θa(2)) between the advancing contact angle (θa(1)) of water in the membrane before treatment with the TMAH aqueous solution and the advancing contact angle (θa(2)) of the membrane surface after treatment with the TMAH aqueous solution at 23°C for 1 minute is preferably 5° or more and less than 20°, more preferably 5° or more and less than 15°. Additionally, the difference (θr(1)-θr(2)) between the retreating contact angle (θr(1)) of water and the retreating contact angle (θr(2)) of water on the membrane surface after treatment with the TMAH aqueous solution at 23°C for 1 minute is preferably 10° to 60°, more preferably 20° to 35°. By defining the range, the difference in alkaline solubility during development is small, resulting in pattern opening with high in-plane uniformity and suppressing turbidity after development.

[0058] Furthermore, the ratio (R(B) / R(A)) of the alkali dissolution rate (R(A)) of resin (A) to the alkali dissolution rate (R(B)) of resin (B) used in the photosensitive resin composition of the present invention is preferably 2.5 to 30. By setting this range, the phase separation structure can be easily achieved. The differences in surface roughness (Ra(2)-Ra(1)) and contact angles (θ(1)-θ(2)), (θa(1)-θa(2)), and (θr(1)-θr(2)) are preferably set within the range, resulting in high opening characteristics when forming an opening pattern through exposure, development, and curing. In addition, the pattern uniformity is excellent, and whitening after development can be suppressed. (R(B) / R(A)) is more preferably 4.0 to 15.

[0059] Furthermore, in the photosensitive resin composition of the present invention, the resin (A) has carboxyl groups and esterified carboxyl groups, and the ratio of esterified carboxyl groups relative to the total amount of carboxyl groups and esterified carboxyl groups of 100 mol% is preferably 50 mol% to 80 mol%, and more preferably 60 mol% to 75 mol%. By using the range described above, the alkali dissolution rate of the resin A can be preferably within a range, and the difference in surface roughness (Ra(2)-Ra(1)) and the difference in contact angle (θ(1)-θ(2)), (θa(1)-θa(2)), (θr(1)-θr(2)) can be preferably within a range. When exposed, developed, and hardened to form an open pattern, the opening performance is high, and the uniformity of the pattern is also excellent, which can suppress turbidity after development. One method for obtaining esterified carboxyl groups is as follows: during the polymerization of a resin, a solution is obtained by adding dropwise esterifying agents such as N,N-dimethylformamide dimethyl acetal, N,N-dimethylformamide diethyl acetal, and N,N-dimethylacetamide dimethyl acetal to a resin solution containing carboxyl groups for dilution.

[0060] The photosensitive resin composition of the present invention contains a photosensitizer. Preferably, a quinone diazide compound is used as the photosensitizer. Because the photosensitive resin composition of the present invention contains a quinone diazide compound, acid is generated in the ultraviolet-exposed section, increasing the solubility of the exposed section in an alkaline aqueous solution. Therefore, a positive pattern can be obtained by alkaline development after ultraviolet exposure.

[0061] Regarding the content of the photosensitizer used in this invention, from the viewpoint of achieving high sensitivity, it is preferably 1 part by mass or more, more preferably 3 parts by mass or more, relative to 100 parts by mass of resin (A). From the viewpoint of maintaining the mechanical properties of the hardened film, it is preferably 30 parts by mass or less, more preferably 20 parts by mass or less. Furthermore, sensitizers may be included as needed.

[0062] Examples of quinone diazide compounds include compounds formed by the ester bonding of quinone diazide sulfonic acid with a polyhydroxy compound, compounds formed by the ester bonding of quinone diazide sulfonic acid with a polyamino compound sulfonamide, and compounds formed by the ester bonding and / or sulfonamide bonding of quinone diazide sulfonic acid with a polyhydroxy or polyamino compound. All functional groups of these polyhydroxy or polyamino compounds may not be substituted with quinone diazide, but preferably 50 mol% or more of the functional groups are substituted with quinone diazide. By using such quinone diazide compounds, positive photosensitive resin compositions sensitive to i-rays (365 nm), h-rays (405 nm), and g-rays (436 nm) of mercury lamps, which are typically ultraviolet light, can be obtained.

[0063] In this invention, the quinone diazide compound preferably uses either 5-naphthoquinone diazidesulfonyl or 4-naphthoquinone diazidesulfonyl. Compounds containing both of these groups in the same molecule can be used, or compounds with different groups can be used in combination.

[0064] In addition, it may contain two or more quinone diazide compounds. This further increases the ratio of the dissolution rate of the exposed portion to the unexposed portion, resulting in a highly sensitive, positively typed photosensitive resin composition.

[0065] As quinone diazide compounds, compounds represented below are particularly preferred.

[0066] [Chemistry 3]

[0067]

[0068] In equation (3), Q is the structure or hydrogen atom represented by equation (4), and in equation (4), The key nodes represent the structure of equation (3).

[0069] When the total amount of Q is set to 100 mol%, the structure represented by formula (4) is preferably 90 mol% to 100 mol%. Furthermore, in the total amount of quinone diazide compound of formula (3) of 100 mol%, when the molar ratio of all Q being hydrogen atoms is set to a(0), the molar ratio of one of Q being the structure represented by formula (4) is set to a(1), the molar ratio of two of Q being the structure represented by formula (4) is set to a(2), and the molar ratio of all Q being the structure represented by formula (4) is set to a(3), preferably a(0) is 0 mol% to 15 mol%, a(1) is 0 mol% to 5 mol%, a(2) is 10 mol% to 20 mol%, and a(3) is 80 mol% to 90 mol%. Within these ranges, the difference in alkali solubility during development is small, resulting in high opening properties when forming an opening pattern through exposure, development, and hardening. Additionally, the pattern uniformity is excellent, and turbidity after development can be suppressed.

[0070] The quinone diazide compounds used in this invention can be synthesized by known methods. For example, a method of reacting 5-naphthoquinone diazidesulfonyl chloride with a polyhydroxy compound in the presence of triethylamine can be cited.

[0071] The resin film obtained by coating the photosensitive resin composition of the present invention onto a substrate and subjecting it to heat treatment has a phase-separated structure.

[0072] The photosensitive resin composition of the present invention preferably also contains a compound represented by any one of formulas (5) to (10) (hereinafter sometimes referred to as "compound (C)").

[0073] [Chemistry 4]

[0074]

[0075] In equation (5), R 3 R represents a hydrogen atom, a hydroxyl group, or a monovalent organic group having 1 to 10 carbon atoms. 4 and R 5 R represents either a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, respectively. 6 and R 7 Each of the four groups can be independently represented as a monovalent organic group with 1 to 4 carbon atoms.

[0076] In equation (6), R 8 R represents a monovalent organic group having 1 to 6 carbon atoms. 9 and R 10 Each of the four groups can be independently represented as a monovalent organic group with 1 to 4 carbon atoms.

[0077] In equation (7), R 11 and R 12 Each of the following can be used to independently represent a monovalent organic group having 1 to 10 carbon atoms.

[0078] In equation (8), R 13 To R 16 Each of the four groups can be independently represented as a monovalent organic group with 1 to 4 carbon atoms.

[0079] In equation (9), R 17 and R 18 Each of the following groups independently represents a monovalent organic group having 1 to 4 carbon atoms, where m is 1 or 2.

[0080] In equation (10), R 19 and R 20 Each of the four groups can be independently represented as a monovalent organic group with 1 to 4 carbon atoms.

[0081] In the formulas (5) to (10), as monovalent organic groups, examples include branched or straight-chain alkyl, alkylene, and alkynyl groups, which are ranges in terms of total carbon number, and also include groups in which a portion of these hydrogens are substituted with oxyalkyl, thioalkyl, cyano, or halogen groups.

[0082] By including compound (C) in the photosensitive resin composition of the present invention, the storage stability of the photosensitive resin composition is improved, and the size of the phase separation structure in the photosensitive resin composition can be stabilized relative to changes over time. Furthermore, as a resin film obtained by coating and heat treatment, a film with high uniformity of the continuous phase in the phase separation structure can be produced, i.e., the width of the continuous phase in the cross-sectional photograph is small and the width deviation is minimal. When the total mass of the photosensitive resin composition is set to 100% by mass, the content of compound (C) is preferably 0.1% to 1% by mass, or when the total mass of resin (A), resin (B), and compound (C) is set to 100% by mass, the content of compound (C) is preferably 0.1% to 1% by mass. A content of 0.1 parts by mass or more is advantageous in stabilizing the size of the phase separation structure relative to changes over time, while a content of 1 part by mass or less can suppress excessive increase in the alkali solubility of the unexposed portion of the photosensitive resin composition after the exposure process, resulting in pattern opening with high in-plane uniformity and suppressing turbidity after development.

[0083] Examples of compounds represented by formula (5) include, but are not limited to, N,N-dimethylpropionamide, N,N-dimethylisobutylamide, N,N-dimethylbutyramide, 2-methyl-N,N-dimethylbutyramide, N,N-dimethylpentanamide, N,N-dimethylisobutylamide, 2-methoxy-N,N-dimethylacetamide, 2-ethoxy-N,N-dimethylacetamide, 2-propoxy-N,N-dimethylacetamide, and 2-butoxy-N,N-dimethylacetamide.

[0084] Examples of compounds represented by formula (6) include, but are not limited to, 3-methoxy-N,N-dimethylpropionamide, 3-ethoxy-N,N-dimethylpropionamide, 3-propoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide, 3-methoxy-N,N-diethylpropionamide, and 3-methoxy-N,N-dipropylpropionamide.

[0085] Examples of compounds represented by formula (7) include, but are not limited to, 3-methoxy-3-methylbutyl acetate and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate.

[0086] Examples of compounds represented by formula (8) include N,N,N',N'-tetramethylurea, N,N,N',N'-tetraethylurea, and N,N-diethyl-N',N'-dimethylurea, but are not limited thereto.

[0087] Examples of compounds represented by formula (9) include, but are not limited to: N,N-dimethylacrylurea, N,N-diethylacrylurea, N,N-dipropylacrylurea, 1,3-dimethyl-2-imidazolidineone, 1,3-diethyl-2-imidazolidineone, 1,3-dipropyl-2-imidazolidineone.

[0088] Examples of compounds represented by formula (10) include methyl ethyl ketone, methyl propyl ketone, methyl isobutyl ketone, and diisobutyl ketone, but are not limited thereto.

[0089] The photosensitive resin composition of the present invention may also contain a thermal crosslinking agent as needed. Preferably, compounds having at least two alkoxymethyl groups and / or hydroxymethyl groups, or compounds having at least two epoxy groups and / or oxetyl groups, are used as thermal crosslinking agents, but are not limited to these. By containing these compounds, a condensation reaction occurs with the resin (A) during the curing process after patterning to form a crosslinked structure, thereby improving the mechanical properties of the cured film. Furthermore, two or more thermal crosslinking agents may be used, thereby enabling a wider range of designs.

[0090] Preferred examples of compounds having at least two alkoxymethyl groups and / or hydroxymethyl groups include, for example: DML-PC, DML-PEP, DML-OC, DML-OEP, DML-34X, DML-PTBP, DML-PCHP, DML-OCHP, DML-PFP, DML-PSBP, DML-POP, DML-MBOC, DML-MBPC, DML-MTrisPC, DML-BisOC-Z, DML-BisOCHP-Z, DML-BPC, DML-BisOC-P, DMOM-PC, DMOM-PTBP, DMOM-MBPC, TriML-P, TriML-35XL, TML-HQ, TML-BP, TML-pp-BPF, TML-BPE, TML-BPA The following products are available from various companies: TML-BPAF, TML-BPAP, TMOM-BP, TMOM-BPE, TMOM-BPA, TMOM-BPAF, TMOM-BPAP, HML-TPPHBA, HML-TPHAP, HMOM-TPPHBA, HMOM-TPHAP (all trade names, manufactured by Honshu Chemical Industry Co., Ltd.), "NIKALAC" (registered trademark) MX-290, NIKALAC MX-280, NIKALAC MX-270, NIKALAC MX-279, NIKALAC MW-100LM, and NIKALAC MX-750LM (all trade names, manufactured by Sanwa Chemical Co., Ltd.). More than one of these products may also be used.

[0091] In addition, preferred examples of compounds having at least two epoxy groups and / or oxetyl groups include, for example, bisphenol A type epoxy resin, bisphenol A type oxetyl resin, bisphenol F type epoxy resin, bisphenol F type oxetyl resin, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polymethyl (glycidyloxypropyl)siloxane and other epoxy-containing silicones, but are not limited to these. Specifically, examples include: "EPICLON" (registered trademark) 850-S, EPICLON HP-4032, EPICLON HP-7200, EPICLON HP-820, EPICLON HP-4700, EPICLON EXA-4710, EPICLON HP-4770, EPICLON EXA-859CRP, EPICLON EXA-1514, and EPICLON EX. Products such as A-4880, EPICLON EXA-4850-150, EPICLON EXA-4850-1000, EPICLON EXA-4816, and EPICLON EXA-4822 (all trade names, manufactured by Dai Nippon Ink & Chemical Co., Ltd.), "Rikaresin" (registered trademark) BEO-60E (trade name, manufactured by Shin Nippon Rikka Co., Ltd.), EP-4003S, and EP-4000S (trade name, manufactured by ADEKA Co., Ltd.) are available from their respective companies. Products may also contain two or more of these.

[0092] The content of the thermal crosslinking agent used in this invention is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and even more preferably 10 parts by mass or more, relative to 100 parts by mass of resin (A). From the viewpoint of maintaining mechanical properties such as elongation, it is preferably 300 parts by mass or less, and more preferably 200 parts by mass or less.

[0093] The photosensitive resin composition of the present invention may also contain solvents as needed. Preferred examples of solvents include: polar aprotic solvents such as N-methyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide, and dimethyl sulfoxide; ethers such as tetrahydrofuran, dioxane, propylene glycol monomethyl ether, and propylene glycol monoethyl ether; ketones such as acetone, methyl ethyl ketone, and diisobutyl ketone; esters such as ethyl acetate, butyl acetate, isobutyl acetate, propyl acetate, propylene glycol monomethyl ether acetate, and 3-methyl-3-methoxybutyl acetate; alcohols such as ethyl lactate, methyl lactate, diacetone alcohol, and 3-methyl-3-methoxybutanol; and aromatic hydrocarbons such as toluene and xylene. Two or more of these solvents may also be included.

[0094] From the viewpoint of resin dissolution, the solvent content is preferably 70 parts by mass or more, more preferably 100 parts by mass or more, relative to 100 parts by mass of resin (A). From the viewpoint of obtaining a suitable film thickness, the solvent content is preferably 1800 parts by mass or less, more preferably 1500 parts by mass or less.

[0095] The photosensitive resin composition of the present invention may also contain low-molecular-weight compounds having phenolic hydroxyl groups, if desired. By containing low-molecular-weight compounds having phenolic hydroxyl groups, the adjustment of alkali solubility during pattern processing becomes easier.

[0096] The content of low molecular weight compounds having phenolic hydroxyl groups is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, relative to 100 parts by mass of resin (A), and is preferably 30 parts by mass or less, more preferably 15 parts by mass or less, from the viewpoint of maintaining mechanical properties such as elongation.

[0097] The photosensitive resin composition of the present invention may, as needed, contain surfactants or esters such as ethyl lactate, propylene glycol monomethyl ether acetate, alcohols such as ethanol, ketones such as cyclohexanone and methyl isobutyl ketone, and ethers such as tetrahydrofuran and dioxane, for the purpose of improving wettability with the substrate. Some of these may also function as solvents.

[0098] The preferred content of these compounds used for the purpose of improving wettability with the substrate is 0.001 parts by mass or more relative to 100 parts by mass of resin (A), and from the viewpoint of obtaining a suitable film thickness, it is preferably 1800 parts by mass or less, more preferably 1500 parts by mass or less.

[0099] In addition, to improve adhesion to the silicon substrate, it may also contain silane coupling agents such as trimethoxyaminopropylsilane, trimethoxyepoxysilane, trimethoxyvinylsilane, and trimethoxythiolpropylsilane.

[0100] The preferred content of these compounds for improving adhesion to the silicon substrate is 0.01 parts by mass or more relative to 100 parts by mass of resin (A), and preferably 5 parts by mass or less from the viewpoint of maintaining mechanical properties such as elongation.

[0101] The viscosity of the photosensitive resin composition of the present invention is preferably 2 mPa. s~5000 mPa s. By achieving a viscosity of 2 mPa Adjusting the solid component concentration using methods above s makes it easy to obtain the desired film thickness. On the other hand, if the viscosity is 5000 mPa... With a viscosity below s, it is easy to obtain a coating film with high uniformity. Photosensitive resin compositions with this viscosity can be easily obtained, for example, by making the solids concentration 5% to 60% by mass.

[0102] Next, a method for forming a hardened film using the photosensitive resin composition of the present invention will be described.

[0103] The photosensitive resin composition of the present invention is coated onto a substrate. The substrate may be a silicon, ceramic, gallium arsenide, or a substrate on which metal is formed as electrodes and wiring, but is not limited to these. Coating methods include spin coating using a spinner, spray coating, and roll coating. Furthermore, the coating thickness varies depending on the coating method, the concentration of solid components in the composition, viscosity, etc., and is typically applied with a dried film thickness of 0.5 μm to 20 μm.

[0104] Next, the substrate coated with the photosensitive resin composition is subjected to heat treatment (pre-baking) to obtain a resin film of the photosensitive resin composition. Pre-baking is performed using a hot plate at a temperature of 80°C to 150°C for 1 to 30 minutes, preferably at 100°C to 130°C for 1 to 5 minutes.

[0105] When forming a resin pattern using the photosensitive resin composition, the film of the photosensitive resin composition is then exposed to chemical lines through a mask having the desired pattern. Chemical lines used for exposure include ultraviolet light, visible light, electron beams, X-rays, etc., but in this invention, mercury lamp i-rays (365 nm), h-rays (405 nm), and g-rays (436 nm) are preferably used.

[0106] Exposure can also be achieved by using methods such as halftone masks, or by changing the exposure area, mask, and exposure amount to perform multiple exposures, with the exposure amount varying depending on the exposure area on the substrate.

[0107] After exposure, development is performed using a developer. Preferably, the developer is an aqueous solution of an alkaline compound such as tetramethylammonium hydroxide, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine, dimethylaminoethyl acetate, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, or hexamethylenediamine. Alternatively, depending on the situation, polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, γ-butyrolactone, or dimethylacrylamide, alcohols such as methanol, ethanol, and isopropanol, esters such as ethyl lactate and propylene glycol monomethyl ether acetate, and ketones such as cyclopentanone, cyclohexanone, isobutyl ketone, and methyl isobutyl ketone, or a combination thereof, may be added to these alkaline aqueous solutions. After development, rinsing with water is preferred. Alcohols such as ethanol and isopropanol, as well as esters such as ethyl lactate and propylene glycol monomethyl ether acetate, can also be added to water for rinsing treatment.

[0108] After pre-baking, or after forming a resin pattern using the method described above, it is preferable to apply a temperature of 150°C to 400°C to perform a thermal crosslinking reaction, an imide ring-closure reaction, an oxazole ring-closure reaction, and then harden the film. This improves the heat resistance and chemical resistance of the hardened film. The heat treatment (curing) is preferably performed by gradually increasing the temperature in stages, or by continuously increasing the temperature within a certain range for 30 minutes to 3 hours.

[0109] When the surface roughness of the hardened film is set as Ra(3) and the surface roughness of the film after oxygen plasma treatment of the hardened film is set as Ra(4), the difference between these (Ra(4)-Ra(3)) is preferably 10 nm or more and 200 nm or less. The oxygen plasma treatment is performed using a plasma etching apparatus under the following conditions: gas type: oxygen, gas pressure: 20 Pa, gas flow rate: 100 sccm, power: 200 W, time: 60 seconds, and temperature: 25°C. By using the range of (Ra(4)-Ra(3)), pattern opening with high in-plane uniformity can be obtained, and the whitening of the film surface caused by plasma treatment can be suppressed. (Ra(4)-Ra(3)) is more preferably 10 nm or more and 50 nm or less, and even more preferably 10 nm or more and 30 nm or less.

[0110] The hardened film formed from the photosensitive resin composition of the present invention is suitable for use as a passivation film for semiconductors, a protective film for semiconductor devices, an interlayer insulating film for multilayer wiring for high-density mounting, an insulating layer for organic electroluminescent elements, and the like.

[0111] Example

[0112] The present invention will be described below with examples, but the invention is not to be limited to these examples. First, the evaluation method will be described. In the evaluation of the photosensitive resin composition (hereinafter sometimes referred to as "varnish"), it is used after filtering with a 1 μm polytetrafluoroethylene filter.

[0113] (1) Film thickness measurement

[0114] The thickness of the resin film on the substrate was measured using an optical interferometric thickness measuring device (Lambda Ace VM-1030 manufactured by Dai Nippon Screen Manufacturing Co., Ltd.). Furthermore, the refractive index was measured to be 1.629.

[0115] (2) Determination of the alkali dissolution rate of resin

[0116] The resin was dissolved in γ-butyrolactone (GBL) at a solids concentration of 35% by mass, and coated onto a 6-inch silicon wafer. The wafer was pre-baked at 120°C for 4 minutes to form a pre-baked film with a thickness of 10 μm ± 0.5 μm. The film was then immersed in a 2.38% by mass tetramethylammonium hydroxide aqueous solution at 23°C for 1 minute. The thickness of the dissolved film was calculated based on the film thickness before and after immersion, and the film thickness dissolved per minute was taken as the alkali dissolution rate. Furthermore, if the resin film completely dissolved within less than 1 minute, the time taken for dissolution was measured, and the film thickness dissolved per minute was calculated based on this time and compared to the film thickness before immersion; this was taken as the alkali dissolution rate of the resin.

[0117] (3) Determination of weight-average molecular weight

[0118] The resin was analyzed using a gel permeation chromatography (GPC) apparatus (Waters 2690-996, manufactured by Waters Ltd., Japan), with N-methyl-2-pyrrolidone (NMP) as the developing solvent. The weight-average molecular weight (Mw) was calculated in polystyrene form.

[0119] (4) Esterification rate determination

[0120] Dissolve the resin in dimethyl sulfoxide and use 1 H NMR was used for determination. The integral value of the peak value of the aromatic whole in the range of 6.0 ppm to 9.0 ppm was set as x, the integral value of the peak value near 3.8 ppm when 100 was set as z, the number of hydrogens of the ester group when the resin per unit weight (e.g. 1 g) was completely esterified was set as z, the number of hydrogens of the aromatic ring contained in the same weight of resin was set as y, and the esterification rate (%) was calculated as the value calculated by {(x / 100) ÷ (z / y)} × 100.

[0121] (5) Evaluation of pattern processability

[0122] After applying varnish to an 8-inch silicon wafer using a coating and developing apparatus (ACT-8, manufactured by Tokyo Electron, Inc.) via spin coating, a pre-baked film (resin film) with a thickness of 6 μm to 8 μm was formed at 120°C for 3 minutes. A mask with a 5 μm wide line and spatial pattern was then set in an i-ray stepper (NSR-2005i9C, manufactured by Nikon, Inc.) at 10 mJ / cm². 2 ~500 mJ / cm 2 At an exposure level of 10 mJ / cm 2 The pre-baked film was exposed using a step size. After exposure, the film was developed using an ACT-8 developing apparatus with a 2.38% (w / w) tetramethylammonium hydroxide aqueous solution, employing a double-layer development method with a spray time of 5 seconds and a layer time of 35 seconds. After rinsing with pure water, the film was spin-dried to obtain the developing solution. For the silicon wafer with the developing film, a cleaning oven (CLH-21CD-S manufactured by Koyo Heating Systems, Ltd.) was used for curing at 150°C for 30 minutes under a nitrogen flow (oxygen concentration below 20 ppm), followed by a further curing at 320°C for 1 hour. The silicon wafer was removed when the temperature reached below 50°C to obtain the cured film (hardened film).

[0123] The minimum exposure (Eth) for a 5 μm wide pattern opening is 10 mJ / cm. 2 Above and less than 100 mJ / cm 2 The pattern is set as A, and 100 mJ / cm 2 Above and below 150 mJ / cm 2 The pattern is set to B, and 150 mJ / cm 2 Above and less than 200 mJ / cm 2 The pattern is set as C, and 200 mJ / cm 2 The above is set as D.

[0124] (6) Evaluation of the in-plane uniformity of the pattern

[0125] Add 50 mJ / cm to the minimum exposure of the pattern opening in (5). 2 As the exposure amount used in the evaluation (evaluation exposure amount), in the same order as (5), wherein the exposure amount is fixed as the evaluation exposure amount, 9 points of exposure are performed at a distance of ±80 mm from the wafer center, ±60 mm from the wafer center, ±40 mm from the wafer center, ±20 mm from the wafer center, and the wafer center, and pattern processing is performed to obtain a cured film (hardened film).

[0126] The opening size of a pattern with a 5 μm wide opening in the spatial portion was measured using a digital microscope in the direction orthogonal to the line. The range of opening sizes (maximum value - minimum value) at 9 points was determined. Patterns with opening sizes less than 0.07 μm were designated as A, patterns with opening sizes greater than 0.07 μm but less than 0.1 μm were designated as B, patterns with opening sizes greater than 0.1 μm but less than 0.5 μm were designated as C, and patterns with opening sizes greater than 0.5 μm were designated as D.

[0127] (7) Evaluation of phase separation 1

[0128] A 100 nm thick pre-baked film sample obtained from (5) was processed using a focused ion beam (FIB) observation device (FB-2000 manufactured by Hitachi High Technology). The cross-section of the film was observed using a transmission electron microscope (JEM-F200 manufactured by NEC) at an accelerating voltage of 200 kV. A 2 μm square area was cut from the obtained image. The observed image was converted to 16 bits using the image analysis software "ImageJ" and then smoothed. At this time, the Gaussian filter σ=2.0 was set. Then, the image background was subtracted. The rolling sphere radius was set to 30 pixels. Then, the contrast of the image was emphasized. The saturation pixel count was set to 0.35%. Then, a threshold was set in IsoData Auto, and the area ratio of the colored part relative to the whole image was calculated as the phase separation area ratio. Images with an area ratio of 30% to 50% were set as A, images with an area ratio of 20% to 70% other than A were set as B, and all others were set as C.

[0129] In addition, for the developing film obtained in (5), the developing film with no white turbidity in the non-exposed area is designated as A, the developing film with slight white turbidity is designated as B, and the developing film with obvious white turbidity is designated as C.

[0130] (8) Evaluation of phase separation 2 (slope a)

[0131] A 2 μm square region was cut from the image obtained in (7), and the image was converted to 32 bits using the image analysis software "ImageJ". A Gaussian filter with σ=2.0 was used to reduce noise, and a rolling sphere radius of 30 pixels was used to subtract the background. Next, the image was binarized using a threshold-determined algorithm: preset. For areas identified as black foreground (where a unit in the image surrounded by other parts is defined as an "island region"), the area value of the island region being analyzed was set to "100 pixels^2 - infinity" to calculate the total brightness (IntDen). Among them, island regions not fully reflected in the image are considered outside the object. A scatter plot of the analysis results was drawn with the X-axis representing the area of ​​the island region (Area) and the Y-axis representing the total brightness (IntDen). The linear approximate curve of the plot was drawn, and its slope was taken as the slope a.

[0132] Let the slopes a range from -2.0 to -5.0 be designated as A, those excluding A range from -1.5 to -10.0 be designated as B, those excluding A and B range from -1.0 to -30.0 be designated as C, and all others be designated as D.

[0133] (9) Evaluation of surface roughness 1 (Ra(2)-Ra(1))

[0134] Using an atomic force microscope (AFM) (using a Bruker dimension icon), with the measurement range set to 500 nm square, the aspect ratio set to 2.00, and the measurement speed set to 1.00 Hz, the height difference of the resin film surface obtained in (5) was measured, and the difference between the maximum and minimum height values ​​was set as the surface roughness Ra(1). Similarly, the surface roughness of the developed film surface obtained in (5) was set as Ra(2), and (Ra(2) - Ra(1)) was calculated.

[0135] Let A be the (Ra(2)-Ra(1)) with a value of 30 nm to 50 nm, B be the (excluding A) with a value of 20 nm to 100 nm, and C be the (excluding A and B) with a value of 10 nm to 200 nm.

[0136] (10) Evaluation of contact angle

[0137] For the pre-baked membrane obtained in (5), the static contact angle θ(1), the advancing contact angle θa(1), and the retreating contact angle θr(1) of water were measured. For the developing membrane, the static contact angle θ(2), the advancing contact angle θa(2), and the retreating contact angle θr(2) of water were also measured in the same way.

[0138] Let A be the value of (θ(1)-θ(2)) which is greater than 5° and less than 20°, B be the value of (θ(1)-θ(2)) which is greater than 20° and less than 30°, and C be the value of (θ(1)-θ(2)) which is greater than 30°. There are no other values.

[0139] Let A be the value of (θa(1)-θa(2)) which is greater than 5° and less than 15°, B be the value of (θa(1)-θa(2)) which is greater than 15° and less than 20°, and C be the value of (θa(1)-θa(2)) which is greater than 20°. There are no other values.

[0140] Let A be the case where (θr(1)-θr(2)) is 20° to 35°, B be the case where (θr(1)-θr(2)) is 10° to 60°, and C be the case where (θr(1)-θr(2)) is 10° to 60°.

[0141] (11) Evaluation of phase separation 3

[0142] Except for replacing the pre-baked film obtained in (5) with the cured film obtained in (5), the phase separation area ratio is calculated in the same way as in "Evaluation of Phase Separation 1 in (7)". Area ratios of 30% to 50% are designated as A, those other than A are designated as B, and all others are designated as C.

[0143] (12) Evaluation of surface roughness 2 (Ra(4)-Ra(3))

[0144] For the cured film obtained in (5), the surface roughness (Ra(3)) was determined using the same method as described in “(9) Evaluation of Surface Roughness 1”. Next, the cured film was processed using a plasma etching apparatus (apparatus name) under the following conditions: gas type: oxygen, gas pressure: 20 Pa, gas flow rate: 100 sccm, power: 200 W, time: 60 seconds, and temperature: 25°C, and the surface roughness (Ra(4)) after processing was measured. Those with (Ra(4)-Ra(3)) of 10 nm to 30 nm were designated as A, those with 10 nm to 50 nm other than A were designated as B, and all others were designated as C.

[0145] [Synthetic Example 1] Synthesis of Diamine Compound 1 >

[0146] 164.8 g (0.45 mol) of 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (BAHF) was dissolved in 900 mL of acetone and 156.8 g (2.7 mol) of propylene oxide, and the solution was cooled to -15 °C. A solution prepared by dissolving 183.7 g (0.99 mol) of 3-nitrobenzoyl chloride in 900 mL of acetone was then added dropwise. After the addition was complete, the reaction was carried out at -15 °C for 4 hours, and then allowed to return to room temperature. The precipitated white solid was separated by filtration and dried under vacuum at 50 °C.

[0147] 270 g of the solid was placed in a 3 L stainless steel autoclave and dispersed in 2400 mL of methyl cellosolve. 5 g of 5% palladium-carbon was added. Hydrogen was introduced into the autoclave using a balloon, and the reduction reaction was carried out at room temperature. The reaction was considered complete after 2 hours when the balloon stopped shrinking. After the reaction, the palladium compound acting as a catalyst was removed by filtration, and the mixture was concentrated using a rotary evaporator to obtain diamine compound 1 represented by the following formula.

[0148] [Chemistry 5]

[0149]

[0150] [Synthesis Example 2] Synthesis of Resin (A-1)

[0151] Under a dry nitrogen stream, 62.04 g (0.20 mol) of bis(3,4-dicarboxyphenyl)ether dianhydride (ODPA) was dissolved in 630 g of NMP. 96.72 g (0.16 mol) of diamine compound 1, 2.49 g (0.01 mol) of 1,3-bis(3-aminopropyl)tetramethyldisiloxane, and 20 g of NMP were added, and the reaction was carried out at 20°C for 1 hour, followed by a reaction at 50°C for 2 hours. Next, 4.69 g (0.04 mol) of 4-ethynylaniline and 10 g of NMP were added as a capping agent, and the reaction was carried out at 50°C for 2 hours. Then, a solution obtained by diluting 38.13 g (0.32 mol) of N,N-dimethylformamide dimethyl acetal with 80 g of NMP was added dropwise over 10 minutes. After addition, the mixture was stirred at 50°C for 3 hours. After stirring, the solution was cooled to room temperature and then added to 5 L of water to obtain a precipitate. The precipitate was collected by filtration, washed three times with water, and then dried in a vacuum dryer at 80°C for 20 hours to obtain resin (A-1) powder.

[0152] [Synthesis Example 3] Synthesis of Resin (A-2)

[0153] Except that the amount of N,N-dimethylformamide dimethyl acetal was set to 40.51 g (0.34 mol), the resin (A-2) powder was obtained by the same method as in Synthesis Example 2.

[0154] [Synthesis Example 4] Synthesis of Resin (A-3)

[0155] Except that the amount of N,N-dimethylformamide dimethyl acetal was set to 44.09 g (0.37 mol), the resin (A-3) powder was obtained by the same method as in Synthesis Example 2.

[0156] [Synthesis Example 5] Synthesis of Resin (A-4)

[0157] Except that the amount of diamine compound 1 was set to 99.14 g (0.164 mol) and the amount of N,N-dimethylformamide dimethyl acetal was set to 40.51 g (0.34 mol), the resin (A-4) powder was obtained by the same method as in Synthesis Example 2.

[0158] [Synthesis Example 6] Synthesis of Resin (A-5)

[0159] Except that the amount of diamine compound 1 was set to 102.77 g (0.17 mol) and the amount of N,N-dimethylformamide dimethyl acetal was set to 40.51 g (0.34 mol), the resin (A-5) powder was obtained by the same method as in Synthesis Example 2.

[0160] [Synthesis Example 7] Synthesis of Resin (A-6)

[0161] Except that 4-ethynylaniline was replaced with 4.37 g (0.04 mol) of 3-aminophenol and the amount of N,N-dimethylformamide dimethyl acetal was set to 35.75 g (0.30 mol), the resin (A-6) powder was obtained by the same method as in Synthesis Example 2.

[0162] [Synthesis Example 8] Synthesis of Resin (A-7)

[0163] Except that the amount of 4-ethynylaniline replaced with 3-aminophenol was 4.37 g (0.04 mol) and the amount of N,N-dimethylformamide dimethyl acetal was set to 47.66 g (0.40 mol), the resin (A-7) powder was obtained by the same method as in Synthesis Example 2.

[0164] [Synthesis Example 9] Synthesis of Resin (A-8)

[0165] Except that the amount of 4-ethynylaniline replaced with 3-aminophenol was 4.37 g (0.04 mol) and the amount of N,N-dimethylformamide dimethyl acetal was set to 52.43 g (0.44 mol), the resin (A-8) powder was obtained by the same method as in Synthesis Example 2.

[0166] [Synthesis Example 10] Synthesis of Resin (A-9)

[0167] Except that the amount of 4-ethynylaniline replaced with 4-aminophenol was 4.37 g (0.04 mol) and the amount of N,N-dimethylformamide dimethyl acetal was set to 47.66 g (0.40 mol), the resin (A-9) powder was obtained by the same method as in Synthesis Example 2.

[0168] [Synthesis Example 11] Synthesis of Resin (A-10)

[0169] Except that the amount of 4-ethynylaniline replaced with 2-amino-4-tert-butylphenol was 6.61 g (0.04 mol) and the amount of N,N-dimethylformamide dimethyl acetal was set to 40.51 g (0.34 mol), the resin (A-10) powder was obtained by the same method as in Synthesis Example 2.

[0170] [Synthesis Example 12] Synthesis of Resin (A-11)

[0171] Under a dry nitrogen stream, 61.53 g (0.168 mol) of BAHF, 2.49 g (0.01 mol) of 1,3-bis(3-aminopropyl)tetramethyldisiloxane, and 4.37 g (0.04 mol) of 3-aminophenol as a capping agent were dissolved in 730 g of NMP. 62.04 g (0.20 mol) of ODPA and 20 g of NMP were added, and the mixture was reacted at 20°C for 1 hour, followed by a reaction at 50°C for 4 hours. The mixture was then stirred at 190°C for 5 hours. After stirring, the solution was cooled to room temperature and then added to 5 L of water to obtain a precipitate. The precipitate was collected by filtration, washed three times with water, and then dried in a vacuum dryer at 80°C for 20 hours to obtain resin (A-11) powder.

[0172] [Synthesis Example 13] Synthesis of Resin (B-1)

[0173] Under a dry nitrogen stream, 75.70 g (0.7 mol) of m-cresol, 21.63 g (0.2 mol) of p-cresol, 12.22 g (0.1 mol) of 2,5-dimethylphenol, 75.5 g (0.93 mol) of 37% formaldehyde aqueous solution, 0.63 g (0.005 mol) of oxalic acid dihydrate, and 260 g of methyl isobutyl ketone were loaded into the flask. The flask was then immersed in an oil bath, and a polycondensation reaction was carried out for 4 hours while the reaction solution was refluxed. The temperature of the oil bath was then increased over 3 hours. The pressure inside the flask was then reduced to 40 hPa–67 hPa to remove volatile components. The dissolved resin was then cooled to room temperature to obtain the polymer solid of resin (B-1).

[0174] [Synthesis Example 14] Synthesis of Resin (B-2)

[0175] Except that the amounts of m-cresol, p-cresol, and 2,5-dimethylphenol in Synthesis Example 13 were changed to 64.88 g (0.6 mol) of m-cresol, 32.44 g (0.3 mol) of p-cresol, and 12.22 g (0.1 mol) of 2,5-dimethylphenol, respectively, the synthesis was carried out in the same manner as in Synthesis Example 13 to obtain the polymer solid of resin (B-2).

[0176] [Synthesis Example 15] Synthesis of Resin (B-3)

[0177] Except that the amounts of m-cresol, p-cresol, and 2,5-dimethylphenol in Synthesis Example 13 were set to 32.44 g (0.3 mol) of m-cresol and 75.70 g (0.7 mol) of p-cresol, the same synthesis was carried out as in Synthesis Example 13 to obtain the polymer solid of resin (B-3).

[0178] [Synthesis Example 16] Synthesis of Resin (B-4)

[0179] In a mixed solution containing 2400 g of tetrahydrofuran and 2.56 g (0.04 mol) of sec-butyllithium as an initiator, 95.18 g (0.54 mol) of p-tert-butoxystyrene and 6.25 g (0.06 mol) of styrene were added, and polymerization was carried out while stirring for 3 hours. Then, 12.82 g (0.4 mol) of methanol was added to stop the polymerization. Next, to purify the polymer, the reaction mixture was injected into 3 L of methanol, and the precipitated polymer was dried and further dissolved in 1.6 L of acetone. 2 g of concentrated hydrochloric acid was added at 60 °C and the mixture was stirred for 7 hours. Then, water was injected to precipitate the polymer, deprotecting the p-tert-butoxystyrene to hydroxystyrene. After washing three times with water, the polymer was dried in a vacuum dryer at 50 °C for 24 hours to obtain resin (B-4).

[0180] [Synthetic Example 17] Synthesis of Quinone Diazide Compound 1

[0181] Under a dry nitrogen stream, 42.45 g (0.1 mol) of TrisP-PA (trade name, manufactured by Honshu Chemical Industry Co., Ltd.) and 75.23 g (0.28 mol) of 5-naphthoquinone diazidesulfonyl chloride (NAC-5, manufactured by Toyo Gosei Co., Ltd.) were dissolved in 1000 g of 1,4-dioxane. While cooling the reaction vessel in an ice bath, a liquid obtained by mixing 150 g of 1,4-dioxane with 30.36 g (0.3 mol) of triethylamine was added dropwise to prevent the system temperature from exceeding 35°C. After the addition, the mixture was stirred at 30°C for 2 hours. The triethylamine salt was filtered, and the filtrate was added to 7 L of pure water to obtain a precipitate. The precipitate was collected by filtration and washed with 2 L of 1% hydrochloric acid. Then, it was further washed twice with 5 L of pure water. The precipitate was dried in a vacuum dryer at 50°C for 24 hours to obtain a quinone diazide compound 1 represented by the following formula, which is 5-naphthoquinone diazide sulfonated on average in Q.

[0182] [Chemistry 6]

[0183]

[0184] In equation (3), Q 1 and Q 2 And Q 3 For the structure or hydrogen atom represented by equation (4), according to 1 1H NMR spectrum, Q in 100 mol% of total quinone diazide compounds. 1 and Q 2 And Q 3 The molar ratio a(0) of all hydrogen atoms is 0%, Q 1 and Q 2 And Q 3 One of them is the molar ratio of the structure represented by equation (4) a(1) is 0%, Q 1 and Q 2 And Q 3 The molar ratio of the two structures represented by equation (4) in equation (2) is 15%, Q 1 and Q 2 And Q 3 The molar ratio a(3) of all the structures represented by equation (4) is 85%.

[0185] [Synthetic Example 18] Synthesis of Quinone Diazide Compound 2

[0186] Except that the amount of 5-naphthoquinone diazidesulfonyl chloride was set to 69.86 g (0.26 mol), the same method as in Synthesis Example 17 was used to obtain an average of 2.6 quinone diazide compounds 2 represented by formula (3) that were 5-naphthoquinone diazidesulfonated in Q.

[0187] according to 1 1H NMR spectrum, Q in 100 mol% of total quinone diazide compounds. 1 and Q 2 And Q 3 The molar ratio a(0) of all hydrogen atoms is 0%, Q 1 and Q 2 And Q 3 One of them is the molar ratio of the structure represented by equation (4) a(1) of 5%, Q 1 and Q 2 And Q 3 The molar ratio of the two structures represented by equation (4) in equation (2) is 29%, Q 1 and Q 2 And Q 3 The molar ratio a(3) of all the structures represented by equation (4) is 66%.

[0188] For the alkali-soluble resins (A-1 to A-11, B-1 to B-4) obtained in Synthetic Examples 2 to 16, the alkali dissolution rate and weight-average molecular weight obtained by the method described above are shown in Table 1. In addition, for A-1 to A-11, the esterification rate and the SP value of the monoamine used as the capping agent are shown in Table 1.

[0189] [Table 1]

[0190]

[0191] [Examples 1-31, Comparative Examples 1-6]

[0192] As shown in Table 2, resin (A), resin (B), and compound (C) were mixed, and then 1.4 g of quinone diazide compound 1 or quinone diazide compound 2 obtained in Synthesis Example 17 or Synthesis Example 18, 1.1 g of NIKALAC MX-270 (trade name, manufactured by Sanwa Chemical Co., Ltd.), and 17.1 g of GBL were added and stirred to obtain varnish 1 to varnish 37. The mixing amount and mixing ratio of resin (A) and resin (B), the alkali dissolution rate ratio (R(B) / R(A)), and the weight average molecular weight ratio (Mw(A) / Mw(B)) are shown in Table 2, and the results obtained from the evaluations described in (5) to (12) are shown in Table 3.

[0193] The abbreviations for the materials used are listed below.

[0194] MPA: 3-Methoxy-N,N-Dimethylpropionamide

[0195] DMPA: N,N-Dimethylpropionamide

[0196] TMU: N,N,N',N'-Tetramethylurea

[0197] DMI: 1,3-Dimethyl-2-imidazolidineone

[0198] [Table 2-1]

[0199]

[0200] [Table 2-2]

[0201]

[0202] [Table 3-1]

[0203]

[0204] [Table 3-2]

[0205]

Claims

1. A photosensitive resin composition comprising at least a resin selected from the group consisting of polyimide, polybenzoxazole, polyamide, and precursors and copolymers thereof (hereinafter, sometimes referred to as "resin (A)"), a resin selected from the group consisting of phenolic resin and polyhydroxystyrene (hereinafter, sometimes referred to as "resin (B)"), and a photosensitizer. The resin film obtained by coating the photosensitive resin composition onto a substrate and then subjecting it to heat treatment has a phase-separated structure.

2. The photosensitive resin composition according to claim 1, wherein, When the surface roughness of the resin film obtained by coating the photosensitive resin composition onto a substrate and heat-treating it at 120°C for 3 minutes is defined as Ra(1), and the surface roughness of the film obtained by treating the resin film with a 2.38% by mass aqueous solution of tetramethylammonium hydroxide at 23°C for 1 minute is defined as Ra(2), the difference between these (Ra(2) - Ra(1)) is 10 nm or more and 200 nm or less.

3. The photosensitive resin composition according to claim 1 or 2, further comprising a compound represented by any one of formulas (5) to (10) (hereinafter sometimes referred to as "compound (C)"), When the total mass of the photosensitive resin composition is set to 100% by mass, the content of compound (C) is 0.1% to 1% by mass. [Chemistry 1] (R) 3 R represents a hydrogen atom, a hydroxyl group, or a monovalent organic group having 1 to 10 carbon atoms. 4 and R 5 R represents either a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, respectively. 6 R 7 R 9 R 10 and R 13 To R 20 R represents a monovalent organic group having 1 to 4 carbon atoms, respectively. 8 R represents a monovalent organic group having 1 to 6 carbon atoms. 11 and R 12 Each of these groups independently represents a monovalent organogroup with 1 to 10 carbon atoms. (m is 1 or 2).

4. The photosensitive resin composition according to claim 1 or 2, wherein, When the static contact angle of water on the surface of a resin film obtained by coating the photosensitive resin composition onto a substrate and heating it at 120°C for 3 minutes is set as θ(1), and the static contact angle of water on the surface of a film after treating the resin film with a 2.38% by mass aqueous solution of tetramethylammonium hydroxide at 23°C for 1 minute is set as θ(2), the difference between these (θ(1)-θ(2)) is 5° or more and less than 30°.

5. The photosensitive resin composition according to claim 1 or 2, wherein, When the weight-average molecular weight of resin (A) is set as Mw(A) and the weight-average molecular weight of resin (B) is set as Mw(B), Mw(A) is 10000~40000, Mw(A) / Mw(B) is 1~20.

6. The photosensitive resin composition according to claim 1 or 2, wherein, The carboxyl terminus of resin (A) has all or part of the structure of formula (1) or formula (2), and the solubility parameter (SP value) of the amine that reacts with the carboxyl terminus to provide the structure of formula (1) or formula (2) is 8.0 to 16.

0. [Chemistry 2] (In equation (1), R) 1 Represents a monovalent organic group with 1 to 20 carbon atoms. It indicates a bond point with a dicarboxylic acid residue, a tricarboxylic acid residue, or a tetracarboxylic acid residue. In equation (2), R 2 Represents a monovalent organic group with 1 to 20 carbon atoms. (This indicates a bond point with a dicarboxylic acid residue, a tricarboxylic acid residue, or a tetracarboxylic acid residue).

7. The photosensitive resin composition according to claim 1 or 2, wherein, When the dissolution rate of resin (A) in a 2.38% by mass tetramethylammonium hydroxide aqueous solution at 23°C is defined as R(A) (nm / min), and the dissolution rate of resin (B) in a 2.38% by mass tetramethylammonium hydroxide aqueous solution at 23°C is defined as R(B) (nm / min), R(A) ranges from 500 nm / min to 5000 nm / min. R(B) / R(A) is 2.5 to 30.

8. The photosensitive resin composition according to claim 1 or 2, wherein, Resin (A) has carboxyl groups and esterified carboxyl groups in its molecular structure. When the total amount of carboxyl groups and esterified carboxyl groups is set to 100 mol%, the proportion of esterified carboxyl groups is 50 mol% to 80 mol%.

9. The photosensitive resin composition according to claim 5, wherein, The Mw(A) / Mw(B) is 7-10.

10. The photosensitive resin composition according to claim 1 or 2, wherein, In a phase-separated structure of a resin film obtained by coating the photosensitive resin composition onto a substrate and subjecting it to heat treatment, when performing image analysis on an image of a cross-section of the resin film under the following conditions, one phase occupies 30% to 50% of the area relative to the overall image. <Image Analysis Conditions> A 2 μm square region was extracted from an image obtained by observing a cross-section of a heat-treated resin film using a transmission electron microscope. The image was then converted to 16-bit and smoothed using the image analysis software "ImageJ". A Gaussian filter with σ=2.0 was used. Next, background subtraction was performed, with a rolling sphere radius of 30 pixels. Image contrast was then enhanced, with a saturation pixel count of 0.35%. Finally, the image was binarized using an automated iterative self-organizing data analysis algorithm, and the area ratio of the colored region to the overall image was calculated.

11. A hardened film, formed by hardening the photosensitive resin composition as described in claim 1 or 2.

12. The hardened film according to claim 11, wherein, When the surface roughness of the hardened film as described in claim 11 is set to Ra (3), and the surface roughness of the film after oxygen plasma treatment of the hardened film is set to Ra (4), the difference between these (Ra (4) - Ra (3)) is more than 10 nm and less than 200 nm.

13. The hardened film according to claim 11, wherein, When performing image analysis on images of hardened film profiles under the following conditions, a phase occupies 30% to 50% of the area relative to the overall image. <Image Analysis Conditions> A 2 μm square region was extracted from an image obtained by observing a cross-section of the hardened film using a transmission electron microscope. The image was then converted to 16-bit and smoothed using the image analysis software "ImageJ". A Gaussian filter with σ=2.0 was used. Next, background subtraction was performed, with a rolling sphere radius of 30 pixels. Then, image contrast was enhanced, with a saturation pixel count of 0.35%. Finally, the image was binarized using an automated iterative self-organizing data analysis algorithm, and the area ratio of the colored region to the overall image was calculated.

14. An interlayer insulating film using the hardened film as described in claim 11.

15. A semiconductor protective film using the hardened film as described in claim 11.

Images