WO2024101295A1

WO2024101295A1 - Production method for cured product, production method for laminate, production method for semiconductor device, and semiconductor device

Info

Publication number: WO2024101295A1
Application number: PCT/JP2023/039835
Authority: WO
Inventors: 裕樹奈良
Original assignee: 富士フイルム株式会社
Priority date: 2022-11-08
Filing date: 2023-11-06
Publication date: 2024-05-16

Abstract

A production method for a cured product according to the present invention includes a pressure reduction step for putting a resin layer under a pressure of less than 101,325 Pa and a heating step for heating the resin layer under said pressure, wherein the resin layer is formed from a resin composition that includes a polyimide precursor and a solvent, and a specific condition is met. A production method for a laminate according to the present invention includes the production method for a cured product. A production method for a semiconductor device according to the present invention includes the production method for a cured product. A semiconductor device according to the present invention includes a cured product obtained by means of the production method for a cured product.

Description

Method for manufacturing a cured product, method for manufacturing a laminate, method for manufacturing a semiconductor device, and semiconductor device

The present invention relates to a method for producing a cured product, a method for producing a laminate, a method for producing a semiconductor device, and a semiconductor device.

2. Description of the Related Art Nowadays, resin materials produced from resin compositions containing resins are being used in various fields.
For example, polyimide is used in various applications due to its excellent heat resistance and insulating properties. The applications include, but are not limited to, materials for insulating films and sealing materials, or protective films for semiconductor devices for mounting. Polyimide is also used as a base film or coverlay for flexible substrates.

For example, in the above-mentioned applications, polyimide is used in the form of a resin composition containing a polyimide precursor.
Such a resin composition is applied to a substrate, for example by coating, to form a resin layer, and then, if necessary, exposed to light, developed, and then heated, whereby a cured product can be formed on the substrate.
The polyimide precursor is cyclized by heating to become a polyimide in the cured product.
Since the resin composition can be applied by a known coating method, etc., it can be said to have excellent adaptability in manufacturing, for example, high degree of freedom in designing the shape, size, application position, etc. of the resin composition when applied. In addition to the high performance of polyimide, from the viewpoint of such excellent adaptability in manufacturing, the above-mentioned resin composition is expected to be increasingly applied in industrial applications.

For example, Patent Document 1 describes a photosensitive resin composition that contains a polyimide resin precursor having a repeating unit structure represented by the following general formula (1), a photosensitizer, a dispersible compound that is dispersible in the polyimide resin precursor, and a solvent.

JP 2001-323099 A

When a resin layer containing a polyimide precursor is heated to form a cured product, it is necessary to improve the heat resistance reliability and chemical resistance of the resulting cured product.

The present invention aims to provide a method for producing a cured product that provides a cured product with excellent heat resistance reliability and chemical resistance, a method for producing a laminate that includes the method for producing the cured product, a method for producing a semiconductor device that includes the method for producing the cured product, and a semiconductor device that includes a cured product obtained by the method for producing the cured product.

Examples of typical embodiments of the present invention are given below.
<1> A decompression step of exposing the resin layer to a pressure lower than 101,325 Pa; and
a heating step of heating the resin layer under the pressure,
the resin layer is a layer formed from a resin composition containing a polyimide precursor and a solvent,
A method for producing a cured product, which satisfies at least one of the following conditions 1 and 2:
Condition 1: The resin composition further contains a compound A having at least one bond selected from a urethane bond and a urea bond, and at least one functional group selected from a tert-butyl group, a hydroxyl group, and a group containing an ethylenically unsaturated bond.
Condition 2: The method includes a step of contacting the resin layer with a treatment liquid containing the compound A prior to the depressurization step.
<2> The method for producing a cured product according to <1>, further comprising, prior to the decompression step, a step of exposing a photosensitive resin layer formed from the resin composition further containing a photopolymerization initiator, and a step of developing the exposed photosensitive resin layer to obtain the resin layer.
<3> The method for producing a cured product according to <2>, wherein the photopolymerization initiator includes a compound having a structure represented by the following formula (PPI-1):

In formula (PPI-1), R ¹ is an organic group having 1 to 9 carbon atoms, R ² is a methyl group or a phenyl group, R ³ is each independently an organic group having 1 to 9 carbon atoms, and n is an integer of 0 to 5.
<4> The method for producing a cured product according to any one of <1> to <3>, wherein the decompression step is a step of exposing the resin layer to a pressure of 0.07 MPa or less.
<5> The method for producing a cured product according to any one of <1> to <4>, wherein the heating temperature in the heating step is 140° C. or higher.
<6> The method for producing a cured product according to any one of <1> to <5>, wherein the compound A includes at least one compound selected from the group consisting of a compound having a tert-butyl group and a urethane bond, and a compound having a urea bond, two or more hydroxy groups, and a group containing an ethylenically unsaturated bond.
<7> The method for producing a cured product according to any one of <1> to <6>, wherein the resin layer further contains an azole compound.
<8> The method for producing a cured product according to any one of <1> to <7>, wherein the resin layer contains an organometallic complex containing at least one metal atom selected from titanium, zirconium, and hafnium.
<9> The method for producing a cured product according to any one of <1> to <8>, wherein the obtained cured product has a linear thermal expansion coefficient of 55 ppm/K or less in the range of 25° C. to 125° C.
<10> The method for producing a cured product according to any one of <1> to <9>, wherein the obtained cured product has a tensile modulus at 25°C of 3.0 GPa or more.
<11> The method for producing a cured product according to any one of <1> to <10>, wherein the obtained cured product has a tensile elongation at 25°C of 40% or more.
<12> A method for producing a laminate, comprising the method for producing a cured product according to any one of <1> to <11>.
<13> A method for producing a semiconductor device, comprising the method for producing a cured product according to any one of <1> to <11>.
<14> A semiconductor device comprising a cured product obtained by the method for producing a cured product according to any one of <1> to <11>.

The present invention provides a method for producing a cured product that provides a cured product with excellent heat resistance reliability and chemical resistance, a method for producing a laminate that includes the method for producing the cured product, a method for producing a semiconductor device that includes the method for producing the cured product, and a semiconductor device that includes a cured product obtained by the method for producing the cured product.

FIG. 2 is a schematic diagram of a test vehicle used in biased HAST tests in the examples.

Hereinafter, the main embodiments of the present invention will be described, however, the present invention is not limited to the embodiments explicitly described.
In this specification, a numerical range expressed using the symbol "to" means a range that includes the numerical values before and after "to" as the lower limit and upper limit, respectively.
In this specification, the term "step" includes not only an independent step, but also a step that cannot be clearly distinguished from another step, so long as the intended effect of the step can be achieved.
In the description of groups (atomic groups) in this specification, when there is no indication of whether they are substituted or unsubstituted, the term encompasses both unsubstituted groups (atomic groups) and substituted groups (atomic groups). For example, an "alkyl group" encompasses not only alkyl groups that have no substituents (unsubstituted alkyl groups) but also alkyl groups that have substituents (substituted alkyl groups).
In this specification, unless otherwise specified, the term "exposure" includes not only exposure using light but also exposure using particle beams such as electron beams and ion beams. Examples of light used for exposure include the bright line spectrum of a mercury lamp, far ultraviolet light represented by an excimer laser, extreme ultraviolet light (EUV light), X-rays, electron beams, and other actinic rays or radiation.
In this specification, "(meth)acrylate" means both or either of "acrylate" and "methacrylate", "(meth)acrylic" means both or either of "acrylic" and "methacrylic", and "(meth)acryloyl" means both or either of "acryloyl" and "methacryloyl".
In this specification, in the structural formulae, Me represents a methyl group, Et represents an ethyl group, Bu represents a butyl group, and Ph represents a phenyl group.
In this specification, the total solid content refers to the total mass of all components of the composition excluding the solvent, and in this specification, the solid content concentration refers to the mass percentage of the other components excluding the solvent with respect to the total mass of the composition.
In this specification, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are values measured using gel permeation chromatography (GPC) unless otherwise specified, and are defined as polystyrene equivalent values. In this specification, the weight average molecular weight (Mw) and the number average molecular weight (Mn) can be determined, for example, by using HLC-8220GPC (manufactured by Tosoh Corporation) and using guard columns HZ-L, TSKgel Super HZM-M, TSKgel Super HZ4000, TSKgel Super HZ3000, and TSKgel Super HZ2000 (all manufactured by Tosoh Corporation) connected in series as columns. Unless otherwise specified, these molecular weights are measured using THF (tetrahydrofuran) as the eluent. However, when THF is not suitable as the eluent, such as when the solubility is low, NMP (N-methyl-2-pyrrolidone) can also be used. In addition, unless otherwise specified, detection in GPC measurement is performed using a UV (ultraviolet) ray (wavelength 254 nm detector).
In this specification, when the positional relationship of each layer constituting the laminate is described as "upper" or "lower", it is sufficient that there is another layer above or below the reference layer among the multiple layers being noted. That is, a third layer or element may be interposed between the reference layer and the other layer, and the reference layer does not need to be in contact with the other layer. Unless otherwise specified, the direction in which the layers are stacked on the substrate is referred to as "upper", or, in the case of a resin composition layer, the direction from the substrate to the resin composition layer is referred to as "upper", and the opposite direction is referred to as "lower". Note that such a vertical direction is set for the convenience of this specification, and in an actual embodiment, the "upper" direction in this specification may be different from the vertical upward direction.
In this specification, unless otherwise specified, the composition may contain, as each component contained in the composition, two or more compounds corresponding to that component. Furthermore, unless otherwise specified, the content of each component in the composition means the total content of all compounds corresponding to that component.
In this specification, unless otherwise specified, the temperature is 23° C., the pressure is 101,325 Pa (1 atm), and the relative humidity is 50% RH.
As used herein, combinations of preferred aspects are more preferred aspects.

(Method for producing the cured product)
The method for producing a cured product of the present invention includes a decompression step of exposing a resin layer to a pressure lower than 101,325 Pa, and a heating step of heating the resin layer under the above pressure, wherein the resin layer is a layer formed from a resin composition containing a polyimide precursor and a solvent, and satisfies at least one of the following conditions 1 and 2:
Condition 1: The resin composition further contains a compound A having at least one bond selected from a urethane bond and a urea bond, and at least one functional group selected from a tert-butyl group, a hydroxyl group, and a group containing an ethylenically unsaturated bond.
Condition 2: The method includes a step of contacting the resin layer with a treatment liquid containing the compound A prior to the depressurization step.

The method for producing a cured product of the present invention can be used, for example, to form insulating films for semiconductor devices, interlayer insulating films for redistribution layers, stress buffer films, etc., and is preferably used to form interlayer insulating films for redistribution layers.

According to the method for producing a cured product of the present invention, a cured product having excellent heat resistance reliability and chemical resistance can be obtained.
The mechanism by which the above effects are obtained is unclear, but is speculated to be as follows.

By carrying out a decompression step in the method for producing a cured product of the present invention, low molecular weight components such as residual solvent and decomposition products of the polymerization initiator in the film are volatilized, making it possible to produce a cured product with little outgassing in subsequent steps.
In addition, a thermal base generator is generally used to heat-cure the polyimide precursor. The thermal base generator is decomposed upon heating to generate a base, which is believed to act as a catalyst to promote the cyclization reaction (imidization) of the polyimide precursor.
When the amount of outgassing is reduced by reducing the pressure as described above, if a typical thermal base generator is used, the base generator or a part of the base generated by decomposition of the base generator is also vaporized by reducing the pressure, which may result in an insufficient imidization rate.
Therefore, the present inventors have found that the above-mentioned compound A can be used as a thermal base generator that is unlikely to volatilize even under reduced pressure (and further under reduced pressure and heating). Compound A has good affinity for a film containing a polyimide precursor and therefore is unlikely to volatilize under reduced pressure, and can simultaneously achieve the effects of suppressing the generation of outgassing and improving the imidization rate.
In particular, when the compound A has a structure in which a basic group (particularly, an amino group) is protected by a protecting group (t-BOC, Fmoc, etc., particularly t-BOC), the presence of the protecting group makes the compound less likely to volatilize until a high temperature is reached, and at a high temperature, the compound is deprotected to generate a base, which is considered to contribute to an increase in the imidization rate.
Furthermore, when the compound A has a hydroxyl group, it forms a bond with the polyimide precursor through an ester bond or the like, and is therefore less likely to volatilize in a decompression step, and is decomposed upon heating to generate a base, which is thought to contribute to an increase in the imidization rate.
Furthermore, when the above urea or urethane compound has a radical polymerizable group, it is polymerized by exposure to light or heat and is therefore less likely to volatilize in a reduced pressure step, but is decomposed upon heating to generate a base, which is thought to contribute to an increase in the imidization rate.
As a result, it is believed that the effect of improving the heat resistance reliability and chemical resistance of the cured product can be obtained.

Patent Document 1 does not describe a method for producing a cured product that includes a decompression step and satisfies the above-mentioned conditions 1 and 2.

The method for producing the cured product of the present invention is described in detail below.

<Decompression step>
The method for producing a cured product of the present invention includes a decompression step of exposing a resin layer to a pressure lower than 101,325 Pa.
The resin layer will be described in detail later.
The pressure in the decompression step may be lower than 101,325 Pa, but the decompression step is preferably a step of exposing the resin layer to a pressure of 0.07 MPa or less, and more preferably a step of exposing the resin layer to a pressure of 0.053 MPa or less. The lower limit of the pressure is not particularly limited, and may be 0 MPa or more. In other words, it may be a vacuum.
The pressure in the decompression may be reduced stepwise or may be reduced to the desired pressure in one go.
The pressure reduction may be carried out once or multiple times.

In the decompression step, the time for which the resin layer is exposed to the above pressure is preferably from 10 to 420 minutes, more preferably from 20 to 360 minutes, and even more preferably from 30 to 300 minutes.
Alternatively, the heating step may be started after leaving the mixture under reduced pressure at a temperature close to room temperature.
The standing time is preferably from 10 to 420 minutes, more preferably from 20 to 360 minutes, and even more preferably from 30 to 300 minutes.
In this specification, unless otherwise specified, room temperature means 25°C, and a temperature near room temperature means a temperature of about 25°C±10°C.
The temperature in the decompression step is not particularly limited, but is preferably 20° C. or higher.
The pressure reduction rate is preferably from 50 to 1000 Pa/s, more preferably from 75 to 800 Pa/s, and even more preferably from 100 to 500 Pa/s.
It is also preferable to increase the pressure back to the pressure in the space, such as inside the room, after the decompression step is completed.
The rate of increase in the pressure is preferably 50 to 1000 Pa/s, more preferably 75 to 800 Pa/s, and even more preferably 100 to 500 Pa/s.
The pressure reduction rate is preferably from 50 to 1000 Pa/s, more preferably from 75 to 800 Pa/s, and even more preferably from 100 to 500 Pa/s.
The pressure reducing means is not particularly limited, and examples thereof include a known vacuum pump.

The pressure reduction may be performed in an inert gas atmosphere such as a nitrogen atmosphere or an Ar atmosphere, or in the air.

<Heating process>
The method for producing a cured product of the present invention includes a heating step of heating the resin layer under the pressure reduced in the above-mentioned depressurizing step.
That is, at least a part of the heating step is carried out under a pressure lower than 101,325 Pa. The preferred range of the pressure is as described above.
In addition, the heating process, including increasing the temperature, maintaining the temperature at the maximum heating temperature, and decreasing the temperature, may all be carried out under the above pressure, or only a part of the process may be carried out under the above pressure.
In the above embodiment, it is preferable that at least the heating at the maximum heating temperature in the heating step is carried out under the above pressure.
In one preferred embodiment of the present invention, the temperature increase in the heating step and the maintenance at the maximum heating temperature are carried out under the above pressure.
In one preferred embodiment of the present invention, the heating step is performed under the above pressure during the temperature increase, the maintenance at the maximum heating temperature, and the temperature decrease.
In the heating step, the polyimide precursor cyclizes to form the polyimide.
In the heating step, the compound A is preferably decomposed to generate an amine. The heating step is preferably a step in which the cyclization of the polyimide precursor is promoted by the action of the amine.
In the heating step, it is preferable that polymerization of unreacted polymerizable groups in the polyimide precursor or the polymerizable compound described below also proceeds.
The heating temperature (maximum heating temperature) in the heating step is preferably 140° C. or higher, more preferably 150° C. or higher, even more preferably 160° C. or higher, and particularly preferably 170° C. or higher. It may also be 200° C. or higher.
The upper limit of the heating temperature is preferably 300° C. or less, more preferably 250° C. or less, and even more preferably 230° C. or less.

The heating step is preferably performed at a temperature rise rate of 1 to 12° C./min from the temperature at the start of heating to the maximum heating temperature. The temperature rise rate is more preferably 2 to 10° C./min, and even more preferably 3 to 10° C./min. By setting the temperature rise rate at 1° C./min or more, it is possible to prevent excessive volatilization of the acid or solvent while ensuring productivity, and by setting the temperature rise rate at 12° C./min or less, it is possible to alleviate the residual stress of the cured product.
In addition, in the case of an oven capable of rapid heating, the temperature is increased from the starting temperature to the maximum heating temperature at a rate of preferably 1 to 8° C./sec, more preferably 2 to 7° C./sec, and even more preferably 3 to 6° C./sec.

The temperature at the start of heating is preferably 20°C to 150°C, more preferably 20°C to 130°C, and even more preferably 25°C to 120°C. The temperature at the start of heating refers to the temperature at which the process of heating to the maximum heating temperature begins. For example, when a resin composition is applied to a substrate and then dried, it is the temperature of the film (layer) after this drying, and it is preferable to raise the temperature from a temperature 30 to 200°C lower than the boiling point of the solvent contained in the resin composition.

The heating time (heating time at the maximum heating temperature) is preferably 5 to 360 minutes, more preferably 10 to 300 minutes, and even more preferably 15 to 240 minutes.

In particular, when forming a multi-layer laminate, from the viewpoint of adhesion between layers, the heating temperature is preferably 30° C. or higher, more preferably 80° C. or higher, even more preferably 100° C. or higher, and particularly preferably 120° C. or higher.
The upper limit of the heating temperature is preferably 350° C. or less, more preferably 250° C. or less, and even more preferably 240° C. or less.

Heating may be performed stepwise. For example, a process may be performed in which the temperature is increased from 25°C to 120°C at 3°C/min, held at 120°C for 60 minutes, increased from 120°C to 180°C at 2°C/min, and held at 180°C for 120 minutes. It is also preferable to perform the process while irradiating ultraviolet rays as described in U.S. Pat. No. 9,159,547. Such a pretreatment process can improve the properties of the film. The pretreatment process is preferably performed for a short time of about 10 seconds to 2 hours, more preferably 15 seconds to 30 minutes. The pretreatment process may be performed in two or more steps, for example, a first pretreatment process may be performed in the range of 100 to 150°C, and then a second pretreatment process may be performed in the range of 150 to 200°C.
Furthermore, after heating, the material may be cooled, and in this case, the cooling rate is preferably 1 to 5° C./min.

From the viewpoint of preventing decomposition of the polyimide precursor, the heating step is preferably performed in an atmosphere with a low oxygen concentration by flowing an inert gas such as nitrogen, helium, or argon, or by performing the heating step under reduced pressure, etc. The oxygen concentration is preferably 50 ppm (volume ratio) or less, and more preferably 20 ppm (volume ratio) or less.
The heating means in the heating step is not particularly limited, but examples thereof include a hot plate, an infrared oven, an electric heating oven, a hot air oven, an infrared oven, etc. In particular, for example, an oven with a decompression function can be used. The heating method in the oven is not particularly limited, and may be an electric heating type, a hot air type, an infrared type, etc.

<Condition 1 and Condition 2>
The method for producing a cured product of the present invention satisfies at least one of the following conditions 1 and 2.
Condition 1: The resin composition further contains a compound A having at least one bond selected from a urethane bond and a urea bond, and at least one functional group selected from a tert-butyl group, a hydroxyl group, and a group containing an ethylenically unsaturated group bond.
Condition 2: The method includes a step of contacting the resin layer with a treatment liquid containing the compound A prior to the depressurization step.
Here, from the viewpoints of ease of adjusting the content of compound A, ease of achieving a nearly uniform distribution of compound A in the resin layer, and the like, it is preferable that the method for producing a cured product of the present invention satisfies condition 1.
In addition, from the viewpoint of being able to use a resin composition that does not contain compound A, it is preferable that the method for producing a cured product of the present invention satisfies condition 2.

When the method for producing a cured product of the present invention satisfies condition 1, it is preferable to use a resin composition further containing compound A as the resin composition described below.

In addition, when the method for producing a cured product of the present invention satisfies the above condition 2, it is also preferable that the treatment liquid containing the compound A is any one of a developer, a rinse liquid, and a contact treatment liquid in the development step described below. In addition, the resin layer can be contacted with the contact treatment liquid described below without carrying out the exposure step and development step described below.

<Resin Layer>
The resin layer is a layer formed from a resin composition containing a polyimide precursor and a solvent. When the method for producing a cured product of the present invention satisfies the above-mentioned condition 1, the resin layer further contains compound A.
The components contained in the resin composition and the resin layer will be described in detail below.
The resin layer is preferably formed by applying a resin composition to a substrate and drying it as necessary.
Specifically, the method for producing a cured product of the present invention preferably includes a film-forming step, and more preferably includes a film-forming step and a drying step.

<Film formation process>
The method for producing a cured product of the present invention preferably includes a film formation step of applying the resin composition onto a substrate to form a film.

〔Base material〕
The type of substrate can be appropriately determined according to the application, and is not particularly limited. Examples of substrates include semiconductor-prepared substrates such as silicon, silicon nitride, polysilicon, silicon oxide, and amorphous silicon, quartz, glass, optical films, ceramic materials, vapor deposition films, magnetic films, reflective films, metal substrates such as Ni, Cu, Cr, and Fe (for example, substrates formed from metals and substrates in which a metal layer is formed by plating, vapor deposition, etc.), paper, SOG (Spin On Glass), TFT (thin film transistor) array substrates, mold substrates, and electrode plates of plasma display panels (PDPs). The substrate is preferably a semiconductor-prepared substrate, more preferably a silicon substrate, a Cu substrate, or a mold substrate.
These substrates may have a layer such as an adhesion layer made of hexamethyldisilazane (HMDS) or an oxide layer provided on the surface.
The shape of the substrate is not particularly limited, and may be circular or rectangular.
The size of the substrate is preferably, for example, a diameter of 100 to 450 mm, more preferably 200 to 450 mm, if it is circular, and preferably, a short side length of 100 to 1000 mm, more preferably 200 to 700 mm, if it is rectangular.
As the substrate, for example, a plate-shaped substrate, preferably a panel-shaped substrate (substrate) is used.

When a film is formed by applying a resin composition to the surface of a resin layer (e.g., a layer made of a cured material) or to the surface of a metal layer, the resin layer or metal layer serves as the substrate.

The resin composition is preferably applied to a substrate by coating.
Specific examples of the means to be applied include dip coating, air knife coating, curtain coating, wire bar coating, gravure coating, extrusion coating, spray coating, spin coating, slit coating, and inkjet methods. From the viewpoint of uniformity of the thickness of the film, spin coating, slit coating, spray coating, or inkjet methods are preferred, and from the viewpoint of uniformity of the thickness of the film and productivity, spin coating and slit coating are more preferred. A film of a desired thickness can be obtained by adjusting the solid content concentration and coating conditions of the resin composition according to the means to be applied. In addition, the coating method can be appropriately selected depending on the shape of the substrate, and if the substrate is a circular substrate such as a wafer, spin coating, spray coating, inkjet, etc. are preferred, and if the substrate is a rectangular substrate, slit coating, spray coating, inkjet, etc. are preferred. In the case of the spin coating method, for example, it can be applied for about 10 seconds to 3 minutes at a rotation speed of 500 to 3,500 rpm.
Alternatively, a coating film formed by applying the coating material to a temporary support in advance using the above-mentioned application method may be transferred onto the substrate.
As for the transfer method, the production methods described in paragraphs 0023 and 0036 to 0051 of JP-A No. 2006-023696 and paragraphs 0096 to 0108 of JP-A No. 2006-047592 can be suitably used.
Also, a process for removing excess film from the edge of the substrate may be performed, such as edge bead rinse (EBR) and back rinse.
A pre-wetting step may be employed in which various solvents are applied to the substrate before the resin composition is applied to the substrate to improve the wettability of the substrate, and then the resin composition is applied.

<Drying process>
After the film-forming step (layer-forming step), the above-mentioned film may be subjected to a step of drying the formed film (layer) (drying step) in order to remove the solvent.
That is, the method for producing a cured product of the present invention may include a drying step of drying the film formed in the film forming step.
The drying step is preferably carried out after the film-forming step and before the decompression step.
The drying temperature of the film in the drying step is preferably 50 to 150° C., more preferably 70 to 130° C., and even more preferably 90 to 110° C. Drying may be performed under reduced pressure. The drying time is, for example, 30 seconds to 20 minutes, preferably 1 to 10 minutes, and more preferably 2 to 7 minutes.
The drying step and the decompression step may be carried out as a step of heating and drying under the above-mentioned temperature conditions at a pressure lower than 101,325 Pa.
It is also preferable not to apply a reduced pressure in the drying step.

It is also preferable to further include, prior to the decompression step, a step of exposing a photosensitive resin layer formed from the resin composition further containing a photopolymerization initiator, and a step of developing the exposed photosensitive resin layer to obtain the resin layer.
The photosensitive resin layer is preferably, for example, the film formed by the above-mentioned film formation process using a resin composition further containing a photopolymerization initiator, and more preferably the film formed by the above-mentioned film formation process and the above-mentioned drying process using a resin composition further containing a photopolymerization initiator.

<Exposure process>
The photosensitive resin layer is preferably subjected to an exposure step in which the photosensitive resin layer is selectively exposed to light.
The method for producing a cured product may include an exposure step of selectively exposing the film (photosensitive resin layer) formed in the film formation step.
Selective exposure means that a part of the photosensitive resin layer is exposed to light, and by selective exposure, an exposed area (exposed portion) and an unexposed area (unexposed portion) are formed in the photosensitive resin layer.
The amount of exposure light is not particularly limited as long as it can cure the resin composition, but is preferably 50 to 10,000 mJ/cm ² , and more preferably 200 to 8,000 mJ/cm ² , calculated as exposure energy at a wavelength of 365 nm.

The exposure wavelength can be appropriately set in the range of 190 to 1,000 nm, with 240 to 550 nm being preferred.

In terms of the light source, the exposure wavelength may be, in particular, (1) semiconductor laser (wavelength 830 nm, 532 nm, 488 nm, 405 nm, 375 nm, 355 nm, etc.), (2) metal halide lamp, (3) high pressure mercury lamp, g-line (wavelength 436 nm), h-line (wavelength 405 nm), i-line (wavelength 365 nm), broad (three wavelengths of g, h, i-line), (4) excimer laser, KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), _F2 excimer laser (wavelength 157 nm), (5) extreme ultraviolet light; EUV (wavelength 13.6 nm), (6) electron beam, (7) second harmonic 532 nm, third harmonic 355 nm, etc. of YAG laser. For the resin composition, exposure by a high pressure mercury lamp is particularly preferred, and exposure by i-line is more preferred from the viewpoint of exposure sensitivity.
The exposure method is not particularly limited as long as it is a method that exposes at least a part of the photosensitive resin layer, and examples of the exposure method include exposure using a photomask and exposure by a laser direct imaging method.

<Post-exposure baking process>
The photosensitive resin layer may be subjected to a step of heating after exposure (post-exposure heating step).
That is, the method for producing a cured product of the present invention may include a post-exposure baking step of heating the photosensitive resin layer exposed in the exposure step.
The post-exposure baking step can be carried out after the exposure step and before the development step.
The heating temperature in the post-exposure baking step is preferably from 50°C to 140°C, and more preferably from 60°C to 120°C.
The heating time in the post-exposure baking step is preferably from 30 seconds to 300 minutes, and more preferably from 1 minute to 10 minutes.
The heating rate in the post-exposure heating step is preferably from 1 to 12° C./min, more preferably from 2 to 10° C./min, and even more preferably from 3 to 10° C./min, from the temperature at the start of heating to the maximum heating temperature.
The rate of temperature rise may be appropriately changed during heating.
The heating means in the post-exposure baking step is not particularly limited, and known hot plates, ovens, infrared heaters, etc. can be used.
It is also preferable that the heating be performed in an atmosphere of low oxygen concentration by flowing an inert gas such as nitrogen, helium, or argon.

<Developing process>
The photosensitive resin layer after exposure may be subjected to a development step in which the layer is developed with a developer to form a pattern.
That is, the method for producing a cured product of the present invention may include a development step in which the photosensitive resin layer exposed in the exposure step is developed with a developer to form a pattern.
By carrying out development, one of the exposed and unexposed areas of the photosensitive resin layer is removed to form a pattern.
Here, development in which the non-exposed portion of the photosensitive resin layer is removed by the developing process is called negative development, and development in which the exposed portion of the photosensitive resin layer is removed by the developing process is called positive development.

[Developer]
The developer used in the development step may be an aqueous alkaline solution or a developer containing an organic solvent.

When the developer is an alkaline aqueous solution, examples of basic compounds that the alkaline aqueous solution may contain include inorganic alkalis, primary amines, secondary amines, tertiary amines, and quaternary ammonium salts. Preferred are TMAH (tetramethylammonium hydroxide), potassium hydroxide, sodium carbonate, sodium hydroxide, sodium silicate, sodium metasilicate, ammonia, ethylamine, n-propylamine, diethylamine, di-n-butylamine, triethylamine, methyldiethylamine, dimethylethanolamine, triethanolamine, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, ethyltrimethylammonium hydroxide, butyltrimethylammonium hydroxide, methyltriamylammonium hydroxide, dibutyldipentylammonium hydroxide, dimethylbis(2-hydroxyethyl)ammonium hydroxide, trimethylphenylammonium hydroxide, trimethylbenzylammonium hydroxide, triethylbenzylammonium hydroxide, pyrrole, and piperidine, and more preferably TMAH. The content of the basic compound in the developer is preferably 0.01 to 10% by mass, more preferably 0.1 to 5% by mass, and even more preferably 0.3 to 3% by mass, based on the total mass of the developer.

When the developer contains an organic solvent, the compounds described in paragraph 0387 of WO 2021/112189 can be used as the organic solvent. The contents of this specification are incorporated herein. In addition, examples of alcohols that are suitable include methanol, ethanol, propanol, isopropanol, butanol, pentanol, octanol, diethylene glycol, propylene glycol, methyl isobutyl carbinol, and triethylene glycol, and examples of amides that are suitable include N-methylpyrrolidone, N-ethylpyrrolidone, and dimethylformamide.

When the developer contains an organic solvent, the organic solvent may be used alone or in combination of two or more. In the present invention, a developer containing at least one selected from the group consisting of cyclopentanone, γ-butyrolactone, dimethylsulfoxide, N-methyl-2-pyrrolidone, and cyclohexanone is particularly preferred, a developer containing at least one selected from the group consisting of cyclopentanone, γ-butyrolactone, and dimethylsulfoxide is more preferred, and a developer containing cyclopentanone is particularly preferred.

When the developer contains an organic solvent, the content of the organic solvent relative to the total mass of the developer is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 80% by mass or more, and particularly preferably 90% by mass or more. The content may be 100% by mass.

The developer may contain compound A. According to such an embodiment, the method for producing a cured product of the present invention can satisfy the above-mentioned condition 2.
The details of compound A will be described later.
The content of compound A in the developer is not particularly limited, but is preferably from 1 to 20% by mass, more preferably from 2 to 15% by mass, and even more preferably from 3 to 8% by mass, based on the total mass of the developer.
The developer may contain one type of compound A alone or two or more types in combination. When two or more types are used in combination, the total amount thereof is preferably within the above range.

When the developer contains an organic solvent, the developer may further contain at least one of a basic compound and a base generator. When at least one of the basic compound and the base generator in the developer permeates the pattern, the performance of the pattern, such as the breaking elongation, may be improved.

As the basic compound, from the viewpoint of reliability when it remains in the cured film (adhesion to a substrate when the cured product is further heated), an organic base is preferred.
As the basic compound, a basic compound having an amino group is preferable, and a primary amine, a secondary amine, a tertiary amine, an ammonium salt, a tertiary amide, or the like is preferable. In order to promote the imidization reaction, a primary amine, a secondary amine, a tertiary amine, or an ammonium salt is preferable, a secondary amine, a tertiary amine, or an ammonium salt is more preferable, a secondary amine or a tertiary amine is even more preferable, and a tertiary amine is particularly preferable.
From the viewpoint of the mechanical properties (elongation at break) of the cured product, it is preferable for the basic compound to be one that is unlikely to remain in the cured film (obtained cured product), and from the viewpoint of promoting cyclization, it is preferable for the basic compound to be one that is unlikely to decrease in the amount remaining before heating due to vaporization, etc.
Therefore, the boiling point of the basic compound is preferably 30°C to 350°C, more preferably 80°C to 270°C, and even more preferably 100°C to 230°C at normal pressure (101,325 Pa).
The boiling point of the basic compound is preferably higher than the temperature obtained by subtracting 20° C. from the boiling point of the organic solvent contained in the developer, and more preferably higher than the boiling point of the organic solvent contained in the developer.
For example, when the boiling point of the organic solvent is 100° C., the basic compound used preferably has a boiling point of 80° C. or higher, and more preferably has a boiling point of 100° C. or higher.
The developer may contain only one kind of basic compound, or may contain two or more kinds of basic compounds.

Specific examples of basic compounds include ethanolamine, diethanolamine, triethanolamine, ethylamine, diethylamine, triethylamine, hexylamine, dodecylamine, cyclohexylamine, cyclohexylmethylamine, cyclohexyldimethylamine, aniline, N-methylaniline, N,N-dimethylaniline, diphenylamine, pyridine, butylamine, isobutylamine, dibutylamine, tributylamine, dicyclohexylamine, DBU (diazabicycloundecene), DABCO (1,4-diazabicyclo[2.2.2]octane), N,N-diisopropylethylamine, tetramethylammonium hydroxide, tetrabutylammonium hydroxide, ethylenediamine, butanediamine, 1,5-diamino Examples include pentane, N-methylhexylamine, N-methyldicyclohexylamine, trioctylamine, N-ethylethylenediamine, N,N-diethylethylenediamine, N,N,N',N'-tetrabutyl-1,6-hexanediamine, spermidine, diaminocyclohexane, bis(2-methoxyethyl)amine, piperidine, methylpiperidine, dimethylpiperidine, piperazine, tropane, N-phenylbenzylamine, 1,2-dianilinoethane, 2-aminoethanol, toluidine, aminophenol, hexylaniline, phenylenediamine, phenylethylamine, dibenzylamine, pyrrole, N-methylpyrrole, N,N,N,N-tetramethylethylenediamine, and N,N,N,N-tetramethyl-1,3-propanediamine.

The preferred embodiment of the base generator is the same as the preferred embodiment of the base generator contained in the composition described above. In particular, it is preferred that the base generator is a thermal base generator.

When the developer contains at least one of a basic compound and a base generator, the content of the basic compound or the base generator is preferably 10% by mass or less, more preferably 5% by mass or less, based on the total mass of the developer. The lower limit of the content is not particularly limited, but is preferably, for example, 0.1% by mass or more.
When the basic compound or base generator is a solid in the environment in which the developer is used, the content of the basic compound or base generator is preferably 70 to 100% by mass based on the total solid content of the developer.
The developer may contain at least one of a basic compound and a base generator, or may contain two or more of them. When at least one of a basic compound and a base generator is two or more, the total amount of them is preferably within the above range.

The developer may further comprise other components.
Examples of other components include known surfactants and known defoamers.

[Method of Supplying Developer]
The method of supplying the developer is not particularly limited as long as the desired pattern can be formed, and includes a method of immersing a substrate on which a photosensitive resin layer is formed in the developer, a paddle development method in which the developer is supplied to the photosensitive resin layer formed on the substrate using a nozzle, and a method of continuously supplying the developer. The type of nozzle is not particularly limited, and examples thereof include a straight nozzle, a shower nozzle, and a spray nozzle.
From the viewpoints of the permeability of the developer, the removability of non-image areas, and production efficiency, a method of supplying the developer through a straight nozzle or a method of continuously supplying the developer through a spray nozzle is preferred, and from the viewpoint of the permeability of the developer into the image areas, a method of supplying the developer through a spray nozzle is more preferred.
Alternatively, a process may be adopted in which the developer is continuously supplied through a straight nozzle, the substrate is spun to remove the developer from the substrate, and after spin drying, the developer is continuously supplied again through a straight nozzle, and the substrate is spun to remove the developer from the substrate. This process may be repeated multiple times.
Methods of supplying the developer in the development step include a step in which the developer is continuously supplied to the substrate, a step in which the developer is kept substantially stationary on the substrate, a step in which the developer is vibrated by ultrasonic waves or the like on the substrate, and a combination of these steps.

The development time is preferably 10 seconds to 10 minutes, and more preferably 20 seconds to 5 minutes. The temperature of the developer during development is not particularly specified, but is preferably 10 to 45°C, and more preferably 18°C to 30°C.

In the development process, after treatment with the developer, the pattern may be washed (rinsed) with a rinse solution. Also, a method may be adopted in which a rinse solution is supplied before the developer in contact with the pattern has completely dried.

[Rinse solution]
When the developer is an alkaline aqueous solution, the rinse liquid may be, for example, water. When the developer is an organic solvent-containing developer, the rinse liquid may be, for example, a solvent different from the solvent contained in the developer (for example, water, an organic solvent different from the organic solvent contained in the developer).

When the rinsing liquid contains an organic solvent, examples of the organic solvent include the same organic solvents as those exemplified when the developer contains an organic solvent.
The organic solvent contained in the rinse liquid is preferably different from the organic solvent contained in the developer, and more preferably has a lower solubility for the pattern than the organic solvent contained in the developer.

When the rinse solution contains an organic solvent, the organic solvent may be used alone or in combination of two or more. The organic solvent is preferably cyclopentanone, γ-butyrolactone, dimethylsulfoxide, N-methylpyrrolidone, cyclohexanone, PGMEA, or PGME, more preferably cyclopentanone, γ-butyrolactone, dimethylsulfoxide, PGMEA, or PGME, and even more preferably cyclohexanone or PGMEA.

When the rinse solution contains an organic solvent, the organic solvent preferably accounts for 50% by mass or more, more preferably 70% by mass or more, and even more preferably 90% by mass or more, based on the total mass of the rinse solution. Furthermore, the organic solvent may account for 100% by mass, based on the total mass of the rinse solution.

The rinse liquid may contain compound A. According to such an embodiment, the method for producing a cured product of the present invention can satisfy the above-mentioned condition 2.
The content of compound A in the rinse solution is not particularly limited, but is preferably 1 to 20 mass %, more preferably 2 to 15 mass %, and even more preferably 3 to 8 mass %, based on the total mass of the rinse solution.
The rinse may contain one type of compound A alone or two or more types in combination. When two or more types are used in combination, it is preferable that the total amount of these is within the above range.

The rinse liquid may contain at least one of a basic compound and a base generator.
Although not particularly limited, when the developer contains an organic solvent, an embodiment in which the rinsing liquid contains an organic solvent and at least one of a basic compound and a base generator is also one of the preferred embodiments of the present invention.
Examples of the basic compound and base generator contained in the rinse solution include the compounds exemplified as the basic compound and base generator that may be contained in the above-mentioned developer containing an organic solvent, and preferred embodiments thereof are also the same.
The basic compound and base generator contained in the rinse solution may be selected in consideration of the solubility in the solvent in the rinse solution.

When the rinse solution contains at least one of a basic compound and a base generator, the content of the basic compound or the base generator is preferably 10% by mass or less, more preferably 5% by mass or less, based on the total mass of the rinse solution. The lower limit of the content is not particularly limited, but is preferably, for example, 0.1% by mass or more.
When the basic compound or base generator is a solid in the environment in which the rinse liquid is used, the content of the basic compound or base generator is also preferably 70 to 100 mass % based on the total solid content of the rinse liquid.
When the rinse solution contains at least one of a basic compound and a base generator, the rinse solution may contain only one kind of at least one of the basic compound and the base generator, or may contain two or more kinds. When at least one of the basic compound and the base generator contains two or more kinds, the total amount thereof is preferably within the above range.

The rinse solution may further contain other ingredients.
Examples of other components include known surfactants and known defoamers.

[Method of Supplying Rinse Liquid]
The method of supplying the rinse liquid is not particularly limited as long as it can form a desired pattern, and examples of the method include a method of immersing the substrate in the rinse liquid, a method of supplying the rinse liquid to the substrate by puddling, a method of supplying the rinse liquid to the substrate by showering, and a method of continuously supplying the rinse liquid onto the substrate by means of a straight nozzle or the like.
From the viewpoints of the permeability of the rinse liquid, the removability of non-image areas, and production efficiency, the rinse liquid may be supplied using a shower nozzle, a straight nozzle, a spray nozzle, etc., and the method of continuously supplying the rinse liquid using a spray nozzle is preferred, while from the viewpoint of the permeability of the rinse liquid into the image areas, the method of supplying the rinse liquid using a spray nozzle is more preferred. There are no particular limitations on the type of nozzle, and examples include a straight nozzle, a shower nozzle, a spray nozzle, etc.
That is, the rinsing step is preferably a step of supplying a rinsing liquid to the exposed photosensitive resin layer through a straight nozzle or continuously supplying the rinsing liquid to the exposed photosensitive resin layer, and more preferably a step of supplying the rinsing liquid through a spray nozzle.
The method of supplying the rinsing liquid in the rinsing step may include a step of continuously supplying the rinsing liquid to the substrate, a step of keeping the rinsing liquid in a substantially stationary state on the substrate, a step of vibrating the rinsing liquid on the substrate by ultrasonic waves or the like, and a combination of these steps.

The rinsing time is preferably 10 seconds to 10 minutes, and more preferably 20 seconds to 5 minutes. The temperature of the rinsing liquid during rinsing is not particularly specified, but is preferably 10 to 45°C, and more preferably 18°C to 30°C.

The developing step may include a step of contacting the pattern with a treatment liquid for contact after the treatment with the developer or after the cleaning of the pattern with a rinse liquid. Also, a method of supplying the treatment liquid for contact before the developer or rinse liquid in contact with the pattern is completely dried may be employed.
The contact treatment liquid may be a contact treatment liquid containing at least one of water and an organic solvent, and compound A. According to such an embodiment, the method for producing a cured product of the present invention can satisfy the above-mentioned condition 2.
The content of compound A in the contact treatment liquid is not particularly limited, but is preferably 1 to 20 mass %, more preferably 2 to 15 mass %, and even more preferably 3 to 8 mass %, based on the total mass of the contact treatment liquid.
The contact treatment liquid may contain one type of compound A alone or two or more types in combination. When two or more types are used in combination, the total amount thereof is preferably within the above range.

The contact treatment liquid may be a contact treatment liquid containing at least one of water and an organic solvent, and at least one of a basic compound and a base generator.
Preferred aspects of the organic solvent, and at least one of the basic compound and the base generator are the same as the preferred aspects of the organic solvent, and at least one of the basic compound and the base generator used in the above-mentioned rinse solution.
The contact treatment liquid can be supplied to the pattern in the same manner as the above-mentioned method for supplying the rinsing liquid, and the preferred embodiments are also the same.

The content of the basic compound or base generator in the contact treatment liquid is preferably 10% by mass or less, more preferably 5% by mass or less, based on the total mass of the contact treatment liquid. The lower limit of the content is not particularly limited, but is preferably, for example, 0.1% by mass or more.
In addition, when the basic compound or the base generator is a solid in the environment in which the contact treatment liquid is used, the content of the basic compound or the base generator is also preferably 70 to 100 mass % based on the total solid content of the contact treatment liquid.
When the contact treatment liquid contains at least one of a basic compound and a base generator, the contact treatment liquid may contain only one kind of at least one of a basic compound and a base generator, or may contain two or more kinds. When at least one of a basic compound and a base generator contains two or more kinds, the total of them is preferably in the above range.

<Metal Layer Forming Process>
The method for producing a cured product of the present invention preferably includes a metal layer forming step of forming a metal layer on the cured resin layer obtained by the heating step.

The metal layer can be made of any existing metal type without any particular limitations, and examples include copper, aluminum, nickel, vanadium, titanium, chromium, cobalt, gold, tungsten, tin, silver, and alloys containing these metals, with copper and aluminum being more preferred, and copper being even more preferred.

The method for forming the metal layer is not particularly limited, and existing methods can be applied. For example, the methods described in JP 2007-157879 A, JP 2001-521288 A, JP 2004-214501 A, JP 2004-101850 A, U.S. Patent No. 7,888,181 B2, and U.S. Patent No. 9,177,926 B2 can be used. For example, photolithography, PVD (physical vapor deposition), CVD (chemical vapor deposition), lift-off, electrolytic plating, electroless plating, etching, printing, and combinations of these methods are possible. More specifically, there are patterning methods that combine sputtering, photolithography, and etching, and patterning methods that combine photolithography and electrolytic plating. A preferred embodiment of plating is electrolytic plating using copper sulfate or copper cyanide plating solution.

The thickness of the metal layer at its thickest point is preferably 0.01 to 50 μm, and more preferably 1 to 10 μm.

<Applications>
Examples of the field of application of the method for producing the cured product of the present invention or the cured product include insulating films for electronic devices, interlayer insulating films for rewiring layers, stress buffer films, etc. Other examples include etching patterns of sealing films, substrate materials (base films and coverlays for flexible printed circuit boards, interlayer insulating films), or insulating films for mounting applications such as those described above. For these applications, reference can be made to, for example, Science & Technology Co., Ltd. "High-performance and Applied Technology of Polyimides" April 2008, supervised by Masaaki Kakimoto, CMC Technical Library "Basics and Development of Polyimide Materials" published in November 2011, and Japan Polyimide and Aromatic Polymer Research Association/editor "Latest Polyimides Basics and Applications" NTS, August 2010.

The method for producing a cured product of the present invention, or the cured product obtained by the method for producing a cured product of the present invention, can also be used for producing printing plates such as offset printing plates or screen printing plates, for etching molded parts, and for producing protective lacquers and dielectric layers in electronics, especially microelectronics.

(Laminate and method for manufacturing laminate)
The laminate refers to a structure having a plurality of layers each made of a cured product obtained by the method for producing a cured product of the present invention.
The laminate is a laminate including two or more layers made of a cured product, and may be a laminate including three or more layers.
Of the two or more layers made of the cured product contained in the laminate, at least one is a layer made of a cured product obtained by the method for producing a cured product of the present invention, and from the viewpoint of suppressing shrinkage of the cured product or deformation of the cured product associated with the shrinkage, it is also preferable that all of the layers made of the cured product contained in the laminate are layers made of a cured product obtained by the method for producing a cured product of the present invention.

In other words, the method for producing the laminate of the present invention preferably includes the method for producing the cured product of the present invention, and more preferably includes repeating the method for producing the cured product of the present invention multiple times.

The laminate obtained by the method for producing a laminate of the present invention preferably includes two or more layers made of a cured product, and includes a metal layer between any two of the layers made of the cured product. The metal layer is preferably formed by the metal layer forming step.
That is, the method for producing a laminate of the present invention preferably further includes a metal layer forming step of forming a metal layer on a layer made of a cured product between the steps for producing a cured product which are performed multiple times. A preferred embodiment of the metal layer forming step is as described above.
As the laminate, for example, a laminate including at least a layer structure in which three layers, a layer made of a first cured product, a metal layer, and a layer made of a second cured product, are laminated in this order, can be mentioned as a preferred example.
The layer made of the first cured product and the layer made of the second cured product are preferably layers made of a cured product obtained by the method for producing a cured product of the present invention. The resin composition used to form the layer made of the first cured product and the resin composition used to form the layer made of the second cured product may be compositions having the same composition or different compositions. The metal layer in the laminate obtained by the method for producing a laminate of the present invention is preferably used as metal wiring such as a rewiring layer.

<Lamination process>
The method for producing the laminate of the present invention preferably includes a lamination step.
The lamination process is a series of processes including (a) a film formation process (layer formation process), (b) an exposure process, (c) a development process, (d) a pressure reduction process and a heating process, which are carried out again on the surface of the pattern (resin layer) or the metal layer in this order. However, the (a) film formation process and the (d) pressure reduction process and heating process may be repeated. In addition, after at least one of the (d) heating process and the post-development exposure process, the (e) metal layer formation process may be included. It goes without saying that the lamination process may further include the above-mentioned drying process and the like as appropriate.

If a further lamination step is performed after the lamination step, a surface activation treatment step may be performed after the exposure step, the heating step, or the metal layer formation step. An example of the surface activation treatment is a plasma treatment. Details of the surface activation treatment will be described later.

The lamination step is preferably carried out 2 to 20 times, and more preferably 2 to 9 times.
For example, a structure of 2 to 20 resin layers, such as resin layer/metal layer/resin layer/metal layer/resin layer/metal layer, is preferred, and a structure of 2 to 9 resin layers is more preferred.
The layers may be the same or different in composition, shape, film thickness, etc.

In the present invention, a particularly preferred embodiment is one in which, after providing a metal layer, a cured product (resin layer) of the resin composition is further formed so as to cover the metal layer. Specifically, the following steps are repeated in this order: (a) film formation step, (b) exposure step, (c) development step, (d) pressure reduction step and heating step, and (e) metal layer formation step; or the following steps are repeated in this order: (a) film formation step, (d) pressure reduction step and heating step, and (e) metal layer formation step. By alternately performing the lamination step of laminating resin composition layers (resin layers) and the metal layer formation step, the resin composition layers (resin layers) and the metal layer can be laminated alternately.

(Surface activation treatment process)
The method for producing a laminate of the present invention preferably includes a surface activation treatment step of subjecting at least a portion of the metal layer and the resin composition layer to a surface activation treatment.
The surface activation treatment step is usually carried out after the metal layer formation step, but the resin composition layer may be subjected to a surface activation treatment step after the above-mentioned development step (preferably after the heating step) and then the metal layer formation step may be carried out.
The surface activation treatment may be performed on at least a part of the metal layer, or on at least a part of the resin composition layer after exposure, or on at least a part of both the metal layer and the resin composition layer after exposure. The surface activation treatment is preferably performed on at least a part of the metal layer, and it is preferable to perform the surface activation treatment on a part or all of the area of the metal layer on which the resin composition layer is formed on the surface. In this way, by performing the surface activation treatment on the surface of the metal layer, the adhesion with the resin composition layer (film) provided on the surface can be improved.
It is preferable to perform the surface activation treatment on a part or the whole of the resin composition layer (resin layer) after exposure. In this way, by performing the surface activation treatment on the surface of the resin composition layer, it is possible to improve the adhesion with the metal layer or the resin layer provided on the surface that has been surface-activated. In particular, when performing negative development, etc., when the resin composition layer is cured, it is less likely to be damaged by the surface treatment, and the adhesion is likely to be improved.
The surface activation treatment can be carried out, for example, by the method described in paragraph 0415 of WO 2021/112189, the contents of which are incorporated herein by reference.

(Semiconductor device and its manufacturing method)
The present invention also discloses a semiconductor device including a cured product obtained by the method for producing a cured product of the present invention, or a laminate obtained by the method for producing a laminate of the present invention.
The present invention also discloses a method for producing a semiconductor device, which includes the method for producing the cured product or the method for producing the laminate of the present invention.
As specific examples of semiconductor devices in which the resin composition is used to form an interlayer insulating film for a rewiring layer, the descriptions in paragraphs 0213 to 0218 and FIG. 1 of JP-A-2016-027357 can be referred to, and the contents of these are incorporated herein by reference.

The components contained in the resin composition used to form the resin layer in the method for producing a cured product of the present invention will be described in detail below.
The components contained in the resin layer are the same as those contained in the resin composition, but when the method for producing a cured product of the present invention includes the above-mentioned exposure step, the polymerizable compound, the compound A having a radical polymerizable group, etc. may be polymerized in the resin layer. Also, the photopolymerization initiator, etc. may be decomposed by exposure to light.
Furthermore, when the method for producing a cured product of the present invention includes the above-mentioned drying step, the solvent may volatilize.
The content of the solvent in the resin layer immediately before being subjected to the decompression step is preferably 0.001 to 10% by mass, and more preferably 0.01 to 5% by mass, based on the total mass of the resin layer.
The content of the components other than the solvent in the resin layer is obtained by replacing the meaning of "relative to the total solid content of the resin composition" below with "relative to the total solid content of the resin layer." However, as described above, in the resin layer, the structure of each component may change due to polymerization, decomposition due to exposure, etc.
In addition, since a decompression process is performed, it is preferable that each component has a large molecular weight, that the final molecular weight of which increases through polymerization or the like, and that each component has a high affinity and is easily compatible with the membrane so that each component is likely to remain in the final cured product.
In addition, since it is preferable that the solvent or the decomposition product of the photoradical polymerization initiator is evaporated by the decompression step, it is preferable to select a solvent having a small molecular weight and a low boiling point.

<Polyimide precursor>
The resin composition includes a polyimide precursor.
The polyimide precursor preferably has a polymerizable group, and more preferably contains a radically polymerizable group.
When the polyimide precursor has a radical polymerizable group, the resin composition preferably contains a radical polymerization initiator, more preferably contains a radical polymerization initiator and a radical crosslinking agent. If necessary, the resin composition may further contain a sensitizer. For example, a negative photosensitive film is formed from such a resin composition.
The polyimide precursor may also have a polarity conversion group such as an acid-decomposable group.
When the polyimide precursor has an acid-decomposable group, the resin composition preferably contains a photoacid generator. From such a resin composition, for example, a chemically amplified positive or negative photosensitive film is formed.

[Polyimide precursor]
The polyimide precursor used in the present invention is not particularly limited in type, but preferably contains a repeating unit represented by the following formula (2).

In formula (2), ^A1 and ^A2 each independently represent an oxygen atom or ^-NRz- , ^R111 represents a divalent organic group, ^R115 represents a tetravalent organic group, ^R113 and ^R114 each independently represent a hydrogen atom or a monovalent organic group, and ^Rz represents a hydrogen atom or a monovalent organic group.

In formula (2), A ¹ and A ² each independently represent an oxygen atom or —NR ^z —, and preferably an oxygen atom.
^Rz represents a hydrogen atom or a monovalent organic group, and is preferably a hydrogen atom.
R ¹¹¹ in formula (2) represents a divalent organic group. Examples of the divalent organic group include a linear or branched aliphatic group, a cyclic aliphatic group, and a group containing an aromatic group. A linear or branched aliphatic group having 2 to 20 carbon atoms, a cyclic aliphatic group having 3 to 20 carbon atoms, an aromatic group having 3 to 20 carbon atoms, or a group consisting of a combination thereof is preferred, and a group containing an aromatic group having 6 to 20 carbon atoms is more preferred. The linear or branched aliphatic group may have a hydrocarbon group in the chain substituted with a group containing a heteroatom, and the cyclic aliphatic group and aromatic group may have a hydrocarbon group in the ring substituted with a group containing a heteroatom. Examples of R ¹¹¹ in formula (2) include groups represented by -Ar- and -Ar-L-Ar-, and a group represented by -Ar-L-Ar- is preferred. Here, each Ar is independently an aromatic group, and L is a single bond, an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, -O-, -CO-, -S-, -SO ₂ - or -NHCO-, or a group consisting of a combination of two or more of the above. The preferred ranges of these are as described above.

R ¹¹¹ is preferably derived from a diamine. Examples of the diamine used in the production of the polyimide precursor include linear or branched aliphatic, cyclic aliphatic or aromatic diamines. Only one type of diamine may be used, or two or more types may be used.
Specifically, R ¹¹¹ is preferably a diamine containing a linear or branched aliphatic group having 2 to 20 carbon atoms, a cyclic aliphatic group having 3 to 20 carbon atoms, an aromatic group having 3 to 20 carbon atoms, or a group consisting of a combination thereof, and more preferably a diamine containing an aromatic group having 6 to 20 carbon atoms. The linear or branched aliphatic group may have a hydrocarbon group in the chain substituted with a group containing a hetero atom, and the cyclic aliphatic group and aromatic group may have a hydrocarbon group in the ring substituted with a group containing a hetero atom. Examples of groups containing an aromatic group include the following.

In the formula, A represents a single bond or a divalent linking group, and is preferably a single bond, an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, -O-, -C(=O)-, -S-, -SO ₂ -, -NHCO-, or a group selected from combinations thereof, more preferably a single bond, an alkylene group having 1 to 3 carbon atoms which may be substituted with a fluorine atom, -O-, -C(=O)-, -S-, or -SO ₂ -, and further preferably -CH ₂ -, -O-, -S-, -SO ₂ -, -C(CF ₃ ) ₂ -, or -C(CH ₃ ) ₂ -.
In the formula, * represents a bonding site with other structures.

Specific examples of diamines include 1,2-diaminoethane, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, and 1,6-diaminohexane;
1,2- or 1,3-diaminocyclopentane, 1,2-, 1,3- or 1,4-diaminocyclohexane, 1,2-, 1,3- or 1,4-bis(aminomethyl)cyclohexane, bis-(4-aminocyclohexyl)methane, bis-(3-aminocyclohexyl)methane, 4,4'-diamino-3,3'-dimethylcyclohexylmethane, and isophoronediamine;
m- or p-phenylenediamine, diaminotoluene, 4,4'- or 3,3'-diaminobiphenyl, 4,4'-diaminodiphenyl ether, 3,3-diaminodiphenyl ether, 4,4'- or 3,3'-diaminodiphenylmethane, 4,4'- or 3,3'-diaminodiphenyl sulfone, 4,4'- or 3,3'-diaminodiphenyl sulfide, 4,4'- or 3,3'-diaminobenzophenone, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl phenyl, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis(3-hydroxy-4-aminophenyl)propane, 2,2-bis(3-hydroxy-4-aminophenyl)hexafluoropropane, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-amino-3-hydroxyphenyl)sulfone, 4,4'-diaminoparaterphenyl , 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(2-aminophenoxy)phenyl]sulfone, 1,4-bis(4-aminophenoxy)benzene, 9,10-bis(4-aminophenyl)anthracene, 3,3'-dimethyl-4,4'-diaminodiphenylsulfone, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenyl)benzene, 3,3'-di Ethyl-4,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 4,4'-diaminooctafluorobiphenyl, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 9,9-bis(4-aminophenyl)-10-hydroanthracene, 3,3',4,4'-tetraaminobiphenyl, 3,3',4,4'-tetraaminodiphenyl ether, 1,4-diaminoanthraquinone, 1,5-diaminoanthraquinone, 3,3-dihydro 4,4'-dimethyl-3,3'-diaminodiphenyl sulfone, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 2,4- and 2,5-diaminocumene, 2,5-dimethyl-p-phenylenediamine, acetoguanamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,4,6-trimethyl-m-phenylenediamine, bis(3-aminopropyl)tetramethyldisiloxane, bis(p-aminophenyl)octamethylpentasiloxane , 2,7-diaminofluorene, 2,5-diaminopyridine, 1,2-bis(4-aminophenyl)ethane, diaminobenzanilide, esters of diaminobenzoic acid, 1,5-diaminonaphthalene, diaminobenzotrifluoride, 1,3-bis(4-aminophenyl)hexafluoropropane, 1,4-bis(4-aminophenyl)octafluorobutane, 1,5-bis(4-aminophenyl)decafluoropentane, 1,7-bis(4-aminophenyl)tetradecafluoroheptane, 2,2-bis[4-(3-aminophenoxy)phenyl]hexafluoropropane , 2,2-bis[4-(2-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)-3,5-dimethylphenyl]hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)-3,5-bis(trifluoromethyl)phenyl]hexafluoropropane, p-bis(4-amino-2-trifluoromethylphenoxy)benzene, 4,4'-bis(4-amino-2-trifluoromethylphenoxy)biphenyl, 4,4'-bis(4-amino-3-trifluoromethylphenoxy)biphenyl, 4,4'-bis(4 and at least one diamine selected from 3,3',5,5'-tetramethyl-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl, 2,2',5,5',6,6'-hexafluorotolidine, and 4,4'-diaminoquaterphenyl.

Also preferred are the diamines (DA-1) to (DA-18) described in paragraphs 0030 to 0031 of WO 2017/038598.

Also preferably used are diamines having two or more alkylene glycol units in the main chain, as described in paragraphs 0032 to 0034 of WO 2017/038598.

From the viewpoint of flexibility of the resulting organic film, R ¹¹¹ is preferably represented by -Ar-L-Ar-. Here, each Ar is independently an aromatic group, and L is an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, -O-, -CO-, -S-, -SO ₂ - or -NHCO-, or a group consisting of a combination of two or more of the above. Ar is preferably a phenylene group, and L is preferably an aliphatic hydrocarbon group having 1 or 2 carbon atoms which may be substituted with a fluorine atom, -O-, -CO-, -S- or -SO ₂ -. The aliphatic hydrocarbon group here is preferably an alkylene group.

From the viewpoint of i-line transmittance, R ¹¹¹ is preferably a divalent organic group represented by the following formula (51) or formula (61). In particular, from the viewpoints of i-line transmittance and ease of availability, R 111 is more preferably a divalent organic group represented by formula (61).
Equation (51)

In formula (51), R ⁵⁰ to R ⁵⁷ each independently represent a hydrogen atom, a fluorine atom, or a monovalent organic group, at least one of R ⁵⁰ to R ⁵⁷ represents a fluorine atom, a methyl group, or a trifluoromethyl group, and * each independently represents a bonding site with the nitrogen atom in formula (2).
Examples of the monovalent organic group for R ⁵⁰ to R ⁵⁷ include an unsubstituted alkyl group having 1 to 10 carbon atoms (preferably 1 to 6 carbon atoms) and a fluorinated alkyl group having 1 to 10 carbon atoms (preferably 1 to 6 carbon atoms).

In formula (61), R ⁵⁸ and R ⁵⁹ each independently represent a fluorine atom, a methyl group, or a trifluoromethyl group, and * each independently represents a bonding site to the nitrogen atom in formula (2).
Examples of diamines that give the structure of formula (51) or formula (61) include 2,2'-dimethylbenzidine, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 2,2'-bis(fluoro)-4,4'-diaminobiphenyl, 4,4'-diaminooctafluorobiphenyl, etc. These may be used alone or in combination of two or more.

In formula (2), R ¹¹⁵ represents a tetravalent organic group. As the tetravalent organic group, a tetravalent organic group containing an aromatic ring is preferable, and a group represented by the following formula (5) or formula (6) is more preferable.
In formula (5) or (6), each * independently represents a bonding site to another structure.

In formula (5), R ¹¹² is a single bond or a divalent linking group and is preferably a single bond, or a group selected from an aliphatic hydrocarbon group having 1 to 10 carbon atoms which may be substituted with a fluorine atom, -O-, -CO-, -S-, -SO ₂ -, -NHCO-, and a combination thereof, more preferably a single bond, or an alkylene group having 1 to 3 carbon atoms which may be substituted with a fluorine atom, -O-, -CO-, -S-, and -SO ₂ -, and still more preferably a divalent group selected from the group consisting of -CH ₂ -, -C(CF ₃ ) ₂ -, -C(CH ₃ ) ₂ -, -O-, -CO-, -S-, and -SO ₂ -.

Specific examples of R ¹¹⁵ include tetracarboxylic acid residues remaining after removal of anhydride groups from tetracarboxylic dianhydride. The polyimide precursor may contain only one type of tetracarboxylic dianhydride residue or two or more types of tetracarboxylic dianhydride residues as the structure corresponding to R ¹¹⁵ .
The tetracarboxylic dianhydride is preferably represented by the following formula (O).

In formula (O), R ¹¹⁵ represents a tetravalent organic group. R ¹¹⁵ has the same meaning as R ¹¹⁵ in formula (2), and the preferred range is also the same.

Specific examples of tetracarboxylic dianhydrides include pyromellitic dianhydride (PMDA), 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 3,3',4,4'-diphenyl sulfide tetracarboxylic dianhydride, 3,3',4,4'-diphenyl sulfone tetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenyl methane tetracarboxylic dianhydride, 2 ,2',3,3'-diphenylmethane tetracarboxylic dianhydride, 2,3,3',4'-biphenyl tetracarboxylic dianhydride, 2,3,3',4'-benzophenone tetracarboxylic dianhydride, 4,4'-oxydiphthalic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 1,4,5,7-naphthalene tetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2 ,3-dicarboxyphenyl)propane dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 1,3-diphenylhexafluoropropane-3,3,4,4-tetracarboxylic dianhydride, 1,4,5,6-naphthalene tetracarboxylic dianhydride, 2,2',3,3'-diphenyl tetracarboxylic dianhydride, 3,4,9,10-perylene tetracarboxylic dianhydride, 1,2,4,5-naphthalene tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 1,8,9,10-phenanthrene tetracarboxylic dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1-bis(3,4-dicarboxyphenyl)ethane dianhydride, 1,2,3,4-benzene tetracarboxylic dianhydride, and their alkyl and alkoxy derivatives having 1 to 6 carbon atoms.

Furthermore, tetracarboxylic dianhydrides (DAA-1) to (DAA-5) described in paragraph 0038 of WO 2017/038598 are also preferred examples.

In the formula (2), at least one of R ¹¹¹ and R ¹¹⁵ may have an OH group. More specifically, R ¹¹¹ may be a residue of a bisaminophenol derivative.

R ¹¹³ and R ¹¹⁴ in formula (2) each independently represent a hydrogen atom or a monovalent organic group. The monovalent organic group preferably contains a linear or branched alkyl group, a cyclic alkyl group, an aromatic group, or a polyalkyleneoxy group. In addition, it is preferable that at least one of R ¹¹³ and R ¹¹⁴ contains a polymerizable group, and it is more preferable that both contain a polymerizable group. It is also preferable that at least one of R ¹¹³ and R ¹¹⁴ contains two or more polymerizable groups. The polymerizable group is a group capable of crosslinking by the action of heat, radicals, etc., and is preferably a radical polymerizable group. Specific examples of the polymerizable group include a group having an ethylenically unsaturated bond, an alkoxymethyl group, a hydroxymethyl group, an acyloxymethyl group, an epoxy group, an oxetanyl group, a benzoxazolyl group, a blocked isocyanate group, and an amino group. As the radical polymerizable group of the polyimide precursor, a group having an ethylenically unsaturated bond is preferable.
Examples of the group having an ethylenically unsaturated bond include a vinyl group, an allyl group, an isoallyl group, a 2-methylallyl group, a group having an aromatic ring directly bonded to a vinyl group (for example, a vinylphenyl group), a (meth)acrylamide group, a (meth)acryloyloxy group, and a group represented by the following formula (III), and the group represented by the following formula (III) is preferred.

In formula (III), R ²⁰⁰ represents a hydrogen atom, a methyl group, an ethyl group or a methylol group, and is preferably a hydrogen atom or a methyl group.
In formula (III), * represents a bonding site with another structure.
In formula (III), R ²⁰¹ represents an alkylene group having 2 to 12 carbon atoms, —CH ₂ CH(OH)CH ₂ —, a cycloalkylene group or a polyalkyleneoxy group.
Suitable examples of R ²⁰¹ include alkylene groups such as ethylene group, propylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group, octamethylene group, and dodecamethylene group, 1,2-butanediyl group, 1,3-butanediyl group, -CH ₂ CH(OH)CH ₂ -, and polyalkyleneoxy groups, of which alkylene groups such as ethylene group and propylene group, -CH ₂ CH(OH)CH ₂ -, cyclohexyl group, and polyalkyleneoxy groups are more preferred, and alkylene groups such as ethylene group and propylene group, or polyalkyleneoxy groups are even more preferred.
In the present invention, the polyalkyleneoxy group refers to a group in which two or more alkyleneoxy groups are directly bonded. The alkylene groups in the multiple alkyleneoxy groups contained in the polyalkyleneoxy group may be the same or different.
When the polyalkyleneoxy group contains multiple types of alkyleneoxy groups having different alkylene groups, the arrangement of the alkyleneoxy groups in the polyalkyleneoxy group may be a random arrangement, an arrangement having blocks, or an arrangement having a pattern such as alternating.
The number of carbon atoms in the alkylene group (including the number of carbon atoms of the substituent, when the alkylene group has a substituent) is preferably 2 or more, more preferably 2 to 10, more preferably 2 to 6, even more preferably 2 to 5, still more preferably 2 to 4, still more preferably 2 or 3, and particularly preferably 2.
The alkylene group may have a substituent, and preferred examples of the substituent include an alkyl group, an aryl group, and a halogen atom.
The number of alkyleneoxy groups contained in the polyalkyleneoxy group (the number of repeating polyalkyleneoxy groups) is preferably 2-20, more preferably 2-10, and even more preferably 2-6.
As the polyalkyleneoxy group, from the viewpoint of solvent solubility and solvent resistance, polyethyleneoxy group, polypropyleneoxy group, polytrimethyleneoxy group, polytetramethyleneoxy group, or a group in which multiple ethyleneoxy groups and multiple propyleneoxy groups are bonded is preferred, polyethyleneoxy group or polypropyleneoxy group is more preferred, and polyethyleneoxy group is even more preferred.In the group in which multiple ethyleneoxy groups and multiple propyleneoxy groups are bonded, the ethyleneoxy groups and the propyleneoxy groups may be arranged randomly, may be arranged in blocks, or may be arranged in a pattern such as alternating.The preferred embodiment of the number of repetitions of the ethyleneoxy group etc. in these groups is as described above.

In formula (2), when R ¹¹³ is a hydrogen atom or when R ¹¹⁴ is a hydrogen atom, the polyimide precursor may form a counter salt with a tertiary amine compound having an ethylenically unsaturated bond. An example of such a tertiary amine compound having an ethylenically unsaturated bond is N,N-dimethylaminopropyl methacrylate.

In formula (2), at least one of R ¹¹³ and R ¹¹⁴ may be a polarity conversion group such as an acid-decomposable group. The acid-decomposable group is not particularly limited as long as it is decomposed by the action of an acid to generate an alkali-soluble group such as a phenolic hydroxy group or a carboxy group, but an acetal group, a ketal group, a silyl group, a silyl ether group, a tertiary alkyl ester group, etc. are preferred, and from the viewpoint of exposure sensitivity, an acetal group or a ketal group is more preferred.
Specific examples of the acid-decomposable group include a tert-butoxycarbonyl group, an isopropoxycarbonyl group, a tetrahydropyranyl group, a tetrahydrofuranyl group, an ethoxyethyl group, a methoxyethyl group, an ethoxymethyl group, a trimethylsilyl group, a tert-butoxycarbonylmethyl group, a trimethylsilyl ether group, etc. From the viewpoint of exposure sensitivity, an ethoxyethyl group or a tetrahydrofuranyl group is preferred.

It is also preferable that the polyimide precursor has fluorine atoms in its structure. The fluorine atom content in the polyimide precursor is preferably 10% by mass or more, and 20% by mass or less.

In order to improve adhesion to the substrate, the polyimide precursor may be copolymerized with an aliphatic group having a siloxane structure. Specific examples include those using bis(3-aminopropyl)tetramethyldisiloxane, bis(p-aminophenyl)octamethylpentasiloxane, etc. as the diamine.

The repeating unit represented by formula (2) is preferably a repeating unit represented by formula (2-A). That is, at least one of the polyimide precursors used in the present invention is preferably a precursor having a repeating unit represented by formula (2-A). By including the repeating unit represented by formula (2-A) in the polyimide precursor, it becomes possible to further increase the width of the exposure latitude.
Formula (2-A)

In formula (2-A), A ¹ and A ² represent an oxygen atom, R ¹¹¹ and R ¹¹² each independently represent a divalent organic group, R ¹¹³ and R ¹¹⁴ each independently represent a hydrogen atom or a monovalent organic group, and at least one of R ¹¹³ and R ¹¹⁴ is a group containing a polymerizable group, and it is preferable that both are groups containing a polymerizable group.

A ¹ , A ² , R ¹¹¹ , R ¹¹³ and R ¹¹⁴ each independently have the same meaning as A ¹ , A ² , R ¹¹¹ , R ¹¹³ and R ¹¹⁴ in formula (2), and the preferred range is also the same. R ¹¹² has the same meaning as R ¹¹² in formula (5), and the preferred range is also the same.

The polyimide precursor may contain one type of repeating unit represented by formula (2), or may contain two or more types. It may also contain a structural isomer of the repeating unit represented by formula (2). The polyimide precursor may contain other types of repeating units in addition to the repeating unit of formula (2).

One embodiment of the polyimide precursor of the present invention is one in which the content of the repeating unit represented by formula (2) is 50 mol% or more of all repeating units. The total content is more preferably 70 mol% or more, even more preferably 90 mol% or more, and particularly preferably more than 90 mol%. There is no particular upper limit to the total content, and all repeating units in the polyimide precursor except for the terminals may be repeating units represented by formula (2).

The weight average molecular weight (Mw) of the polyimide precursor is preferably 5,000 to 100,000, more preferably 10,000 to 50,000, and even more preferably 15,000 to 40,000. The number average molecular weight (Mn) of the polyimide precursor is preferably 2,000 to 40,000, more preferably 3,000 to 30,000, and even more preferably 4,000 to 20,000.
The polyimide precursor has a molecular weight dispersity of preferably 1.5 or more, more preferably 1.8 or more, and even more preferably 2.0 or more. The upper limit of the molecular weight dispersity of the polyimide precursor is not particularly limited, but is, for example, preferably 7.0 or less, more preferably 6.5 or less, and even more preferably 6.0 or less.
In this specification, the dispersity of molecular weight is a value calculated by weight average molecular weight/number average molecular weight.
When the resin composition contains a plurality of polyimide precursors, it is preferable that the weight average molecular weight, number average molecular weight, and dispersity of at least one of the polyimide precursors are within the above ranges. It is also preferable that the weight average molecular weight, number average molecular weight, and dispersity calculated by treating the plurality of polyimide precursors as one resin are each within the above ranges.

[Method for producing polyimide precursor]
The polyimide precursor can be obtained by, for example, a method of reacting a tetracarboxylic dianhydride with a diamine at low temperature, a method of reacting a tetracarboxylic dianhydride with a diamine at low temperature to obtain a polyamic acid, and then esterifying the polyamic acid using a condensing agent or an alkylating agent, a method of obtaining a diester from a tetracarboxylic dianhydride with an alcohol, and then reacting the diamine in the presence of a condensing agent, a method of obtaining a diester from a tetracarboxylic dianhydride with an alcohol, and then acid-halogenating the remaining dicarboxylic acid using a halogenating agent, and then reacting the diamine, etc. Among the above-mentioned production methods, the method of obtaining a diester from a tetracarboxylic dianhydride with an alcohol, and then acid-halogenating the remaining dicarboxylic acid using a halogenating agent, and then reacting the diamine, is more preferable.
Examples of the condensing agent include dicyclohexylcarbodiimide, diisopropylcarbodiimide, 1-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, 1,1-carbonyldioxy-di-1,2,3-benzotriazole, N,N'-disuccinimidyl carbonate, and trifluoroacetic anhydride.
Examples of the alkylating agent include N,N-dimethylformamide dimethyl acetal, N,N-dimethylformamide diethyl acetal, N,N-dialkylformamide dialkyl acetal, trimethyl orthoformate, and triethyl orthoformate.
Examples of the halogenating agent include thionyl chloride, oxalyl chloride, phosphorus oxychloride, and the like.
In the method for producing a polyimide precursor, it is preferable to use an organic solvent in the reaction. The organic solvent may be one type or two or more types.
The organic solvent can be appropriately selected depending on the raw material, and examples thereof include pyridine, diethylene glycol dimethyl ether (diglyme), N-methylpyrrolidone, N-ethylpyrrolidone, ethyl propionate, dimethylacetamide, dimethylformamide, tetrahydrofuran, and γ-butyrolactone.
In the method for producing a polyimide precursor, it is preferable to add a basic compound during the reaction. The basic compound may be one type or two or more types.
The basic compound can be appropriately selected depending on the raw material, and examples thereof include triethylamine, diisopropylethylamine, pyridine, 1,8-diazabicyclo[5.4.0]undec-7-ene, and N,N-dimethyl-4-aminopyridine.

-End-capping agent-
In producing a polyimide precursor, in order to further improve storage stability, it is preferable to cap the carboxylic acid anhydride, acid anhydride derivative, or amino group remaining at the resin terminal of the polyimide precursor, etc. When capping the carboxylic acid anhydride and acid anhydride derivative remaining at the resin terminal, examples of the terminal capping agent include monoalcohols, phenols, thiols, thiophenols, monoamines, etc., and it is more preferable to use monoalcohols, phenols, or monoamines in terms of reactivity and film stability. Preferred monoalcohol compounds include primary alcohols such as methanol, ethanol, propanol, butanol, hexanol, octanol, dodecinol, benzyl alcohol, 2-phenylethanol, 2-methoxyethanol, 2-chloromethanol, and furfuryl alcohol, secondary alcohols such as isopropanol, 2-butanol, cyclohexyl alcohol, cyclopentanol, and 1-methoxy-2-propanol, and tertiary alcohols such as tert-butyl alcohol and adamantane alcohol. Preferred phenolic compounds include phenols such as phenol, methoxyphenol, methylphenol, naphthalene-1-ol, naphthalene-2-ol, and hydroxystyrene. Preferred monoamine compounds include 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-carboxy-7-aminonaphthalene, 1-carboxy-6-aminonaphthalene, 1-carboxy-5-aminonaphthalene, Examples of such an acid include 2-carboxy-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-aminothiophenol, 3-aminothiophenol, and 4-aminothiophenol. Two or more of these may be used, and a plurality of different terminal groups may be introduced by reacting a plurality of terminal blocking agents.
In addition, when the amino group at the resin terminal is blocked, it is possible to block it with a compound having a functional group capable of reacting with the amino group. Preferred blocking agents for the amino group include carboxylic acid anhydrides, carboxylic acid chlorides, carboxylic acid bromides, sulfonic acid chlorides, sulfonic acid anhydrides, sulfonic acid carboxylic acid anhydrides, and the like, and more preferred are carboxylic acid anhydrides and carboxylic acid chlorides. Preferred compounds of carboxylic acid anhydrides include acetic anhydride, propionic anhydride, oxalic anhydride, succinic anhydride, maleic anhydride, phthalic anhydride, benzoic anhydride, 5-norbornene-2,3-dicarboxylic acid anhydride, and the like. Preferred examples of the carboxylic acid chloride include acetyl chloride, acrylic acid chloride, propionyl chloride, methacrylic acid chloride, pivaloyl chloride, cyclohexanecarbonyl chloride, 2-ethylhexanoyl chloride, cinnamoyl chloride, 1-adamantanecarbonyl chloride, heptafluorobutyryl chloride, stearic acid chloride, and benzoyl chloride.

-Solid precipitation-
The production of the polyimide precursor may include a step of precipitating a solid. Specifically, after filtering off the water-absorbing by-product of the dehydration condensation agent coexisting in the reaction solution as necessary, the obtained polymer component is poured into a poor solvent such as water, aliphatic lower alcohol, or a mixture thereof, and the polymer component is precipitated as a solid, and then dried to obtain a polyimide precursor. In order to improve the degree of purification, the polyimide precursor may be repeatedly subjected to operations such as redissolving, reprecipitating, and drying. Furthermore, a step of removing ionic impurities using an ion exchange resin may be included.

〔Content〕
The content of the polyimide precursor in the resin composition is preferably 20% by mass or more, more preferably 30% by mass or more, even more preferably 40% by mass or more, and even more preferably 50% by mass or more, based on the total solid content of the resin composition. The content of the resin in the resin composition is preferably 99.5% by mass or less, more preferably 99% by mass or less, even more preferably 98% by mass or less, even more preferably 97% by mass or less, and even more preferably 95% by mass or less, based on the total solid content of the resin composition.
The resin composition may contain only one type of polyimide precursor, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

It is also preferable that the resin composition contains at least two types of resins.
Specifically, the resin composition may contain a total of two or more kinds of polyimide precursors and other resins described later, or may contain two or more kinds of polyimide precursors, but it is preferable that the resin composition contains two or more kinds of polyimide precursors.
When the resin composition contains two or more kinds of polyimide precursors, for example, it is preferable to contain two or more kinds of polyimide precursors having different dianhydride-derived structures (R ¹¹⁵ in the above formula (2)).

<Other resins>
The resin composition may contain the above-mentioned polyimide precursor and another resin different from the polyimide precursor (hereinafter, simply referred to as "another resin").
Examples of the other resins include polyimide, polybenzoxazole precursor, polybenzoxazole, polyamideimide precursor, polyamideimide, phenol resin, polyamide, epoxy resin, polysiloxane, resin containing a siloxane structure, (meth)acrylic resin, (meth)acrylamide resin, urethane resin, butyral resin, styryl resin, polyether resin, and polyester resin.
Examples of polyimide, polybenzoxazole precursor, polybenzoxazole, polyamideimide precursor, and polyamideimide include the compounds described in paragraphs 0017 to 0138 of WO 2022/145355. The above descriptions are incorporated herein by reference.
For example, by further adding a (meth)acrylic resin, a resin composition having excellent coatability can be obtained, and a pattern (cured product) having excellent solvent resistance can be obtained.
For example, instead of or in addition to the polymerizable compound described later, by adding a (meth)acrylic resin having a weight average molecular weight of 20,000 or less and a high polymerizable group value (for example, the molar content of polymerizable groups per 1 g of resin is 1×10 ⁻³ mol/g or more) to the resin composition, the coatability of the resin composition and the solvent resistance of the pattern (cured product) can be improved.

When the resin composition contains other resins, the content of the other resins is preferably 0.01 mass% or more, more preferably 0.05 mass% or more, even more preferably 1 mass% or more, still more preferably 2 mass% or more, even more preferably 5 mass% or more, and even more preferably 10 mass% or more, based on the total solid content of the resin composition.
The content of other resins in the resin composition is preferably 80 mass% or less, more preferably 75 mass% or less, even more preferably 70 mass% or less, still more preferably 60 mass% or less, and even more preferably 50 mass% or less, based on the total solid content of the resin composition.
As a preferred embodiment of the resin composition, the content of the other resin may be low. In the above embodiment, the content of the other resin is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 5% by mass or less, and even more preferably 1% by mass or less, based on the total solid content of the resin composition. The lower limit of the content is not particularly limited, and may be 0% by mass or more.
The resin composition may contain only one type of other resin, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

<Compound A>
The resin composition preferably contains a compound A having at least one bond selected from a urethane bond and a urea bond, and at least one functional group selected from a tert-butyl group, a hydroxyl group, and a group containing an ethylenically unsaturated bond. When the resin composition contains the compound A, the method for producing a cured product of the present invention satisfies the above-mentioned condition 1.

Compound A is preferably a compound in which a urethane bond or urea bond is cleaved in the heating step described above to produce an amine.

In the present invention, a urethane bond is a bond represented by *--O--C(.dbd.O)-- ^NR.sub.N --*, where ^R.sub.N represents a hydrogen atom or a monovalent organic group, and * represents a bonding site with a carbon atom.
The urea bond is as described above.

Compound A may have only one urea bond or one urethane bond, may have one or more urea bonds and one or more urethane bonds, may have no urethane bond but two or more urea bonds, or may have no urea bond but two or more urethane bonds.
The total number of urea bonds and urethane bonds in compound A is 1 or more, preferably 1 to 10, more preferably 1 to 4, and even more preferably 1 or 2.
When compound A has no urethane bond, the number of urea bonds in compound A is 1 or more, preferably 1 to 10, more preferably 1 to 4, and even more preferably 1 or 2.
When compound A has no urea bond, the number of urethane bonds in compound A is 1 or more, preferably 1 to 10, more preferably 1 to 4, and even more preferably 1 or 2.

Compound A preferably contains at least one compound selected from the group consisting of compounds having a tert-butyl group and a urethane bond, and compounds having a urea bond, two or more hydroxy groups, and a group containing an ethylenically unsaturated bond.

[Compounds Having a tert-Butyl Group]
When compound A is a compound having a tert-butyl group, compound A is preferably an amine in which the amino group is protected with a tert-butoxycarbonyl group.
That is, when compound A is a compound having a tert-butyl group, compound A is preferably a compound having a urethane bond.

Amine compounds protected by a t-butoxycarbonyl group include, for example, ethanolamine, 3-amino-1-propanol, 1-amino-2-propanol, 2-amino-1-propanol, 4-amino-1-butanol, 2-amino-1-butanol, 1-amino-2-butanol, 3-amino-2,2-dimethyl-1-propanol, 4-amino-2-methyl-1-butanol, valinol, 3-amino-1,2-propanediol, 2-amino-1,3-propanediol, Diol, tyramine, norephedrine, 2-amino-1-phenyl-1,3-propanediol, 2-aminocyclohexanol, 4-aminocyclohexanol, 4-aminocyclohexaneethanol, 4-(2-aminoethyl)cyclohexanol, N-methylethanolamine, 3-(methylamino)-1-propanol, 3-(isopropylamino)propanol, N-cyclohexylethanolamine, α-[2-(methylamino)ethyl]benzyl alcohol, diethano diisopropanolamine, 3-pyrrolidinol, 2-pyrrolidinemethanol, 4-hydroxypiperidine, 3-hydroxypiperidine, 4-hydroxy-4-phenylpiperidine, 4-(3-hydroxyphenyl)piperidine, 4-piperidinemethanol, 3-piperidinemethanol, 2-piperidinemethanol, 4-piperidineethanol, 2-piperidineethanol, 2-(4-piperidyl)-2-propanol, 1,4-butanolbis(3-aminopropyl)ethane ether, 1,2-bis(2-aminoethoxy)ethane, 2,2'-oxybis(ethylamine), 1,14-diamino-3,6,9,12-tetraoxatetradecane, 1-aza-15-crown-5-ether, diethylene glycol bis(3-aminopropyl)ether, 1,11-diamino-3,6,9-trioxaundecane, or compounds in which the amino group of an amino acid or a derivative thereof is protected with a t-butoxycarbonyl group, but are not limited to these.

[Compound having a group containing an ethylenically unsaturated bond]
Compound A preferably has a group containing an ethylenically unsaturated bond. The group containing an ethylenically unsaturated bond is more preferably a radical polymerizable group.
The group containing an ethylenically unsaturated bond in compound A is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group (particularly, a (meth)acryloxy group or a (meth)acrylamide group), a vinylphenyl group, and a maleimide group. Of these, a (meth)acryloxy group, a (meth)acrylamide group, a vinylphenyl group, or a maleimide group is preferred, and a (meth)acryloxy group is more preferred.
When compound A has two or more groups containing an ethylenically unsaturated bond, the structures of the groups containing an ethylenically unsaturated bond may be the same or different.
The number of groups containing an ethylenically unsaturated bond in compound A may be one or more, and is preferably 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 4.
The equivalent weight of the group containing an ethylenically unsaturated bond in compound A (the mass of the compound per mole of the group containing an ethylenically unsaturated bond) is preferably 150 to 400 g/mol.
From the viewpoint of the chemical resistance of the cured product, the lower limit of the equivalent weight is more preferably 200 g/mol or more, even more preferably 210 g/mol or more, even more preferably 220 g/mol or more, even more preferably 230 g/mol or more, even more preferably 240 g/mol or more, and particularly preferably 250 g/mol or more.

From the viewpoint of developability, the upper limit of the equivalent weight is more preferably 350 g/mol or less, further preferably 330 g/mol or less, and particularly preferably 300 g/mol or less.
In particular, the equivalent weight is preferably from 210 to 400 g/mol, and more preferably from 220 to 400 g/mol.

It is also preferable that the compound A having a group containing an ethylenically unsaturated bond has at least one of a hydroxy group, an alkoxy group, an alkyleneoxy group, an amino group, an amido group and a cyano group.
From the viewpoint of the chemical resistance of the resulting cured film, the hydroxy group may be an alcoholic hydroxy group or a phenolic hydroxy group, but is preferably an alcoholic hydroxy group.

From the viewpoint of the chemical resistance of the resulting cured film, the alkoxy group is preferably an alkoxy group having 1 to 20 carbon atoms, more preferably an alkoxy group having 1 to 10 carbon atoms, and even more preferably an alkoxy group having 1 to 4 carbon atoms.
From the viewpoint of the chemical resistance of the obtained cured film, the alkyleneoxy group is preferably an alkyleneoxy group having 2 to 20 carbon atoms, more preferably an alkyleneoxy group having 2 to 10 carbon atoms, even more preferably an alkyleneoxy group having 2 to 4 carbon atoms, still more preferably an ethylene group or propylene group, and particularly preferably an ethylene group.
The alkyleneoxy group may be contained as a polyalkyleneoxy group in compound A. In this case, the number of repetitions of the alkyleneoxy group is preferably 2 to 10, and more preferably 2 to 6.
An amide group refers to a bond represented by -C(=O)-NR ^N -. R ^N is as described above. When compound A has an amide group, compound A can contain the amide group, for example, as a group represented by R-C(=O)-NR ^N -* or a group represented by *-C(=O)-NR ^N -R. R represents a hydrogen atom or a monovalent substituent, preferably a hydrogen atom or a hydrocarbon group, and more preferably a hydrogen atom, an alkyl group, or an aromatic hydrocarbon group.
Compound A may have, in the molecule, two or more structures selected from the group consisting of a hydroxy group, an alkyleneoxy group (when a polyalkyleneoxy group is formed, the group is a polyalkyleneoxy group), an amide group, and a cyano group. An embodiment having only one such structure in the molecule is also preferred.
The hydroxy group, alkyleneoxy group, amide group and cyano group may be present at any position of compound A. From the viewpoint of chemical resistance, however, it is also preferable that at least one selected from the group consisting of the hydroxy group, alkyleneoxy group, amide group and cyano group and at least one radical polymerizable group contained in compound A are linked via a linking group containing a urea bond or a urethane bond (hereinafter also referred to as "linking group L2-1").
In particular, when compound A contains only one radically polymerizable group, it is preferable that the radically polymerizable group contained in compound A and at least one selected from the group consisting of a hydroxy group, an alkyleneoxy group, an amide group, and a cyano group are linked via a linking group containing a urea bond or a urethane bond (hereinafter also referred to as "linking group L2-2").
When compound A contains an alkyleneoxy group (however, when it constitutes a polyalkyleneoxy group, it is a polyalkyleneoxy group) and has the linking group L2-1 or the linking group L2-2, the structure bonded to the side of the alkyleneoxy group (however, when it constitutes a polyalkyleneoxy group, it is a polyalkyleneoxy group) opposite to the linking group L2-1 or the linking group L2-2 is not particularly limited, but is preferably a hydrocarbon group, a radically polymerizable group, or a group represented by a combination thereof. As the hydrocarbon group, a hydrocarbon group having 20 or less carbon atoms is preferable, a hydrocarbon group having 18 or less carbon atoms is more preferable, and a hydrocarbon group having 16 or less carbon atoms is even more preferable. As the hydrocarbon group, a saturated aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a group represented by a bond thereof can be mentioned. In addition, a preferred embodiment of the radically polymerizable group is the same as the preferred embodiment of the radically polymerizable group in compound A described above.
When compound A contains an amide group and has the linking group L2-1 or the linking group L2-2, the structure bonded to the side of the amide group opposite to the linking group L2-1 or the linking group L2-2 is not particularly limited, but is preferably a hydrocarbon group, a radically polymerizable group, or a group represented by a combination thereof. The hydrocarbon group is preferably a hydrocarbon group having 20 or less carbon atoms, more preferably a hydrocarbon group having 18 or less carbon atoms, and even more preferably a hydrocarbon group having 16 or less carbon atoms. In addition, examples of the hydrocarbon group include saturated aliphatic hydrocarbon groups, aromatic hydrocarbon groups, and groups represented by a bond between these groups. A preferred embodiment of the radically polymerizable group is the same as the preferred embodiment of the radically polymerizable group in compound A described above. In addition, in the above embodiment, the carbon atom side of the amide group may be bonded to the linking group L2-1 or the linking group L2-2, or the nitrogen atom side of the amide group may be bonded to the linking group L2-1 or the linking group L2-2.
Among these, from the viewpoints of adhesion to the substrate, chemical resistance, and suppression of Cu voids, it is preferable that compound A has a hydroxy group.

Among these, it is preferable that the compound A having a group containing an ethylenically unsaturated bond contains a (meth)acryloyl group and at least one functional group selected from the group consisting of a hydroxy group, an alkoxy group, and an amino group, and it is more preferable that the compound A has a (meth)acryloyl group and a hydroxy group.

In addition, compound A having a group containing an ethylenically unsaturated bond is preferably a compound having a urea bond, two or more hydroxy groups, and a group containing an ethylenically unsaturated bond.

From the viewpoint of compatibility with the polyimide precursor, the compound A having a group containing an ethylenically unsaturated bond also preferably contains an aromatic group.
The aromatic group is preferably directly bonded to a urea bond or a urethane bond contained in compound A. When compound A contains two or more urea bonds or urethane bonds, it is preferable that one of the urea bonds or urethane bonds is directly bonded to the aromatic group.
The aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group, or may have a structure in which these form a condensed ring, but is preferably an aromatic hydrocarbon group.
The aromatic hydrocarbon group is preferably an aromatic hydrocarbon group having 6 to 30 carbon atoms, more preferably an aromatic hydrocarbon group having 6 to 20 carbon atoms, and even more preferably a group in which two or more hydrogen atoms have been removed from a benzene ring structure.
The aromatic heterocyclic group is preferably a 5-membered or 6-membered aromatic heterocyclic group. Examples of the aromatic heterocyclic ring in such an aromatic heterocyclic group include pyrrole, imidazole, triazole, tetrazole, pyrazole, furan, thiophene, oxazole, isoxazole, thiazole, pyridine, pyrazine, pyrimidine, pyridazine, triazine, etc. These rings may be further condensed with other rings, such as indole and benzimidazole.
The heteroatom contained in the aromatic heterocyclic group is preferably a nitrogen atom, an oxygen atom or a sulfur atom.
The aromatic group is preferably contained in, for example, a linking group that links two or more radically polymerizable groups and contains a urea bond or a urethane bond, or a linking group that links at least one selected from the group consisting of the above-mentioned hydroxy group, alkyleneoxy group, amide group, and cyano group to at least one radically polymerizable group contained in compound A.

The compound A having a group containing an ethylenically unsaturated bond preferably has a structure represented by the following formula (U-1), for example.

In formula (U-1), R ^U1 is a hydrogen atom or a monovalent organic group, A is -O- or -NR ^N -, R ^N is a hydrogen atom or a monovalent organic group, Z ^U1 is an m-valent organic group, Z ^U2 is an (n+1)-valent organic group, X is a group containing an ethylenically unsaturated bond, n is an integer of 1 or more, and m is an integer of 1 or more.

R ^U1 is preferably a hydrogen atom, an alkyl group or an aromatic hydrocarbon group, and more preferably a hydrogen atom.
A is —O— or —NR ^N —, and is preferably —NR ^N —.
R ^{3 N} is preferably a hydrogen atom, an alkyl group or an aromatic hydrocarbon group, and more preferably a hydrogen atom.
Z ^U1 is preferably a hydrocarbon group, -O-, -C(=O)-, -S-, -S(=O) ₂ -, -NR ^N -, or a group in which two or more of these are bonded together, and more preferably a hydrocarbon group, or a group in which a hydrocarbon group is bonded to at least one group selected from the group consisting of -O-, -C(=O)-, -S-, -S(=O) ₂ -, and -NR ^N -.
The hydrocarbon group is preferably a hydrocarbon group having 20 or less carbon atoms, more preferably a hydrocarbon group having 18 or less carbon atoms, and even more preferably a hydrocarbon group having 16 or less carbon atoms. Examples of the hydrocarbon group include a saturated aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a group represented by a combination thereof. R ^N represents a hydrogen atom or a monovalent organic group, and is preferably a hydrogen atom or a hydrocarbon group, more preferably a hydrogen atom or an alkyl group, and even more preferably a hydrogen atom or a methyl group.
The above-mentioned hydrocarbon group may have a hydroxy group, an alkoxy group, an alkyleneoxy group, an amino group, an amido group, a cyano group, or the like as a substitute for a hydrogen atom.
In particular, when compound A having a group containing an ethylenically unsaturated bond is a compound having a urea bond, two or more hydroxy groups, and a group containing an ethylenically unsaturated bond, it is preferable that Z ^U1 contains two or more hydroxy groups.
Z ^U2 is preferably a hydrocarbon group, -O-, -C(=O)-, -S-, -S(=O) ₂ -, -NR ^N -, or a group in which two or more of these are bonded together, and more preferably a hydrocarbon group, or a group in which a hydrocarbon group is bonded to at least one group selected from the group consisting of -O-, -C(=O)-, -S-, -S(=O) ₂ -, and -NR ^N -.
The hydrocarbon group includes the same ones as those exemplified for ^ZU1 , and preferred embodiments are also the same.
X is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloxy group, a (meth)acrylamide group, a vinylphenyl group, and a maleimide group. Of these, a (meth)acryloxy group, a (meth)acrylamide group, a vinylphenyl group, or a maleimide group is preferable, and a (meth)acryloxy group is more preferable.
n is preferably an integer of 1 to 10, more preferably an integer of 1 to 4, further preferably 1 or 2, and particularly preferably 1.
m is preferably an integer of 1 to 10, more preferably an integer of 1 to 4, and even more preferably 1 or 2.

In compound A having a group containing an ethylenically unsaturated bond, the number of atoms (linking chain length) between the urea bond or urethane bond and the group containing an ethylenically unsaturated bond is not particularly limited, but is preferably 30 or less, more preferably 2 to 20, and even more preferably 2 to 10.
When compound A contains a total of two or more urea bonds or urethane bonds, when it contains two or more groups containing an ethylenically unsaturated bond, or when it contains two or more urea bonds or urethane bonds and two or more groups containing an ethylenically unsaturated bond, it is sufficient that the minimum number of atoms between the urea bond or urethane bond and the radical polymerizable group (linking chain length) is within the above range.
In this specification, the "number of atoms (linking chain length) between a urea bond or a urethane bond and a polymerizable group" refers to the chain of atoms on the path connecting two atoms or groups of atoms to be linked that links these objects with the shortest length (minimum number of atoms). For example, in the structure represented by the following formula, the number of atoms (linking chain length) between the urea bond and the radical polymerizable group (methacryloyloxy group) is 2.

The method for producing compound A having a polymerizable group is not particularly limited, but for example, it can be obtained by reacting a compound having a group containing an ethylenically unsaturated bond and an isocyanate group with a compound having at least one of a hydroxy group or an amino group.

Specific examples of compound A having a polymerizable group are shown below, but compound A is not limited thereto.

When compound A has a hydroxy group and does not have a group containing an ethylenically unsaturated bond, compound A is preferably a compound represented by the following formula (U-2).

In formula (U-2), A is -O- or -NR ^N -, R ^N is a hydrogen atom or a monovalent organic group, Z ^U3 is an m-valent organic group, R ^U2 each independently represent a monovalent organic group, R ^U3 each independently represent a monovalent organic group, at least one of Z ^U3 , R ^U2 , and R ^U3 is a group having a hydroxyl group, and m is an integer of 1 or more.

In formula (U-2), A is preferably —NR ^N —. R ^N is preferably a hydrogen atom, an alkyl group or a phenyl group, and more preferably a hydrogen atom.

In formula (U-2), Z ^U3 are each independently preferably a hydrocarbon group, -O-, -C(=O)-, -S-, -S(=O) ² -, -NR ^N -, or a group in which two or more of these are bonded together, more preferably a hydrocarbon group, or a group in which a hydrocarbon group is bonded to at least one group selected from the group consisting of -O-, -C(=O)-, -S-, -S(=O) ₂ -, and -NR ^N -, and further preferably a hydrocarbon group.
The hydrocarbon group is preferably a hydrocarbon group having 20 or less carbon atoms, more preferably a hydrocarbon group having 18 or less carbon atoms, and even more preferably a hydrocarbon group having 16 or less carbon atoms. Examples of the hydrocarbon group include a saturated aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a group represented by a combination thereof. R ^N represents a hydrogen atom or a monovalent organic group, and is preferably a hydrogen atom or a hydrocarbon group, more preferably a hydrogen atom or an alkyl group, and even more preferably a hydrogen atom or a methyl group.
The above hydrocarbon group may have a substituent.
In one preferred embodiment of the present invention, the hydrocarbon group has a hydroxy group, an alkyleneoxy group, an amide group, or a cyano group as a substituent. The preferred embodiments of these groups are as described above.

In formula (U-2), each R ^{1 U2} is preferably a hydrocarbon group, more preferably an alkyl group, more preferably an alkyl group having 1 to 20 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms.
The above hydrocarbon group may have a substituent.
In one preferred embodiment of the present invention, the hydrocarbon group has a hydroxy group, an alkyleneoxy group, an amide group, or a cyano group as a substituent. The preferred embodiments of these groups are as described above.

In formula (U-2), preferred embodiments of R ^{1 U3} are the same as those of R ^{1 U2} .

In formula (U-2), m is preferably an integer from 1 to 10, more preferably an integer from 1 to 4, and even more preferably 1 or 2.

[Axis of symmetry]
It is also preferable that compound A is a compound having a structure without an axis of symmetry.
Compound A having no axis of symmetry means that the compound is asymmetric and does not have an axis that would produce an identical molecule to the original molecule by rotating the entire compound. In addition, when the structural formula of compound A is written on paper, compound A having no axis of symmetry means that the structural formula of compound A cannot be written in a form having an axis of symmetry.
It is believed that the absence of an axis of symmetry in compound A suppresses aggregation of compounds A within the composition film.

The resin composition preferably contains, as compound A, any one of U-1 to U-11 in the examples described below.

[Molecular weight]
The molecular weight of compound A is preferably 100 to 2,000, more preferably 150 to 1500, and even more preferably 200 to 900.

The content of compound A relative to the total solid content of the resin composition is preferably 0.1 to 20 mass%. The lower limit is more preferably 0.2 mass% or more, even more preferably 0.4 mass% or more, and particularly preferably 0.6 mass% or more. The upper limit is more preferably 15 mass% or less, even more preferably 12 mass% or less, and particularly preferably 10 mass% or less.
The content of compound A in the resin composition is preferably 0.05 to 15 parts by mass, more preferably 0.10 to 8 parts by mass, based on 100 parts by mass of the polyimide precursor.
Compound A may be used alone or in combination of two or more. When two or more types are used in combination, the total amount is preferably within the above range.

<Polymerizable Compound>
The resin composition preferably contains a polymerizable compound.
The polymerizable compound may include a radical crosslinking agent or other crosslinking agents.
However, the compound corresponding to the above-mentioned compound A is not included in the polymerizable compound referred to here.

[Radical Crosslinking Agent]
The resin composition preferably contains a radical crosslinking agent.
The radical crosslinking agent is a compound having a radical polymerizable group. The radical polymerizable group is preferably a group containing an ethylenically unsaturated bond. Examples of the group containing an ethylenically unsaturated bond include a vinyl group, an allyl group, a vinylphenyl group, a (meth)acryloyl group, a maleimide group, and a (meth)acrylamide group.
Among these, a (meth)acryloyl group, a (meth)acrylamide group, and a vinylphenyl group are preferred, and from the viewpoint of reactivity, a (meth)acryloyl group is more preferred.

The radical crosslinking agent is preferably a compound having one or more ethylenically unsaturated bonds, more preferably a compound having two or more ethylenically unsaturated bonds. The radical crosslinking agent may have three or more ethylenically unsaturated bonds.
As the compound having two or more ethylenically unsaturated bonds, a compound having 2 to 15 ethylenically unsaturated bonds is preferable, a compound having 2 to 10 ethylenically unsaturated bonds is more preferable, and a compound having 2 to 6 ethylenically unsaturated bonds is even more preferable.
From the viewpoint of the film strength of the obtained pattern (cured product), it is also preferable that the resin composition contains a compound having two ethylenically unsaturated bonds and a compound having three or more ethylenically unsaturated bonds. In addition, by using a compound having three or more ethylenically unsaturated bonds, the polymerizable compound itself and the polymer of the polymerizable compound are less likely to volatilize in the decompression step, which is preferable.

The molecular weight of the radical crosslinking agent is preferably 2,000 or less, more preferably 1,500 or less, and even more preferably 900 or less. The lower limit of the molecular weight of the radical crosslinking agent is preferably 100 or more.

Specific examples of radical crosslinking agents include unsaturated carboxylic acids (e.g., acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, etc.) and their esters and amides, preferably esters of unsaturated carboxylic acids and polyhydric alcohol compounds, and amides of unsaturated carboxylic acids and polyvalent amine compounds. In addition, addition reaction products of unsaturated carboxylic acid esters or amides having nucleophilic substituents such as hydroxyl groups, amino groups, and sulfanyl groups with monofunctional or polyfunctional isocyanates or epoxies, and dehydration condensation reaction products of monofunctional or polyfunctional carboxylic acids are also preferably used. In addition, addition reaction products of unsaturated carboxylic acid esters or amides having electrophilic substituents such as isocyanate groups and epoxy groups with monofunctional or polyfunctional alcohols, amines, and thiols, and substitution reaction products of unsaturated carboxylic acid esters or amides having eliminable substituents such as halogeno groups and tosyloxy groups with monofunctional or polyfunctional alcohols, amines, and thiols are also suitable. As another example, it is also possible to use a compound group in which the above unsaturated carboxylic acid is replaced with an unsaturated phosphonic acid, a vinylbenzene derivative such as styrene, a vinyl ether, an allyl ether, etc. Specific examples can be found in paragraphs 0113 to 0122 of JP 2016-027357 A, the contents of which are incorporated herein by reference.

The radical crosslinking agent is preferably a compound having a boiling point of 100°C or higher under normal pressure. Examples of compounds having a boiling point of 100°C or higher under normal pressure include the compounds described in paragraph 0203 of WO 2021/112189, the contents of which are incorporated herein by reference.

Preferable radical crosslinking agents other than those mentioned above include the radical polymerizable compounds described in paragraphs 0204 to 0208 of WO 2021/112189, the contents of which are incorporated herein by reference.

Preferred radical crosslinking agents are dipentaerythritol triacrylate (commercially available products include KAYARAD D-330 (manufactured by Nippon Kayaku Co., Ltd.)), dipentaerythritol tetraacrylate (commercially available products include KAYARAD D-320 (manufactured by Nippon Kayaku Co., Ltd.) and A-TMMT (manufactured by Shin-Nakamura Chemical Co., Ltd.)), dipentaerythritol penta(meth)acrylate (commercially available products include KAYARAD D-310 (manufactured by Nippon Kayaku Co., Ltd.)), dipentaerythritol hexa(meth)acrylate (commercially available products include KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.) and A-DPH (manufactured by Shin-Nakamura Chemical Co., Ltd.)), and structures in which the (meth)acryloyl groups are bonded via ethylene glycol residues or propylene glycol residues. Oligomer types of these can also be used.

Commercially available radical crosslinking agents include, for example, SR-494, a tetrafunctional acrylate with four ethyleneoxy chains, SR-209, 231, and 239, which are difunctional methacrylates with four ethyleneoxy chains (all manufactured by Sartomer Corporation), DPCA-60, a hexafunctional acrylate with six pentyleneoxy chains, TPA-330, a trifunctional acrylate with three isobutyleneoxy chains (all manufactured by Nippon Kayaku Co., Ltd.), and urethane oligomers. Examples include UAS-10 and UAB-140 (all manufactured by Nippon Paper Industries Co., Ltd.), NK Ester M-40G, NK Ester 4G, NK Ester M-9300, NK Ester A-9300, and UA-7200 (all manufactured by Shin-Nakamura Chemical Co., Ltd.), DPHA-40H (manufactured by Nippon Kayaku Co., Ltd.), UA-306H, UA-306T, UA-306I, AH-600, T-600, and AI-600 (all manufactured by Kyoeisha Chemical Co., Ltd.), and Blenmar PME400 (manufactured by NOF Corp.).

As radical crosslinking agents, urethane acrylates such as those described in JP-B-48-041708, JP-A-51-037193, JP-B-02-032293, and JP-B-02-016765, and urethane compounds having an ethylene oxide skeleton described in JP-B-58-049860, JP-B-56-017654, JP-B-62-039417, and JP-B-62-039418 are also suitable. As radical crosslinking agents, compounds having an amino structure or sulfide structure in the molecule, as described in JP-A-63-277653, JP-A-63-260909, and JP-A-01-105238, can also be used.

The radical crosslinking agent may be a radical crosslinking agent having an acid group such as a carboxy group or a phosphate group. The radical crosslinking agent having an acid group is preferably an ester of an aliphatic polyhydroxy compound and an unsaturated carboxylic acid, and more preferably a radical crosslinking agent in which an acid group is provided by reacting an unreacted hydroxy group of an aliphatic polyhydroxy compound with a non-aromatic carboxylic anhydride. Particularly preferred is a radical crosslinking agent in which an acid group is provided by reacting an unreacted hydroxy group of an aliphatic polyhydroxy compound with a non-aromatic carboxylic anhydride, in which the aliphatic polyhydroxy compound is pentaerythritol or dipentaerythritol. Examples of commercially available products include polybasic acid modified acrylic oligomers manufactured by Toagosei Co., Ltd., such as M-510 and M-520.

The acid value of the radical crosslinking agent having an acid group is preferably 0.1 to 300 mgKOH/g, more preferably 1 to 100 mgKOH/g. If the acid value of the radical crosslinking agent is within the above range, the agent has excellent handling properties during manufacturing and developability. In addition, the agent has good polymerizability. The acid value is measured in accordance with the description of JIS K 0070:1992.

From the viewpoints of pattern resolution and film stretchability, it is preferable to use a difunctional methacrylate or acrylate for the resin composition.
Specific examples of the compounds include triethylene glycol diacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, tetraethylene glycol diacrylate, PEG (polyethylene glycol) 200 diacrylate, PEG 200 dimethacrylate, PEG 600 diacrylate, PEG 600 dimethacrylate, polytetraethylene glycol diacrylate, polytetraethylene glycol dimethacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, neopentyl glycol diacrylate, neopentyl glycol dimethacrylate, 3-methyl-1,5-pentanediol diacrylate, 1,6-hexyl 1,5-dimethylphenyl ... Xanediol diacrylate, 1,6-hexanediol dimethacrylate, dimethylol-tricyclodecane diacrylate, dimethylol-tricyclodecane dimethacrylate, EO (ethylene oxide) adduct diacrylate of bisphenol A, EO adduct dimethacrylate of bisphenol A, PO (propylene oxide) adduct diacrylate of bisphenol A, PO adduct dimethacrylate of bisphenol A, 2-hydroxy-3-acryloyloxypropyl methacrylate, isocyanuric acid EO-modified diacrylate, isocyanuric acid EO-modified dimethacrylate, other bifunctional acrylates having a urethane bond, and bifunctional methacrylates having a urethane bond can be used. Two or more of these can be mixed and used as necessary.
For example, PEG200 diacrylate refers to polyethylene glycol diacrylate with a formula weight of about 200 for the polyethylene glycol chain.
In terms of suppressing warping of the pattern (cured product), the resin composition can preferably use a monofunctional radical crosslinking agent as the radical crosslinking agent. As the monofunctional radical crosslinking agent, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, carbitol (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, N-methylol (meth)acrylamide, glycidyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, and other (meth)acrylic acid derivatives, N-vinyl compounds such as N-vinylpyrrolidone and N-vinylcaprolactam, and allyl glycidyl ether are preferably used. As the monofunctional radical crosslinking agent, a compound having a boiling point of 100° C. or higher under normal pressure is also preferred in order to suppress volatilization before exposure.
Other examples of the difunctional or higher radical crosslinking agent include allyl compounds such as diallyl phthalate and triallyl trimellitate.

When a radical crosslinking agent is contained, the content of the radical crosslinking agent is preferably more than 0 mass% and not more than 60 mass% based on the total solid content of the resin composition. The lower limit is more preferably 5 mass% or more. The upper limit is more preferably 50 mass% or less, and even more preferably 30 mass% or less.

The radical crosslinking agent may be used alone or in combination of two or more. When two or more types are used in combination, it is preferable that the total amount is within the above range.

[Other crosslinking agents]
The resin composition also preferably contains another crosslinking agent different from the above-mentioned radical crosslinking agent.
The other crosslinking agent refers to a crosslinking agent other than the above-mentioned radical crosslinking agent, and is preferably a compound having, in its molecule, a plurality of groups that promote a reaction to form a covalent bond with another compound in the composition or a reaction product thereof upon exposure to light by the above-mentioned photoacid generator or photobase generator, and is preferably a compound having, in its molecule, a plurality of groups that promote a reaction to form a covalent bond with another compound in the composition or a reaction product thereof under the action of an acid or a base.
The acid or base is preferably an acid or base generated from a photoacid generator or a photobase generator in the exposure step.
Other cross-linking agents include the compounds described in paragraphs 0179 to 0207 of WO 2022/145355, the disclosures of which are incorporated herein by reference.

The content of the other crosslinking agent is preferably 0.1 to 30 mass% relative to the total solid content of the resin composition, more preferably 0.1 to 20 mass%, even more preferably 0.5 to 15 mass%, and particularly preferably 1.0 to 10 mass%. Only one type of other crosslinking agent may be contained, or two or more types may be contained. When two or more types of other crosslinking agents are contained, the total is preferably within the above range.

[Polymerization initiator]
The resin composition preferably contains a polymerization initiator. The polymerization initiator may be a thermal polymerization initiator or a photopolymerization initiator, but it is particularly preferable that the resin composition contains a photopolymerization initiator.
The photopolymerization initiator is preferably a photoradical polymerization initiator. The photoradical polymerization initiator is not particularly limited and can be appropriately selected from known photoradical polymerization initiators. For example, a photoradical polymerization initiator having photosensitivity to light rays in the ultraviolet to visible regions is preferable. Alternatively, it may be an activator that reacts with a photoexcited sensitizer to generate active radicals.

The photoradical polymerization initiator preferably contains at least one compound having a molar absorption coefficient of at least about 50 L·mol ⁻¹ ·cm ⁻¹ in a wavelength range of about 240 to 800 nm (preferably 330 to 500 nm). The molar absorption coefficient of the compound can be measured using a known method. For example, it is preferable to measure it using an ultraviolet-visible spectrophotometer (Varian Cary-5 spectrophotometer) at a concentration of 0.01 g/L using ethyl acetate as a solvent.

Any known compound can be used as the photoradical polymerization initiator. For example, halogenated hydrocarbon derivatives (e.g., compounds having a triazine skeleton, compounds having an oxadiazole skeleton, compounds having a trihalomethyl group, etc.), acylphosphine compounds such as acylphosphine oxides, hexaarylbiimidazoles, oxime compounds such as oxime derivatives, organic peroxides, thio compounds, ketone compounds, aromatic onium salts, ketoxime ethers, α-aminoketone compounds such as aminoacetophenones, α-hydroxyketone compounds such as hydroxyacetophenones, azo compounds, azide compounds, metallocene compounds, organic boron compounds, iron arene complexes, etc. For details of these, please refer to the descriptions in paragraphs 0165 to 0182 of JP 2016-027357 A and paragraphs 0138 to 0151 of WO 2015/199219, the contents of which are incorporated herein by reference. Further examples include the compounds described in paragraphs 0065 to 0111 of JP 2014-130173 A and JP 6301489 A, the peroxide-based photopolymerization initiators described in MATERIAL STAGE 37 to 60p, vol. 19, No. 3, 2019, the photopolymerization initiators described in WO 2018/221177 A, the photopolymerization initiators described in WO 2018/110179 A, the photopolymerization initiators described in JP 2019-043864 A, the photopolymerization initiators described in JP 2019-044030 A, and the peroxide-based initiators described in JP 2019-167313 A, the contents of which are incorporated herein by reference.

Examples of ketone compounds include the compounds described in paragraph 0087 of JP 2015-087611 A, the contents of which are incorporated herein by reference. As a commercially available product, Kayacure-DETX-S (manufactured by Nippon Kayaku Co., Ltd.) is also preferably used.

In one embodiment of the present invention, hydroxyacetophenone compounds, aminoacetophenone compounds, and acylphosphine compounds can be suitably used as photoradical polymerization initiators. More specifically, for example, aminoacetophenone-based initiators described in JP-A-10-291969 and acylphosphine oxide-based initiators described in Japanese Patent No. 4225898 can be used, the contents of which are incorporated herein by reference.

α-Hydroxyketone initiators that can be used include Omnirad 184, Omnirad 1173, Omnirad 2959, Omnirad 127 (all manufactured by IGM Resins B.V.), IRGACURE 184 (IRGACURE is a registered trademark), DAROCUR 1173, IRGACURE 500, IRGACURE-2959, and IRGACURE 127 (all manufactured by BASF).

As α-aminoketone initiators, Omnirad 907, Omnirad 369, Omnirad 369E, Omnirad 379EG (all manufactured by IGM Resins B.V.), IRGACURE 907, IRGACURE 369, and IRGACURE 379 (all manufactured by BASF) can be used.

As the aminoacetophenone initiator, acylphosphine oxide initiator, and metallocene compound, for example, the compounds described in paragraphs 0161 to 0163 of WO 2021/112189 can also be suitably used. The contents of this specification are incorporated herein.

As a photoradical polymerization initiator, an oxime compound is more preferably used. By using an oxime compound, it becomes possible to more effectively improve the exposure latitude. Oxime compounds are particularly preferred because they have a wide exposure latitude (exposure margin) and also function as a photocuring accelerator.

The resin composition preferably contains a compound represented by the following formula (PPI-1) as a photopolymerization initiator. By containing the compound represented by the following formula (PPI-1), the photopolymerization system reacts sufficiently when exposed to light and is easily removed by a decompression step, so that a cured product with excellent heat resistance reliability can be obtained.

In formula (PPI-1), R ¹ is an organic group having 1 to 9 carbon atoms, R ² is a methyl group or a phenyl group, R ³ is each independently an organic group having 1 to 9 carbon atoms, and n is an integer of 0 to 5.

In formula (PPI-1), R ¹ is preferably a hydrocarbon group, more preferably an alkyl group.
The above-mentioned hydrocarbon group (alkyl group) is preferably a hydrocarbon group (alkyl group) having 2 to 20 carbon atoms, and more preferably a hydrocarbon group (alkyl group) having 4 to 10 carbon atoms.
The hydrocarbon group may be linear, branched, cyclic, or a combination thereof.
Among these, ^R1 is preferably a linear alkyl group, a branched alkyl group, a cyclic alkyl group, or a structure in which a hydrogen atom of a linear alkyl group is substituted with a cyclic alkyl group. The preferred number of carbon atoms of these groups is the same as the preferred number of carbon atoms of the above-mentioned hydrocarbon group.
Specific examples of ^R1 include an n-hexyl group, a 1-methylbutyl group, a cyclohexylmethyl group, and a cyclohexyl group.

In formula (PPI-1), ^R3 is not particularly limited, but examples thereof include an alkyl group, an aryl group, an alkoxy group, an aryloxy group, and a group represented by -C(=O)R.
The above R is not particularly limited, and examples thereof include an alkyl group, an aryl group, a heteroaliphatic ring group, or a group represented by a combination thereof.

In formula (PPI-1), n is preferably an integer of 0 to 2, and more preferably 0 or 1. An embodiment in which n is 0 is also one of the preferred embodiments of the present invention.

Specific examples of oxime compounds include the compounds described in JP-A-2001-233842, the compounds described in JP-A-2000-080068, the compounds described in JP-A-2006-342166, the compounds described in J. C. S. Perkin II (1979, pp. 1653-1660), the compounds described in J. C. S. Compounds described in Perkin II (1979, pp. 156-162), compounds described in Journal of Photopolymer Science and Technology (1995, pp. 202-232), compounds described in JP-A-2000-066385, compounds described in JP-T-2004-534797, compounds described in JP-A-2017-019766, Examples of the compounds include those described in WO 6065596, WO 2015/152153, WO 2017/051680, JP 2017-198865, WO 2017/164127, paragraphs 0025 to 0038, and WO 2013/167515, the contents of which are incorporated herein by reference.

Preferred oxime compounds include, for example, compounds having the following structure, 3-(benzoyloxy(imino))butan-2-one, 3-(acetoxy(imino))butan-2-one, 3-(propionyloxy(imino))butan-2-one, 2-(acetoxy(imino))pentan-3-one, 2-(acetoxy(imino))-1-phenylpropan-1-one, 2-(benzoyloxy(imino))-1-phenylpropan-1-one, 3-((4-toluenesulfonyloxy)imino)butan-2-one, and 2-(ethoxycarbonyloxy(imino))-1-phenylpropan-1-one. In the resin composition, it is particularly preferable to use an oxime compound as a photoradical polymerization initiator. The oxime compound as a photoradical polymerization initiator has a linking group of >C=N-O-C(=O)- in the molecule.

Commercially available oxime compounds include IRGACURE OXE 01, IRGACURE OXE 02, IRGACURE OXE 03, IRGACURE OXE 04 (manufactured by BASF), ADEKA OPTOMER N-1919 (manufactured by ADEKA Corporation, photoradical polymerization initiator 2 described in JP-A-2012-014052), TR-PBG-304, TR-PBG-305 (manufactured by Changzhou Strong Electronic New Materials Co., Ltd.), ADEKA ARCLES NCI-730, NCI-831 and ADEKA ARCLES NCI-930 (manufactured by ADEKA Corporation), DFI-091 (manufactured by Daito Chemistry Co., Ltd.), and SpeedCure PDO (manufactured by SARTOMER ARKEMA). In addition, an oxime compound having the following structure can also be used.

As the photoradical polymerization initiator, for example, an oxime compound having a fluorene ring described in paragraphs 0169 to 0171 of WO 2021/112189, an oxime compound having a skeleton in which at least one benzene ring of a carbazole ring is a naphthalene ring, or an oxime compound having a fluorine atom can be used.
In addition, oxime compounds having a nitro group, oxime compounds having a benzofuran skeleton, and oxime compounds having a hydroxyl group-containing substituent bonded to a carbazole skeleton described in paragraphs 0208 to 0210 of WO 2021/020359 can also be used. The contents of these compounds are incorporated herein by reference.

As the photopolymerization initiator, an oxime compound having an aromatic ring group Ar ^OX1 in which an electron-withdrawing group is introduced into an aromatic ring (hereinafter, also referred to as oxime compound OX) can also be used. The electron-withdrawing group of the aromatic ring group Ar ^OX1 includes an acyl group, a nitro group, a trifluoromethyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, and a cyano group. An acyl group and a nitro group are preferred, and an acyl group is more preferred because it is easy to form a film with excellent light resistance, and a benzoyl group is even more preferred. The benzoyl group may have a substituent. The substituent is preferably a halogen atom, a cyano group, a nitro group, a hydroxy group, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic group, a heterocyclic oxy group, an alkenyl group, an alkylsulfanyl group, an arylsulfanyl group, an acyl group, or an amino group, more preferably an alkyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic oxy group, an alkylsulfanyl group, an arylsulfanyl group, or an amino group, and further preferably an alkoxy group, an alkylsulfanyl group, or an amino group.

The oxime compound OX is preferably at least one selected from the compounds represented by the formula (OX1) and the compounds represented by the formula (OX2), and more preferably the compound represented by the formula (OX2).

In the formula, R ^X1 represents an alkyl group, an alkenyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic group, a heterocyclic oxy group, an alkylsulfanyl group, an arylsulfanyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, an acyl group, an acyloxy group, an amino group, a phosphinoyl group, a carbamoyl group, or a sulfamoyl group;
R ^X2 represents an alkyl group, an alkenyl group, an alkoxy group, an aryl group, an aryloxy group, a heterocyclic group, a heterocyclic oxy group, an alkylsulfanyl group, an arylsulfanyl group, an alkylsulfinyl group, an arylsulfinyl group, an alkylsulfonyl group, an arylsulfonyl group, an acyloxy group, or an amino group;
R ^X3 to R ^X14 each independently represent a hydrogen atom or a substituent.
However, at least one of R ^X10 to R ^X14 is an electron-withdrawing group.

In the above formula, it is preferable that R ^X12 is an electron-withdrawing group, and R ^X10 , R ^X11 , R ^X13 and R ^X14 are each a hydrogen atom.

Specific examples of oxime compounds OX include the compounds described in paragraphs 0083 to 0105 of Japanese Patent No. 4600600, the contents of which are incorporated herein by reference.

Particularly preferred oxime compounds include oxime compounds having specific substituents as disclosed in JP 2007-269779 A and oxime compounds having thioaryl groups as disclosed in JP 2009-191061 A, the contents of which are incorporated herein by reference.

From the viewpoint of exposure sensitivity, the photoradical polymerization initiator is preferably a compound selected from the group consisting of trihalomethyltriazine compounds, benzyl dimethyl ketal compounds, α-hydroxyketone compounds, α-aminoketone compounds, acylphosphine compounds, phosphine oxide compounds, metallocene compounds, oxime compounds, triarylimidazole dimers, onium salt compounds, benzothiazole compounds, benzophenone compounds, acetophenone compounds and derivatives thereof, cyclopentadiene-benzene-iron complexes and salts thereof, halomethyloxadiazole compounds, and 3-aryl substituted coumarin compounds.

The photoradical polymerization initiator is a trihalomethyltriazine compound, an α-aminoketone compound, an acylphosphine compound, a phosphine oxide compound, a metallocene compound, an oxime compound, a triarylimidazole dimer, an onium salt compound, a benzophenone compound, or an acetophenone compound. At least one compound selected from the group consisting of a trihalomethyltriazine compound, an α-aminoketone compound, a metallocene compound, an oxime compound, a triarylimidazole dimer, or a benzophenone compound is more preferred, and a metallocene compound or an oxime compound is even more preferred.

As the photoradical polymerization initiator, the compounds described in paragraphs [0175] to [0179] of WO 2021/020359 and the compounds described in paragraphs [0048] to [0055] of WO 2015/125469 can also be used, the contents of which are incorporated herein by reference.

As the photoradical polymerization initiator, a bifunctional or trifunctional or higher functional photoradical polymerization initiator may be used. By using such a photoradical polymerization initiator, two or more radicals are generated from one molecule of the photoradical polymerization initiator, resulting in good sensitivity. Furthermore, when a compound with an asymmetric structure is used, crystallinity decreases and solubility in solvents improves, making it less likely to precipitate over time, and improving the stability of the resin composition over time. Specific examples of bifunctional or trifunctional or higher functional photoradical polymerization initiators include dimers of oxime compounds described in JP-T-2010-527339, JP-T-2011-524436, WO-2015/004565, WO-2016-532675, paragraphs 0407 to 0412, and WO-2017/033680, paragraphs 0039 to 0055; compound (E) and compound (G) described in WO-T-2013-522445; Examples of such initiators include Cmpd1 to 7 described in Japanese Patent Publication No. 4963, the oxime ester photoinitiators described in paragraph 0007 of JP-T-2017-523465, the photoinitiators described in paragraphs 0020 to 0033 of JP-A-2017-167399, the photopolymerization initiator (A) described in paragraphs 0017 to 0026 of JP-A-2017-151342, and the oxime ester photoinitiators described in Japanese Patent Publication No. 6469669, the contents of which are incorporated herein by reference.

When the resin composition contains a photopolymerization initiator, the content is preferably 0.1 to 30 mass% based on the total solid content of the resin composition, more preferably 0.1 to 20 mass%, even more preferably 0.5 to 15 mass%, and even more preferably 1.0 to 10 mass%. Only one type of photopolymerization initiator may be contained, or two or more types may be contained. When two or more types of photopolymerization initiators are contained, the total amount is preferably within the above range.
In addition, since the photopolymerization initiator may also function as a thermal polymerization initiator, the crosslinking caused by the photopolymerization initiator may be further promoted by heating in an oven, a hot plate, or the like.

[Sensitizer]
The resin composition may contain a sensitizer. The sensitizer absorbs specific active radiation and becomes electronically excited. The sensitizer in the electronically excited state comes into contact with a thermal radical polymerization initiator, a photoradical polymerization initiator, or the like, and effects such as electron transfer, energy transfer, and heat generation occur. As a result, the thermal radical polymerization initiator and the photoradical polymerization initiator undergo a chemical change and are decomposed to generate a radical, an acid, or a base.
Usable sensitizers include benzophenone-based, Michler's ketone-based, coumarin-based, pyrazole azo-based, anilino azo-based, triphenylmethane-based, anthraquinone-based, anthracene-based, anthrapyridone-based, benzylidene-based, oxonol-based, pyrazolotriazole azo-based, pyridone azo-based, cyanine-based, phenothiazine-based, pyrrolopyrazole azomethine-based, xanthene-based, phthalocyanine-based, benzopyran-based, indigo-based compounds, and the like.
Examples of the sensitizer include Michler's ketone, 4,4'-bis(diethylamino)benzophenone, 2,5-bis(4'-diethylaminobenzal)cyclopentane, 2,6-bis(4'-diethylaminobenzal)cyclohexanone, 2,6-bis(4'-diethylaminobenzal)-4-methylcyclohexanone, 4,4'-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, p-dimethylaminocinnamylidene indanone, and p-dimethylaminobenzylidene indanone. Non, 2-(p-dimethylaminophenylbiphenylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)isonaphthothiazole, 1,3-bis(4'-dimethylaminobenzal)acetone, 1,3-bis(4'-diethylaminobenzal)acetone, 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3-acetyl-7-dimethylaminocoumarin, 3-ethoxycarbonyl-7-dimethylaminocoumarin phosphorus, 3-benzyloxycarbonyl-7-dimethylaminocoumarin, 3-methoxycarbonyl-7-diethylaminocoumarin, 3-ethoxycarbonyl-7-diethylaminocoumarin (7-(diethylamino)coumarin-3-carboxylate ethyl), N-phenyl-N'-ethylethanolamine, N-phenyldiethanolamine, N-p-tolyldiethanolamine, N-phenylethanolamine, 4-morpholinobenzophenone, isoamyl dimethylaminobenzoate, isoethylaminobenzoate Examples of such an alkyl ester include soamyl, 2-mercaptobenzimidazole, 1-phenyl-5-mercaptotetrazole, 2-mercaptobenzothiazole, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzothiazole, 2-(p-dimethylaminostyryl)naphtho(1,2-d)thiazole, 2-(p-dimethylaminobenzoyl)styrene, diphenylacetamide, benzanilide, N-methylacetanilide, and 3',4'-dimethylacetanilide.
Other sensitizing dyes may also be used.
For details about the sensitizing dye, the description in paragraphs [0161] to [0163] of JP2016-027357A can be referred to, the contents of which are incorporated herein by reference.

When the resin composition contains a sensitizer, the content of the sensitizer is preferably 0.01 to 20 mass % relative to the total solid content of the resin composition, more preferably 0.1 to 15 mass %, and even more preferably 0.5 to 10 mass %. The sensitizer may be used alone or in combination of two or more types.

[Chain transfer agent]
The resin composition may contain a chain transfer agent. The chain transfer agent is defined, for example, in the Third Edition of the Polymer Dictionary (edited by the Society of Polymer Science, 2005), pages 683-684. Examples of the chain transfer agent include compounds having -S-S-, -SO ₂ -S-, -N-O-, SH, PH, SiH, and GeH in the molecule, and dithiobenzoate, trithiocarbonate, dithiocarbamate, and xanthate compounds having a thiocarbonylthio group used in RAFT (Reversible Addition Fragmentation Chain Transfer) polymerization. These donate hydrogen to a low activity radical to generate a radical, or are oxidized and then deprotonated to generate a radical. In particular, a thiol compound can be preferably used.

In addition, the chain transfer agent may be the compound described in paragraphs 0152 to 0153 of International Publication No. 2015/199219, the contents of which are incorporated herein by reference.

When the resin composition contains a chain transfer agent, the content of the chain transfer agent is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and even more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the total solid content of the resin composition. The chain transfer agent may be one type or two or more types. When there are two or more types of chain transfer agents, the total is preferably within the above range.

<Base Generator>
The resin composition may contain a base generator. Here, the base generator is a compound capable of generating a base by physical or chemical action. Preferred base generators include a thermal base generator and a photobase generator.
However, the compound corresponding to the above-mentioned compound A does not correspond to the base generator as defined herein.
In particular, when the resin composition contains a precursor of a cyclized resin, the resin composition preferably contains a base generator. By containing the thermal base generator in the resin composition, for example, the cyclization reaction of the precursor can be promoted by heating, and the mechanical properties and chemical resistance of the cured product can be improved, and the performance as an interlayer insulating film for a rewiring layer contained in a semiconductor package can be improved.
The base generator may be an ionic base generator or a nonionic base generator. Examples of the base generated from the base generator include secondary amines and tertiary amines.
The base generator is not particularly limited, and a known base generator can be used. Examples of known base generators include carbamoyl oxime compounds, carbamoyl hydroxylamine compounds, carbamic acid compounds, formamide compounds, acetamide compounds, carbamate compounds, benzyl carbamate compounds, nitrobenzyl carbamate compounds, sulfonamide compounds, imidazole derivative compounds, amine imide compounds, pyridine derivative compounds, α-aminoacetophenone derivative compounds, quaternary ammonium salt derivative compounds, iminium salts, pyridinium salts, α-lactone ring derivative compounds, amine imide compounds, phthalimide derivative compounds, and acyloxyimino compounds.
Specific examples of the non-ionic base generator include the compounds described in paragraphs 0249 to 0275 of WO 2022/145355. The above descriptions are incorporated herein by reference.

Base generators include, but are not limited to, the following compounds:

The molecular weight of the nonionic base generator is preferably 800 or less, more preferably 600 or less, and even more preferably 500 or less. The lower limit is preferably 100 or more, more preferably 200 or more, and even more preferably 300 or more.

Specific preferred compounds for the ionic base generator include, for example, the compounds described in paragraphs 0148 to 0163 of WO 2018/038002.

Specific examples of ammonium salts include, but are not limited to, the following compounds:

Specific examples of iminium salts include, but are not limited to, the following compounds:

When the resin composition contains a base generator, the content of the base generator is preferably 0.1 to 50 parts by mass relative to 100 parts by mass of the resin in the resin composition. The lower limit is more preferably 0.3 parts by mass or more, and even more preferably 0.5 parts by mass or more. The upper limit is more preferably 30 parts by mass or less, even more preferably 20 parts by mass or less, even more preferably 10 parts by mass or less, even more preferably 5 parts by mass or less, and particularly preferably 4 parts by mass or less.
The base generator may be used alone or in combination of two or more. When two or more types are used, the total amount is preferably within the above range.

<Solvent>
The resin composition contains a solvent.
The solvent may be any known solvent. The solvent is preferably an organic solvent. Examples of the organic solvent include compounds such as esters, ethers, ketones, cyclic hydrocarbons, sulfoxides, amides, ureas, and alcohols.

Esters, for example, ethyl acetate, n-butyl acetate, isobutyl acetate, hexyl acetate, amyl formate, isoamyl acetate, butyl propionate, isopropyl butyrate, ethyl butyrate, butyl butyrate, methyl lactate, ethyl lactate, γ-butyrolactone, ε-caprolactone, δ-valerolactone, γ-valerolactone, alkyloxyacetates (for example, methyl alkyloxyacetate, ethyl alkyloxyacetate, butyl alkyloxyacetate (for example, methyl methoxyacetate, ethyl methoxyacetate, butyl methoxyacetate, methyl ethoxyacetate, ethyl ethoxyacetate, etc.)), 3-alkyloxypropionic acid alkyl esters (for example, methyl 3-alkyloxypropionate, ethyl 3-alkyloxypropionate, etc. (for example, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, etc.)), 2- Suitable examples of alkyloxypropionic acid alkyl esters include alkyl esters (e.g., methyl 2-alkyloxypropionate, ethyl 2-alkyloxypropionate, propyl 2-alkyloxypropionate, etc. (e.g., methyl 2-methoxypropionate, ethyl 2-methoxypropionate, propyl 2-methoxypropionate, methyl 2-ethoxypropionate, ethyl 2-ethoxypropionate)), methyl 2-alkyloxy-2-methylpropionate and ethyl 2-alkyloxy-2-methylpropionate (e.g., methyl 2-methoxy-2-methylpropionate, ethyl 2-ethoxy-2-methylpropionate, etc.), methyl pyruvate, ethyl pyruvate, propyl pyruvate, methyl acetoacetate, ethyl acetoacetate, methyl 2-oxobutanoate, ethyl 2-oxobutanoate, ethyl hexanoate, ethyl heptanoate, dimethyl malonate, diethyl malonate, etc.

Suitable examples of ethers include ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol butyl methyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, tetrahydrofuran, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol ethyl methyl ether, propylene glycol monopropyl ether acetate, and dipropylene glycol dimethyl ether.

Preferred examples of ketones include methyl ethyl ketone, cyclohexanone, cyclopentanone, 2-heptanone, 3-heptanone, 3-methylcyclohexanone, levoglucosenone, and dihydrolevoglucosenone.

Preferable examples of cyclic hydrocarbons include aromatic hydrocarbons such as toluene, xylene, and anisole, and cyclic terpenes such as limonene.

As an example of a sulfoxide, dimethyl sulfoxide is preferred.

Preferred examples of amides include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, N,N-dimethylisobutyramide, 3-methoxy-N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide, N-formylmorpholine, and N-acetylmorpholine.

Preferred examples of ureas include N,N,N',N'-tetramethylurea and 1,3-dimethyl-2-imidazolidinone.

Alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 1-pentanol, 1-hexanol, benzyl alcohol, ethylene glycol monomethyl ether, 1-methoxy-2-propanol, 2-ethoxyethanol, diethylene glycol monoethyl ether, diethylene glycol monohexyl ether, triethylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monomethyl ether, polyethylene glycol monomethyl ether, polypropylene glycol, tetraethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monobenzyl ether, ethylene glycol monophenyl ether, methylphenyl carbinol, n-amyl alcohol, methylamyl alcohol, and diacetone alcohol.

From the standpoint of improving the properties of the coating surface, it is also preferable to mix two or more types of solvents.

In the present invention, one solvent selected from methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl cellosolve acetate, ethyl lactate, diethylene glycol dimethyl ether, butyl acetate, methyl 3-methoxypropionate, 2-heptanone, cyclohexanone, cyclopentanone, γ-butyrolactone, γ-valerolactone, 3-methoxy-N,N-dimethylpropionamide, toluene, dimethyl sulfoxide, ethyl carbitol acetate, butyl carbitol acetate, N-methyl-2-pyrrolidone, propylene glycol methyl ether, propylene glycol methyl ether acetate, levoglucosenone, and dihydrolevoglucosenone, or a mixed solvent composed of two or more solvents, is preferred. Particularly preferred are a combination of dimethyl sulfoxide and γ-butyrolactone, a combination of dimethyl sulfoxide and γ-valerolactone, a combination of 3-methoxy-N,N-dimethylpropionamide and γ-butyrolactone, a combination of 3-methoxy-N,N-dimethylpropionamide, γ-butyrolactone and dimethyl sulfoxide, or a combination of N-methyl-2-pyrrolidone and ethyl lactate. An embodiment in which toluene is further added to these combined solvents in an amount of about 1 to 10% by mass based on the total mass of the solvent is also one of the preferred embodiments of the present invention.
In particular, from the viewpoint of storage stability of the resin composition, an embodiment containing γ-valerolactone as a solvent is one of the preferred embodiments of the present invention. In such an embodiment, the content of γ-valerolactone relative to the total mass of the solvent is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more. The upper limit of the content is not particularly limited and may be 100% by mass. The content may be determined in consideration of the solubility of components such as a specific resin contained in the resin composition, etc.
Furthermore, when dimethyl sulfoxide and γ-valerolactone are used in combination, the solvent preferably contains 60 to 90% by mass of γ-valerolactone and 10 to 40% by mass of dimethyl sulfoxide, more preferably 70 to 90% by mass of γ-valerolactone and 10 to 30% by mass of dimethyl sulfoxide, and even more preferably 75 to 85% by mass of γ-valerolactone and 15 to 25% by mass of dimethyl sulfoxide, relative to the total mass of the solvent.

From the viewpoint of coatability, the content of the solvent is preferably an amount that results in a total solids concentration of the resin composition of 5 to 80 mass%, more preferably an amount that results in a total solids concentration of 5 to 75 mass%, even more preferably an amount that results in a total solids concentration of 10 to 70 mass%, and even more preferably an amount that results in a total solids concentration of 20 to 70 mass%. The content of the solvent may be adjusted according to the desired thickness of the coating film and the coating method. When two or more types of solvents are contained, it is preferable that the total amount is within the above range.

<Metal adhesion improver>
The resin composition preferably contains a metal adhesion improver from the viewpoint of improving adhesion to metal materials used in electrodes, wiring, etc. Examples of the metal adhesion improver include a silane coupling agent having an alkoxysilyl group, an aluminum-based adhesion aid, a titanium-based adhesion aid, a compound having a sulfonamide structure, a compound having a thiourea structure, a phosphoric acid derivative compound, a β-ketoester compound, an amino compound, and the like.

〔Silane coupling agent〕
Examples of the silane coupling agent include the compounds described in paragraph 0316 of International Publication No. 2021/112189 and the compounds described in paragraphs 0067 to 0078 of JP-A-2018-173573, the contents of which are incorporated herein. In addition, it is also preferable to use two or more different silane coupling agents as described in paragraphs 0050 to 0058 of JP-A-2011-128358. It is also preferable to use the following compounds as the silane coupling agent. In the following formula, Me represents a methyl group, and Et represents an ethyl group. In addition, the following R includes a structure derived from a blocking agent in a blocked isocyanate group. The blocking agent may be selected according to the desorption temperature, and examples thereof include alcohol compounds, phenol compounds, pyrazole compounds, triazole compounds, lactam compounds, and active methylene compounds. For example, from the viewpoint of setting the desorption temperature at 160 to 180 ° C., caprolactam and the like are preferred. Commercially available products of such compounds include X-12-1293 (manufactured by Shin-Etsu Chemical Co., Ltd.).

Other silane coupling agents include, for example, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2- (aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, tris-(trimethoxysilylpropyl)isocyanurate, 3-ureidopropyltrialkoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-trimethoxysilylpropylsuccinic anhydride. These can be used alone or in combination of two or more.
Furthermore, an oligomer type compound having a plurality of alkoxysilyl groups can also be used as the silane coupling agent.
Examples of such oligomer-type compounds include compounds containing a repeating unit represented by the following formula (S-1).

In formula (S-1), R ^{1 S1} represents a monovalent organic group, R ^{1 S2} represents a hydrogen atom, a hydroxyl group or an alkoxy group, and n represents an integer of 0 to 2.
R ^S1 is preferably a structure containing a polymerizable group. Examples of the polymerizable group include a group having an ethylenically unsaturated bond, an epoxy group, an oxetanyl group, a benzoxazolyl group, a blocked isocyanate group, and an amino group. Examples of the group having an ethylenically unsaturated bond include a vinyl group, an allyl group, an isoallyl group, a 2-methylallyl group, a group having an aromatic ring directly bonded to a vinyl group (e.g., a vinylphenyl group), a (meth)acrylamide group, and a (meth)acryloyloxy group. Of these, a vinylphenyl group, a (meth)acrylamide group, or a (meth)acryloyloxy group is preferred, a vinylphenyl group or a (meth)acryloyloxy group is more preferred, and a (meth)acryloyloxy group is even more preferred.
R ^S2 is preferably an alkoxy group, more preferably a methoxy group or an ethoxy group.
n represents an integer of 0 to 2, and is preferably 1.
Here, the structures of the repeating units represented by formula (S-1) contained in the oligomer-type compound may be the same.
Here, among the multiple repeating units represented by formula (S-1) contained in the oligomer-type compound, it is preferable that n is 1 or 2 in at least one, more preferably that n is 1 or 2 in at least two, and further preferably that n is 1 in at least two.
As such oligomer type compounds, commercially available products can be used, and an example of a commercially available product is KR-513 (manufactured by Shin-Etsu Chemical Co., Ltd.).

[Aluminum-based adhesion promoter]
Examples of aluminum-based adhesion promoters include aluminum tris(ethylacetoacetate), aluminum tris(acetylacetonate), and ethylacetoacetate aluminum diisopropylate.

Other metal adhesion improvers that can be used include the compounds described in paragraphs 0046 to 0049 of JP 2014-186186 A and the sulfide-based compounds described in paragraphs 0032 to 0043 of JP 2013-072935 A, the contents of which are incorporated herein by reference.

The content of the metal adhesion improver is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 10 parts by mass, and even more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the polyimide precursor. By making the content equal to or greater than the above lower limit, the adhesion between the pattern and the metal layer will be good, and by making the content equal to or less than the above upper limit, the heat resistance and mechanical properties of the pattern will be good. Only one type of metal adhesion improver may be used, or two or more types may be used. When two or more types are used, it is preferable that the total is within the above range.

<Migration Inhibitor>
The resin composition preferably further contains a migration inhibitor. By containing the migration inhibitor, for example, when the resin composition is applied to a metal layer (or metal wiring) to form a film, migration of metal ions derived from the metal layer (or metal wiring) into the film can be effectively suppressed.

There are no particular limitations on the migration inhibitor, but examples include compounds having a heterocycle (pyrrole ring, furan ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring, pyrazole ring, isoxazole ring, isothiazole ring, tetrazole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, piperidine ring, piperazine ring, morpholine ring, 2H-pyran ring and 6H-pyran ring, triazine ring), thioureas and compounds having a sulfanyl group, hindered phenol compounds, salicylic acid derivative compounds, and hydrazide derivative compounds. In particular, triazole compounds such as 1,2,4-triazole, benzotriazole, 3-amino-1,2,4-triazole, and 3,5-diamino-1,2,4-triazole, and tetrazole compounds such as 1H-tetrazole, 5-phenyltetrazole, and 5-amino-1H-tetrazole are preferably used.

Among these, the resin composition preferably contains an azole compound.
From the viewpoint of suppressing the generation of voids in the cured product, the resin composition preferably contains an azole compound and a metal adhesion improver.
The azole compound is a compound containing an azole structure, and the azole structure refers to a five-membered ring structure containing a nitrogen atom as a ring member, and is preferably a five-membered ring structure containing two or more nitrogen atoms as ring members.Specific examples of the azole structure include an imidazole structure, a triazole structure, and a tetrazole structure.These structures may form a polycyclic ring by condensation with another ring structure, such as benzimidazole and benzotriazole.
As the compound having an azole structure, a compound in which a group represented by the following formula (R-1) or (R-2) is directly bonded to the azole structure is also preferred.

In formula (R-1), R ¹ represents a monovalent organic group, and * represents a bonding site with the azole structure.
In formula (R-2), R ² represents a hydrogen atom or a monovalent organic group, R ³ represents a monovalent organic group, and * represents a bonding site with the azole structure.
In formula (R-1), R ¹ is preferably a hydrocarbon group or a group represented by a bond between a hydrocarbon group and at least one group selected from the group consisting of -O-, -C(=O)-, -S-, -S(=O) ₂ - and -NR ^N -, where R ^N is as defined above.
The above-mentioned hydrocarbon group is preferably an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a group represented by a combination thereof.
The total number of carbon atoms in R ¹ is preferably 1 to 30, more preferably 2 to 25, and even more preferably 3 to 20.
The bonding site of R ¹ to the carbonyl group in formula (R-1) is preferably a hydrocarbon group or -NR ^N -.
In formula (R-1), * represents a bonding site to the azole structure, and is preferably a bonding site to a carbon atom that is a ring member of the azole structure.
In formula (R-2), R ² is preferably a hydrogen atom.
When ^R2 is a monovalent organic group, ^R2 is preferably a hydrocarbon group or a group represented by a bond between a hydrocarbon group and at least one group selected from the group consisting of -O-, -C(=O)-, -S-, -S(=O) ₂ - and -NR ^N -, where R ^N is as defined above.
The above-mentioned hydrocarbon group is preferably an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a group represented by a combination thereof.
When R ² is a monovalent organic group, the total number of carbon atoms is preferably 1 to 30, more preferably 2 to 25, and even more preferably 3 to 20.
When R ² is a monovalent organic group, the bonding site of R ² to the nitrogen atom in formula (R-2) is preferably a hydrocarbon group or -C(=O)-.
In formula (R-2), R ³ is preferably a hydrocarbon group or a group represented by a bond between a hydrocarbon group and at least one group selected from the group consisting of -O-, -C(=O)-, -S-, -S(=O) ₂ - and -NR ^N -, where R ^N is as defined above.
The above-mentioned hydrocarbon group is preferably an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or a group represented by a combination thereof.
When R ³ is a monovalent organic group, the total number of carbon atoms is preferably 1 to 30, more preferably 2 to 25, and even more preferably 3 to 20.
The bonding site of ^R3 to the nitrogen atom in formula (R-2) is preferably a hydrocarbon group or -C(=O)-.
In formula (R-2), * represents a bonding site to the azole structure, and is preferably a bonding site to a carbon atom that is a ring member of the azole structure.

As a migration inhibitor, an ion trapping agent that captures anions such as halogen ions can also be used.

Other migration inhibitors that can be used include the rust inhibitors described in paragraph 0094 of JP 2013-015701 A, the compounds described in paragraphs 0073 to 0076 of JP 2009-283711 A, the compounds described in paragraph 0052 of JP 2011-059656 A, the compounds described in paragraphs 0114, 0116, and 0118 of JP 2012-194520 A, and the compounds described in paragraph 0166 of WO 2015/199219 A, the contents of which are incorporated herein by reference.

Specific examples of migration inhibitors include the following compounds:

When the resin composition contains a migration inhibitor, the content of the migration inhibitor is preferably 0.01 to 5.0 mass %, more preferably 0.05 to 2.0 mass %, and even more preferably 0.1 to 1.0 mass %, based on the total solid content of the resin composition.

The migration inhibitor may be one type or two or more types. When two or more types of migration inhibitors are used, it is preferable that the total is within the above range.

<Light absorber>
The resin composition also preferably contains a compound (light absorber) whose absorbance at the exposure wavelength decreases upon exposure to light.

Whether or not a certain compound a contained in a resin composition corresponds to a light absorbent (that is, whether or not its absorbance at the exposure wavelength decreases upon exposure) can be determined by the following method.
First, a solution of compound a is prepared at the same concentration as that contained in the resin composition, and the molar absorption coefficient of compound a at the wavelength of the exposure light (mol ^-1 ·L·cm ^-1 , also called "molar absorption coefficient 1") is measured. The measurement is carried out quickly so as to reduce the influence of changes such as a decrease in the molar absorption coefficient of compound a. As the solvent for the solution, when the resin composition contains a solvent, that solvent is used, and when the resin composition does not contain a solvent, N-methyl-2-pyrrolidone is used.
Next, the solution of compound a is irradiated with exposure light, with the cumulative exposure dose being 500 mJ per mole of compound a.
Thereafter, the molar absorption coefficient (mol ⁻¹ ·L·cm ⁻¹ , also referred to as “molar absorption coefficient 2”) of compound a at the wavelength of the exposure light is measured using the solution of compound a after exposure.
From the above molar absorption coefficient 1 and molar absorption coefficient 2, the attenuation rate (%) is calculated based on the following formula. When the attenuation rate (%) is 5% or more, compound a is determined to be a compound whose absorbance at the exposure wavelength decreases upon exposure (i.e., a light absorber).
Extinction rate (%) = 1 - molar extinction coefficient 2 / molar extinction coefficient 1 x 100
The attenuation rate is preferably 10% or more, and more preferably 20% or more. There is no particular lower limit to the attenuation rate, so long as it is 0% or more.
When the resin composition is used to form a photosensitive film, the wavelength of the exposure light may be any wavelength that exposes the photosensitive film.
The wavelength of the exposure light is preferably a wavelength to which the photopolymerization initiator contained in the resin composition has sensitivity. The photopolymerization initiator has sensitivity to a certain wavelength, meaning that the photopolymerization initiator generates a polymerization initiating species when exposed to light of a certain wavelength.
The wavelength of the exposure light, in terms of its light source, may include (1) semiconductor laser (wavelengths 830 nm, 532 nm, 488 nm, 405 nm, 375 nm, 355 nm, etc.), (2) metal halide lamp, (3) high-pressure mercury lamp, g-line (wavelength 436 nm), h-line (wavelength 405 nm), i-line (wavelength 365 nm), broad (three wavelengths of g, h, and i-lines), (4) excimer laser, KrF excimer laser (wavelength 248 nm), ArF excimer laser (wavelength 193 nm), F2 excimer laser (wavelength 157 nm), (5) extreme ultraviolet light; EUV (wavelength 13.6 nm), (6) electron beam, and (7) second harmonic 532 nm and third harmonic 355 nm of YAG laser.
The wavelength of the exposure light may be selected from those to which the photopolymerization initiator has sensitivity, and preferably, h-line (wavelength 405 nm) or i-line (wavelength 365 nm), more preferably i-line (wavelength 365 nm).

The light absorbent may be a compound that generates radical polymerization initiating species upon exposure to light. However, from the viewpoints of resolution and chemical resistance, it is preferable that the light absorbent is a compound that does not generate radical polymerization initiating species upon exposure to light.
Whether or not a light absorbent is a compound that generates a radical polymerization initiating species upon exposure to light can be judged by the following method.
A solution containing a light absorber and a radical crosslinker at the same concentration as those contained in the resin composition is prepared. When the resin composition contains a radical crosslinker, the radical crosslinker in the solution is the same compound as the radical crosslinker contained in the resin composition and at the same concentration. When the resin composition does not contain a radical crosslinker, methyl methacrylate is used at a concentration five times that of the light absorber.
Thereafter, exposure light is irradiated to an integrated amount of 500 mJ.
After exposure, polymerization of the polymerizable compound is determined, for example, by high performance liquid chromatography, and if the ratio of the molar amount of the polymerized polymerizable compound to the total molar amount of the polymerizable compounds is 10% or less, the light absorber is determined to be a compound that does not generate radical polymerization initiating species upon exposure.
The molar ratio is preferably 5% or less, more preferably 3% or less. The lower limit of the molar ratio is not particularly limited, and may be 0%.
When the resin composition is used to form a photosensitive film, the wavelength of the exposure light may be any wavelength that exposes the photosensitive film.
The wavelength of the exposure light is preferably a wavelength to which the photopolymerization initiator contained in the resin composition has sensitivity.

Examples of the compound that generates a radical polymerization initiating species upon exposure include the same compounds as the above-mentioned photoradical polymerization initiator. When the composition contains a photoradical polymerization initiator as a light absorber, the compound that generates the radical species with the lowest polymerization initiation ability is the light absorber, and the rest are the photopolymerization initiators.
Examples of the compound that does not generate a radical polymerization initiating species upon exposure include a photoacid generator, a photobase generator, and a dye whose absorption wavelength changes upon exposure.
Among these, the light absorbent is preferably a naphthoquinone diazide compound or a dye whose absorbance changes upon exposure to light, and more preferably a naphthoquinone diazide compound.
As the light absorber, for example, a photoacid generator or a photobase generator may be used in combination with a compound whose absorbance at the exposure wavelength decreases depending on the pH.

[Naphthoquinone diazide compounds]
The naphthoquinone diazide compound includes a compound which generates indene carboxylic acid upon exposure and has a reduced absorbance at the exposure wavelength, and is preferably a compound having a 1,2-naphthoquinone diazide structure.
The use of a naphthoquinone diazide compound improves the resolution, but nitrogen is generated in the film upon exposure, which may cause voids in the cured product.
In the method for producing a cured product of the present invention, a decompression step is carried out, so that gases such as nitrogen generated from such compounds can be removed, and the generation of voids can be suppressed.
In this way, when a naphthoquinone diazide compound is used in the method for producing a cured product of the present invention, it is possible to achieve both the effect of improving resolution and the effect of suppressing the occurrence of voids.
The naphthoquinone diazide compound is preferably a naphthoquinone diazide sulfonic acid ester of a hydroxy compound.
The hydroxy compound is preferably a compound represented by any one of the following formulas (H1) to (H6).

In formula (H1), ^R1 and ^R2 each independently represent a monovalent organic group, ^R3 and ^R4 each independently represent a hydrogen atom or a monovalent organic group, n1, n2, m1, and m2 each independently represent an integer of 0 to 5, and at least one of m1 and m2 is an integer of 1 to 5.
In formula (H2), Z represents a tetravalent organic group; L ¹ , L ² , L ³ and L ⁴ each independently represent a single bond or a divalent organic group; R ⁵ , R ⁶ , R ⁷ and R ⁸ each independently represent a monovalent organic group; n3, n4, n5 and n6 each independently represent an integer from 0 to 3; m3, m4, m5 and m6 each independently represent an integer from 0 to 2; and at least one of m3, m4, m5 and m6 is 1 or 2.
In formula (H3), R ⁹ and R ¹⁰ each independently represent a hydrogen atom or a monovalent organic group; L ⁵ each independently represent a divalent organic group; and n7 represents an integer of 3 to 8.
In formula (H4), ^L6 represents a divalent organic group, and ^L7 and ^L8 each independently represent a divalent organic group containing an aliphatic tertiary or quaternary carbon.
In formula (H5), R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ¹⁹ and R ²⁰ each independently represent a hydrogen atom, a halogen atom or a monovalent organic group; L ⁹ , L ¹⁰ and L ¹¹ each independently represent a single bond or a divalent organic group; m7, m8, m9 and m10 each independently represent an integer of 0 to 2, and at least one of m7, m8, m9 and m10 is 1 or 2.
In formula (H6), R ⁴² , R ⁴³ , R ⁴⁴ , and R ⁴⁵ each independently represent a hydrogen atom or a monovalent organic group, R ⁴⁶ and R ⁴⁷ each independently represent a monovalent organic group, n16 and n17 each independently represent an integer of 0 to 4, m11 and m12 each independently represent an integer of 0 to 4, and at least one of m11 and m12 is an integer of 1 to 4.

In formula (H1), ^R1 and ^R2 are each preferably independently a monovalent organic group having 1 to 60 carbon atoms, and more preferably a monovalent organic group having 1 to 30 carbon atoms. Examples of the monovalent organic group in ^R1 and ^R2 include a hydrocarbon group which may have a substituent, such as an aromatic hydrocarbon group which may have a substituent such as a hydroxy group.
In formula (H1), ^R3 and ^R4 are each preferably independently a monovalent organic group having 1 to 60 carbon atoms, and more preferably a monovalent organic group having 1 to 30 carbon atoms. Examples of the monovalent organic group in ^R3 and ^R4 include hydrocarbon groups which may have a substituent, such as a hydroxyl group or the like.
In formula (H1), n1 and n2 each independently are preferably 0 or 1, and more preferably 0.
In formula (H1), it is preferable that both m1 and m2 are 1.

The compound represented by formula (H1) is preferably a compound represented by any one of formulas (H1-1) to (H1-5).

In formula (H1-1), R ²¹ , R ²² and R ²³ each independently represent a hydrogen atom or a monovalent organic group, preferably a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and more preferably a hydrogen atom or a group represented by the following formula (R-1):

In formula (R-1), R ²⁹ represents a hydrogen atom, an alkyl group or an alkoxy group, n13 represents an integer of 0 to 2, and * represents a bonding site to another structure.
In (H1-1), n8, n9 and n10 each independently represent an integer of 0 to 2, and preferably 0 or 1.

In formula (H1-2), R ²⁴ represents a hydrogen atom or a monovalent organic group, and is preferably a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an alkoxy group having 1 to 20 carbon atoms. n14, n15, and n16 each independently represent an integer of 0 to 2. R ³⁰ represents a hydrogen atom or an alkyl group.

In formula (H1-3), R ²⁵ , R ²⁶ , R ²⁷ and R ²⁸ each independently represent a monovalent organic group, and are preferably a hydrogen atom, an alkyl group or a group represented by the above formula (R-1).
In formula (H1-3), n11, n12 and n13 each independently represent an integer of 0 to 2, and preferably 0 or 1.

The compound represented by formula (H1-1) is preferably a compound represented by any one of the following formulas (H1-1-1) to (H1-1-4).
The compound represented by formula (H1-2) is preferably a compound represented by the following formula (H1-2-1) or (H1-2-2).
The compound represented by formula (H1-3) is preferably a compound represented by the following formulas (H1-3-1) to (H1-3-3).

In formula (H2), Z is preferably a tetravalent group having 1 to 20 carbon atoms, and more preferably a group represented by any one of the following formulae (Z-1) to (Z-4): In the following formulae (Z-1) to (Z-4), * represents a bonding site to other structures.

In formula (H2), it is preferable that L ¹ , L ² , L ³ and L ⁴ each independently represent a single bond or a methylene group.
In formula (H2), R ⁵ , R ⁶ , R ⁷ and R ⁸ are preferably each independently an organic group having 1 to 30 carbon atoms.
In formula (H2), n3, n4, n5 and n6 each independently represent an integer of 0 to 2, and more preferably 0 or 1.
In formula (H2), m3, m4, m5 and m6 each independently preferably represent 1 or 2, and more preferably represent 1.
Examples of the compound represented by formula (H2) include compounds having the following structures:

In formula (H3), it is preferable that R ⁹ and R ¹⁰ each independently represent a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms.
In formula (H3), it is preferable that each ^L5 independently represents a group represented by the following formula (L-1).

In formula (L-1), R ³⁰ represents a monovalent organic group having 1 to 20 carbon atoms, n14 represents an integer of 1 to 5, and * represents a bonding site to another structure.
In formula (H3), n7 is preferably an integer of 4 to 6.
Examples of the compound represented by formula (H3) include the following compounds: In the following formula, each n independently represents an integer of 0 to 9.

In formula (H4), L ⁶ is preferably —C(CF ₃ ) ₂ —, —S(═O) ₂ — or —C(═O)—.
In formula (H4), L ⁷ and L ⁸ are preferably each independently a divalent organic group having 2 to 20 carbon atoms.
Examples of the compound represented by formula (H4) include the following compounds.

In formula (H5), ^R11 , ^R12 , ^R13 , ^R14 , ^R15 , ^R16 , ^R17 , ^R18 , ^R19 and ^R20 are each preferably independently a hydrogen atom, a halogen atom, an alkyl group, an alkenyl group, an alkoxy group, an allyl group or an acyl group.
In formula (H5), L ⁹ , L ¹⁰ and L ¹¹ each independently represent preferably a single bond, -O-, -S-, -S(═O) ₂ -, -C(═O)-, -C(═O)O-, cyclopentylidene, cyclohexylidene, phenylene or a divalent organic group having 1 to 20 carbon atoms, and more preferably a group represented by any of the following formulae (L-2) to (L-4).

In formulas (L-2) to (L-4), R ³¹ and R ³² each independently represent a hydrogen atom, an alkyl group, an alkenyl group, or an aryl group; R ³⁴ , R ³⁵ , R ³⁶ , and R ³⁷ each independently represent a hydrogen atom or an alkyl group; n15 is an integer of 1 to 5; R ³⁸ , R ³⁹ , R ⁴⁰ , and R ⁴¹ each independently represent a hydrogen atom or an alkyl group; and * represents a bonding site to another structure.
Examples of the compound represented by formula (H5) include the following compounds.

In formula (H6), R ⁴² , R ⁴³ , R ⁴⁴ , and R ⁴⁵ each independently represent a hydrogen atom or a monovalent organic group, preferably a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, and more preferably an alkyl group having 1 to 4 carbon atoms.
In formula (H6), R ⁴⁶ and R ⁴⁷ each independently preferably represent an alkyl group, an alkoxy group or an aryl group, and more preferably an alkyl group.
In formula (H6), n16 and n17 each independently represent preferably an integer of 0 to 2, and more preferably 0 or 1.
In formula (H6), n16 and n17 each independently represent preferably an integer of 1 to 3, and more preferably 2 or 3.
Examples of the compound represented by formula (H6) include the following compounds.

Other examples of hydroxy compounds include polyhydroxybenzophenones such as 2,3,4-trihydroxybenzophenone, 2,4,4'-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone, 2,3,4-trihydroxy-2'-methylbenzophenone, 2,3,4,4'-tetrahydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,4,6,3',4'-pentahydroxybenzophenone, 2,3,4,2',4'-pentahydroxybenzophenone, 2,3,4,2',5'-pentahydroxybenzophenone, 2,4,6,3',4',5'-hexahydroxybenzophenone, and 2,3,4,3',4',5'-hexahydroxybenzophenone;
polyhydroxyphenyl alkyl ketones such as 2,3,4-trihydroxyacetophenone, 2,3,4-trihydroxyphenyl pentyl ketone, and 2,3,4-trihydroxyphenyl hexyl ketone;
bis((poly)hydroxyphenyl)alkanes such as bis(2,4-dihydroxyphenyl)methane, bis(2,3,4-trihydroxyphenyl)methane, bis(2,4-dihydroxyphenyl)propane-1, bis(2,3,4-trihydroxyphenyl)propane-1, nordihydroguaiaretic acid, and 1,1-bis(4-hydroxyphenyl)cyclohexane;
Polyhydroxybenzoic acid esters such as propyl 3,4,5-trihydroxybenzoate, phenyl 2,3,4-trihydroxybenzoate, and phenyl 3,4,5-trihydroxybenzoate;
bis(polyhydroxybenzoyl)alkanes or bis(polyhydroxybenzoyl)aryls such as bis(2,3,4-trihydroxybenzoyl)methane, bis(3-acetyl-4,5,6-trihydroxyphenyl)methane, bis(2,3,4-trihydroxybenzoyl)benzene, and bis(2,4,6-trihydroxybenzoyl)benzene;
Alkylene di(polyhydroxybenzoates) such as ethylene glycol di(3,5-dihydroxybenzoate) and ethylene glycol di(3,4,5-trihydroxybenzoate);
polyhydroxybiphenyls such as 2,3,4-biphenyltriol, 3,4,5-biphenyltriol, 3,5,3',5'-biphenyltetrol, 2,4,2',4'-biphenyltetrol, 2,4,6,3',5'-biphenylpentol, 2,4,6,2',4',6'-biphenylhexol, and 2,3,4,2',3',4'-biphenylhexol;
bis(polyhydroxy)sulfides such as 4,4'-thiobis(1,3-dihydroxy)benzene;
bis(polyhydroxyphenyl)ethers such as 2,2',4,4'-tetrahydroxydiphenyl ether;
bis(polyhydroxyphenyl)sulfoxides such as 2,2',4,4'-tetrahydroxydiphenylsulfoxide;
bis(polyhydroxyphenyl)sulfones such as 2,2',4,4'-diphenylsulfone,
Tris(4-hydroxyphenyl)methane, 4,4',4"-trihydroxy-3,5,3',5'-tetramethyltriphenylmethane, 4,4',3",4"-tetrahydroxy-3,5,3',5'-tetramethyltriphenylmethane, 4-[bis(3,5-dimethyl-4-hydroxyphenyl)methyl]-2-methoxy-phenol, 4,4'-(3,4-diol-benzylidene)bis[2,6-dimethylphenol], 4,4'-[(2-hydroxy-phenyl)methylene]bis[2-cyclohexyl-5-methylphenol], 4,4',2",3",4"-pentahydroxy-3,5,3',5' -tetramethyltriphenylmethane, 2,3,4,2',3',4'-hexahydroxy-5,5'-diacetyltriphenylmethane, 2,3,4,2',3',4',3",4"-octahydroxy-5,5'-diacetyltriphenylmethane, 2,4,6,2',4',6'-hexahydroxy-5,5'-dipropionyltriphenylmethane and other polyhydroxytriphenylmethanes; 4,4'-(phenylmethylene)bisphenol, 4,4'-(1-phenyl-ethylidene)bis[2-methylphenol], 4,4',4"-ethylidene-trisphenol and other polyhydroxytriphenylethanes;
Polyhydroxy spirobyindanes such as 3,3,3',3'-tetramethyl-1,1'-spirobi-indan-5,6,5',6'-tetrol, 3,3,3',3'-tetramethyl-1,1'-spirobi-indan-5,6,7,5',6',7'-hexol, 3,3,3',3'-tetramethyl-1,1'-spirobi-indan-4,5,6,4',5',6'-hexol, and 3,3,3',3'-tetramethyl-1,1'-spirobi-indan-4,5,6,5',6',7'-hexool; polyhydroxy flavans such as 2,4,4-trimethyl-2',4',7'-trihydroxy flavan;
Polyhydroxyphthalides such as 3,3-bis(3,4-dihydroxyphenyl)phthalide, 3,3-bis(2,3,4-trihydroxyphenyl)phthalide, and 3',4',5',6'-tetrahydroxyspiro[phthalide-3,9'-xanthene]; flavonoid pigments such as morin, quercetin, and rutin;
α,α',α"-tris(4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α"-tris(3,5-dimethyl-4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α"-tris(3,5-diethyl-4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α"-tris(3,5-di-n-propyl-4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α"-tris(3,5-diisopropyl-4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α"-tris(3,5-di-n-butyl-4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α" -Tris(3-methyl-4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α"-tris(3-methoxy-4-hydroxyphenyl)1,3,5-triisopropylbenzene, α,α',α"-tris(2,4-dihydroxyphenyl)1,3,5-triisopropylbenzene, 1,3,5-tris(3,5-dimethyl-4-hydroxyphenyl)benzene, 1,3,5-tris(5-methyl-2-hydroxyphenyl)benzene, 2,4,6-tris(3,5-dimethyl-4-hydroxyphenylthiomethyl)mesitylene, 1-[α-methyl-α-(4'-hydroxyphenyl)ethyl]-4-[α,α'-bis(4"-hydroxyphenyl)ethyl]benzene, 1-[α-methyl 1-[α-methyl-α-(3',5'-dimethyl-4'-hydroxyphenyl)ethyl]-4-[α,α'-bis(3",5"-dimethyl-4"-hydroxyphenyl)ethyl]benzene, 1-[α-methyl(3'-methyl-4'-hydroxyphenyl)ethyl]-4-[α',α'-bis(3"-methyl-4"-hydroxyphenyl)ethyl]benzene, 1-[α-methyl-α-(3'-methoxy-4'-hydroxyphenyl)ethyl]-4-[α',α'-bis(3"-methoxy-4"-hydroxyphenyl)ethyl]benzene, 1-[α-methyl-α-(2',4'-dihydroxyphenyl)ethyl]-4-[α',α'-bis(3"-methoxy-4"-hydroxyphenyl)ethyl]benzene, polyhydroxy compounds described in JP-A-4-253058, such as α,α,α',α',α",α"-hexakis-(4-hydroxyphenyl)-1,3,5-triethylbenzene; poly(hydroxyphenyl)alkanes described in JP-A-5-303200 and EP-530148, such as 1,2,2,3-tetra(p-hydroxyphenyl)propane and 1,3,3,5-tetra(p-hydroxyphenyl)pentane;
p-bis(2,3,4-trihydroxybenzoyl)benzene, p-bis(2,4,6-trihydroxybenzoyl)benzene, m-bis(2,3,4-trihydroxybenzoyl)benzene, m-bis(2,4,6-trihydroxybenzoyl)benzene, p-bis(2,5-dihydroxy-3-bromobenzoyl)benzene, p-bis(2,3,4-trihydroxy-5-methylbenzoyl)benzene, p-bis(2,3,4-trihydroxy-5-methoxybenzoyl)benzene, p-bis(2,3,4-trihydroxy-5-nitrobenzoyl)benzene, p-bis(2,3,4- trihydroxy-5-cyanobenzoyl)benzene, 1,3,5-tris(2,5-dihydroxybenzoyl)benzene, 1,3,5-tris(2,3,4-trihydroxybenzoyl)benzene, 1,2,3-tris(2,3,4-trihydroxybenzoyl)benzene, 1,2,4-tris(2,3,4-trihydroxybenzoyl)benzene, 1,2,4,5-tetrakis(2,3,4-trihydroxybenzoyl)benzene, α,α'-bis(2,3,4-trihydroxybenzoyl)p-xylene, α,α',α'-tris(2,3,4-trihydroxybenzoyl)mesylene,
2,6-bis-(2-hydroxy-3,5-dimethylbenzyl)-p-cresol, 2,6-bis-(2-hydroxy-5'-methylbenzyl)-p-cresol, 2,6-bis-(2,4,6-trihydroxybenzyl)-p-cresol, 2,6-bis-(2,3,4-trihydroxybenzyl)-p-cresol, 2,6-bis-(2,3,4-trihydroxybenzyl)-3,5-dimethyl-phenol, 4,6-bis-(4-hydroxy-3,5-dimethylbenzyl)-pyrogallol, 2,6-bis-(4 -hydroxy-3,5-dimethylbenzyl)-1,3,4-trihydroxy-phenol, 4,6-bis-(2,4,6-trihydroxybenzyl)-2,4-dimethyl-phenol, 4,6-bis-(2,3,4-trihydroxybenzyl)-2,5-dimethyl-phenol, 2,6-bis-(4-hydroxybenzyl)-p-cresol, 2,6-bis(4-hydroxybenzyl)-4-cyclohexylphenol, 2,6-bis(4-hydroxy-3-methylbenzyl)-p-cresol, 2,6-bis(4- 2,6-bis(4-hydroxy-2,5-dimethylbenzyl)-p-cresol, 2,6-bis(4-hydroxy-3-methylbenzyl)-4-phenyl-phenol, 2,2',6,6'-tetrakis[(4-hydroxyphenyl)methyl]-4,4'-methylenediphenol, 2,2',6,6'-tetrakis[(4-hydroxy-3,5-dimethylphenyl)methyl]-4,4'-methylenediphenol, 2,2',6,6'-tetrakis[(4 -hydroxy-3-methylphenyl)methyl]-4,4'-methylenediphenol, 2,2'-bis[(4-hydroxy-3,5-dimethylphenyl)methyl]6,6'-dimethyl-4,4'-methylenediphenol, 2,2',3,3'-tetrahydro-3,3,3',3'-tetramethyl-1,1'-spirobi(1H-indene)-5,5',6,6',7,7'hexanol, bis(4-hydroxy-3,5-dimethylphenyl)-(4-hydroxy-3-methoxyphenyl)methane, and the like can be mentioned.
Furthermore, a low molecular weight phenol resin such as a novolak resin can also be used.

Naphthoquinone diazide sulfonic acids include 6-diazo 5,6-dihydro-5-oxo-1-naphthalene sulfonic acid, 1,2-naphthoquinone-(2)-diazo-5-sulfonic acid, etc., which may be used in combination.

The method for producing a naphthoquinone diazide sulfonate ester of a hydroxy compound is not particularly limited. For example, the ester can be obtained by converting naphthoquinone diazide sulfonic acid into a sulfonyl chloride with chlorosulfonic acid or thionyl chloride, and then subjecting the resulting naphthoquinone diazide sulfonyl chloride to a condensation reaction with the hydroxy compound.
For example, a hydroxy compound and a predetermined amount of naphthoquinone diazide sulfonyl chloride are reacted in a solvent such as dioxane, acetone, or tetrahydrofuran in the presence of a basic catalyst such as triethylamine to carry out esterification, and the resulting product is washed with water and dried to obtain the compound.

The esterification rate of the naphthoquinone diazide sulfonic acid ester is not particularly limited, but is preferably 10% or more, and more preferably 20% or more. The upper limit of the esterification rate is not particularly limited, and may be 100%.
The above-mentioned esterification rate can be confirmed by ¹ H-NMR or the like as the proportion of esterified groups among the hydroxy groups contained in the hydroxy compound.

In addition, the compounds described in paragraphs 0088 to 0108 of JP 2019-206689 A can also be used as light absorbents.

The amount of the light absorber relative to the total solid content of the resin composition is not particularly limited, but is preferably 0.1 to 20% by mass, more preferably 0.5 to 10% by mass, and even more preferably 1 to 5% by mass.

<Polymerization inhibitor>
The resin composition preferably contains a polymerization inhibitor, such as a phenolic compound, a quinone compound, an amino compound, an N-oxyl free radical compound, a nitro compound, a nitroso compound, a heteroaromatic ring compound, or a metal compound.

Specific examples of the polymerization inhibitor include the compounds described in paragraph 0310 of WO 2021/112189, p-hydroquinone, o-hydroquinone, 4-hydroxy-2,2,6,6-tetramethylpiperidine 1-oxyl free radical, phenoxazine, 1,4,4-trimethyl-2,3-diazabicyclo[3.2.2]non-2-ene-N,N-dioxide, etc. The contents of which are incorporated herein by reference.
It is also preferable to use the following compounds as a polymerization inhibitor.

When the resin composition contains a polymerization inhibitor, the content of the polymerization inhibitor is preferably 0.01 to 20 mass % relative to the total solid content of the resin composition, more preferably 0.02 to 15 mass %, and even more preferably 0.05 to 10 mass %.

The polymerization inhibitor may be one type or two or more types. When two or more types of polymerization inhibitors are used, it is preferable that the total is within the above range.

<Other additives>
The resin composition may contain various additives, such as surfactants, higher fatty acid derivatives, thermal polymerization initiators, inorganic particles, ultraviolet absorbers, organometallic complexes, antioxidants, aggregation inhibitors, phenolic compounds, other polymer compounds, plasticizers, and other auxiliaries (e.g., defoamers, flame retardants, etc.), as necessary, within the scope of the effects of the present invention. By appropriately incorporating these components, it is possible to adjust the properties of the film, etc. These components can be referred to, for example, in paragraphs 0183 and after of JP-A-2012-003225 (corresponding to paragraph 0237 of US Patent Application Publication No. 2013/0034812), and in paragraphs 0101 to 0104, 0107 to 0109, etc. of JP-A-2008-250074, the contents of which are incorporated herein. When these additives are blended, the total content is preferably 3% by mass or less of the solid content of the resin composition.

[Inorganic particles]
Specific examples of inorganic particles include calcium carbonate, calcium phosphate, silica, kaolin, talc, titanium dioxide, alumina, barium sulfate, calcium fluoride, lithium fluoride, zeolite, molybdenum sulfide, and glass.

The average particle size of the inorganic particles is preferably from 0.01 to 2.0 μm, more preferably from 0.02 to 1.5 μm, even more preferably from 0.03 to 1.0 μm, and particularly preferably from 0.04 to 0.5 μm.
The above average particle size of the inorganic particles is the primary particle size and also the volume average particle size. The volume average particle size can be measured by a dynamic light scattering method using, for example, a Nanotrac WAVE II EX-150 (manufactured by Nikkiso Co., Ltd.).
When the above measurements are difficult, the measurements can also be made by centrifugal sedimentation light transmission method, X-ray transmission method, or laser diffraction/scattering method.

[Organometallic Complexes]
The resin composition also preferably contains an organometallic complex containing at least one metal atom selected from titanium, zirconium, and hafnium.
The organometallic complex preferably contains a compound represented by the following formula (T-1).

In formula (T-1), M is titanium, zirconium, or hafnium, l1 is an integer of 0 to 2, l2 is 0 or 1, l1+l2×2 is an integer of 0 to 2, m is an integer of 0 to 4, n is an integer of 0 to 2, and l1+l2+m+n×2=4, R ¹¹ is independently a substituted or unsubstituted cyclopentadienyl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted phenoxy group, R ¹² is a substituted or unsubstituted hydrocarbon group, R ² is independently a group containing a structure represented by formula (T-2) below, R ³ is independently a group containing a structure represented by formula (T-2) below, and X ^A is independently an oxygen atom or a sulfur atom.

In formula (T-2), X ¹ to X ³ each independently represent -C(-*)= or -N=, * represents a bonding site to another structure, and # represents a bonding site to a metal atom.

In formula (T-1), from the viewpoint of storage stability of the composition, M is preferably titanium.
In formula (T-1), an embodiment in which l1 and l2 are 0 is also one of the preferred embodiments of the present invention.
In formula (T-1), m is preferably 2 or 4, and more preferably 2.
In formula (T-1), n is preferably 1 or 2, and more preferably 1.
Here, it is also preferred that l1 and l2 are 0, and m is 0, 2 or 4 in formula (T-1).

In formula (T-1), from the viewpoint of the stability of the organometallic complex, R ¹¹ is preferably a substituted or unsubstituted cyclopentadienyl ligand.
In addition, the cyclopentadienyl group, alkoxy group and phenoxy group in R ¹¹ may be substituted, but the unsubstituted embodiment is also one of the preferred embodiments of the present invention.

In formula (T-1), R ¹² is preferably a hydrocarbon group having 1 to 20 carbon atoms, and more preferably a hydrocarbon group having 2 to 10 carbon atoms.
The hydrocarbon group for R ¹² may be either an aliphatic hydrocarbon group or an aromatic hydrocarbon group, with an aromatic hydrocarbon group being preferred.
The aliphatic hydrocarbon group may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group, with a saturated aliphatic hydrocarbon group being preferred.
The aromatic hydrocarbon group is preferably an aromatic hydrocarbon group having 6 to 20 carbon atoms, more preferably an aromatic hydrocarbon group having 6 to 10 carbon atoms, and even more preferably a phenylene group.
The substituent in R ¹² is preferably a monovalent substituent, such as a halogen atom, etc. When R ¹² is an aromatic hydrocarbon group, it may have an alkyl group as a substituent.
Among these, in formula (T-1), R ¹² is preferably an unsubstituted phenylene group, and the phenylene group in R ¹² is preferably a 1,2-phenylene group.

In formula (T-1), when m is 2 or more and two or more R ^2s are included, the structures of the two or more R ^2s may be the same or different.
In formula (T-1), when n is 2 or more and two or more R ^3s are included, the structures of the two or more R ^3s may be the same or different.

In formula (T-2), X ¹ to X ³ each independently represent -C(-*)= or -N=, preferably at least one represents -C(-*)=, and more preferably at least two represent -C(-*)=.

Specific examples of compounds represented by formula (T-1) include compounds I-5 to I-8 in the examples, but are not limited to these.

The resin composition may also contain other organotitanium compounds. By containing other organotitanium compounds, a resin layer with excellent chemical resistance can be formed even when cured at low temperatures.

Usable organic titanium compounds include those in which an organic group is bonded to a titanium atom via a covalent bond or an ionic bond.
Specific examples of the organotitanium compound are shown below in I) to VII):
I) Titanium chelate compounds: Titanium chelate compounds having two or more alkoxy groups are more preferred because they provide a resin composition with good storage stability and a good curing pattern. Specific examples include titanium bis(triethanolamine) diisopropoxide, titanium di(n-butoxide) bis(2,4-pentanedionate), titanium diisopropoxide bis(2,4-pentanedionate), titanium diisopropoxide bis(tetramethylheptanedionate), titanium diisopropoxide bis(ethylacetoacetate), etc.
II) Tetraalkoxytitanium compounds: For example, titanium tetra(n-butoxide), titanium tetraethoxide, titanium tetra(2-ethylhexoxide), titanium tetraisobutoxide, titanium tetraisopropoxide, titanium tetramethoxide, titanium tetramethoxypropoxide, titanium tetramethylphenoxide, titanium tetra(n-nonyloxide), titanium tetra(n-propoxide), titanium tetrastearyloxide, titanium tetrakis[bis{2,2-(allyloxymethyl)butoxide}], and the like.
III) Titanocene compounds: For example, pentamethylcyclopentadienyltitanium trimethoxide, bis(η5-2,4-cyclopentadiene-1-yl)bis(2,6-difluorophenyl)titanium, bis(η5-2,4-cyclopentadiene-1-yl)bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium, and the like.
IV) Monoalkoxytitanium compounds: For example, titanium tris(dioctylphosphate) isopropoxide, titanium tris(dodecylbenzenesulfonate) isopropoxide, etc.
V) Titanium oxide compounds: For example, titanium oxide bis(pentanedionate), titanium oxide bis(tetramethylheptanedionate), phthalocyanine titanium oxide, and the like.
VI) Titanium tetraacetylacetonate compounds: For example, titanium tetraacetylacetonate.
VII) Titanate coupling agents: for example, isopropyl tridodecylbenzenesulfonyl titanate.

Among these, from the viewpoint of better chemical resistance, the organic titanium compound is preferably at least one compound selected from the group consisting of I) titanium chelate compounds, II) tetraalkoxytitanium compounds, and III) titanocene compounds. In particular, titanium diisopropoxide bis(ethylacetoacetate), titanium tetra(n-butoxide), and bis(η5-2,4-cyclopentadiene-1-yl)bis(2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl)titanium are preferred.

When an organometallic complex is contained, the content thereof is preferably 0.05 to 10 parts by mass, and more preferably 0.1 to 2 parts by mass, relative to 100 parts by mass of the polyimide precursor. When the content is 0.05 part by mass or more, the heat resistance and chemical resistance of the obtained cured pattern are improved, and when it is 10 parts by mass or less, the storage stability of the composition is superior.
These other additives include the compounds described in paragraphs 0316 to 0358 of WO 2022/145355, the disclosures of which are incorporated herein by reference.

<Characteristics of Resin Composition>
The viscosity of the resin composition can be adjusted by the solid content concentration of the resin composition. From the viewpoint of the coating film thickness, 1,000 mm ² /s to 12,000 mm ² /s is preferable, 2,000 mm ² /s to 10,000 mm ² /s is more preferable, and 2,500 mm ² /s to 8,000 mm ² /s is even more preferable. If it is within the above range, it is easy to obtain a coating film with high uniformity. If it is 1,000 mm ² /s or more, it is easy to apply it with a film thickness required for, for example, a rewiring insulating film, and if it is 12,000 mm ² /s or less, a coating film with excellent coating surface condition is obtained.

<Restrictions on substances contained in resin composition>
The water content of the resin composition is preferably less than 2.0% by mass, more preferably less than 1.5% by mass, and even more preferably less than 1.0% by mass. If the water content is less than 2.0%, the storage stability of the resin composition is improved.
Methods for maintaining the moisture content include adjusting the humidity during storage and reducing the porosity of the container during storage.

From the viewpoint of insulation, the metal content of the resin composition is preferably less than 5 ppm by mass (parts per million), more preferably less than 1 ppm by mass, and even more preferably less than 0.5 ppm by mass. Examples of metals include sodium, potassium, magnesium, calcium, iron, copper, chromium, nickel, etc., but metals contained as complexes of organic compounds and metals are excluded. When multiple metals are contained, it is preferable that the total of these metals is within the above range.

In addition, methods for reducing metal impurities unintentionally contained in the resin composition include selecting raw materials with a low metal content as the raw materials constituting the resin composition, filtering the raw materials constituting the resin composition, and lining the inside of the apparatus with polytetrafluoroethylene or the like to perform distillation under conditions that minimize contamination as much as possible.

Considering the use of the resin composition as a semiconductor material, the content of halogen atoms is preferably less than 500 mass ppm, more preferably less than 300 mass ppm, and even more preferably less than 200 mass ppm from the viewpoint of wiring corrosion. Among them, those present in the form of halogen ions are preferably less than 5 mass ppm, more preferably less than 1 mass ppm, and even more preferably less than 0.5 mass ppm. Examples of halogen atoms include chlorine atoms and bromine atoms. It is preferable that the total of chlorine atoms and bromine atoms, or chlorine ions and bromine ions, is within the above range.
A preferred method for adjusting the content of halogen atoms is ion exchange treatment.

A conventionally known container can be used as the container for the resin composition. As the container, it is also preferable to use a multi-layer bottle whose inner wall is made of six types of six layers of resin, or a bottle with a seven-layer structure of six types of resin, in order to prevent impurities from being mixed into the raw materials or the resin composition. An example of such a container is the container described in JP 2015-123351 A.

<Cured Product of Resin Composition>
By using the resin composition in the method for producing a cured product of the present invention, a cured product of the resin composition can be obtained.
The cured product of the present invention is a cured product obtained by the method for producing a cured product of the present invention.
The form of the cured product is not particularly limited, and may be selected according to the application, such as a film, a rod, a sphere, or a pellet. In the present invention, the cured product is preferably a film. By pattern processing using the above-mentioned exposure step and development step, the shape of the cured product can be selected according to the application, such as forming a protective film on the wall surface, forming a via hole for electrical conduction, adjusting impedance, electrostatic capacitance, or internal stress, and imparting a heat dissipation function. The film thickness of the cured product (film made of the cured product) is preferably 0.5 μm or more and 150 μm or less.
The shrinkage percentage when the resin composition is cured is preferably 50% or less, more preferably 45% or less, and even more preferably 40% or less. Here, the shrinkage percentage refers to the percentage of the volume change before and after curing of the resin composition, and can be calculated by the following formula.
Shrinkage rate [%] = 100 - (volume after curing ÷ volume before curing) x 100

<Characteristics of the cured product of the resin composition>
The imidization reaction rate of the polyimide in the cured product is preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. If it is 70% or more, the cured product may have excellent mechanical properties.
The breaking elongation of the cured product is preferably 30% or more, more preferably 40% or more, and even more preferably 50% or more.
The glass transition temperature (Tg) of the cured product is preferably 180° C. or higher, more preferably 210° C. or higher, and even more preferably 230° C. or higher.

The linear thermal expansion coefficient of the cured product in the range of 25° C. to 125° C. is preferably 65 ppm/K or less, more preferably 60 ppm/K or less, and even more preferably 55 ppm/K or less. There is no particular lower limit for the linear thermal expansion coefficient, and it is preferably 0 ppm/K or less.
The linear thermal expansion coefficient can be measured using a known thermomechanical analyzer such as TMA8310 manufactured by Rigaku Corporation in accordance with JIS K 7197:2012.

The tensile modulus of the cured product at 25° C. is preferably 2.5 GPa or more, more preferably 2.8 GPa or more, and even more preferably 3.0 GPa or more.
The upper limit of the tensile modulus is not particularly limited, but is preferably 7.0 GPa or less.
The tensile modulus can be measured, for example, according to JIS K 7161-1:2014.

The tensile elongation of the cured product at 25° C. is preferably 30% or more, more preferably 35% or more, and even more preferably 40% or more.
The upper limit of the tensile elongation is not particularly limited, but is preferably 200% or less.
The tensile elongation can be measured, for example, according to JIS K 7161-1:2014.

<Preparation of Resin Composition>
The resin composition can be prepared by mixing the above-mentioned components. The mixing method is not particularly limited, and can be a conventionally known method.
Examples of the mixing method include mixing with a stirring blade, mixing with a ball mill, and mixing by rotating a tank.
The temperature during mixing is preferably from 10 to 30°C, more preferably from 15 to 25°C.

It is preferable to perform filtration using a filter in order to remove foreign matter such as dust and fine particles in the resin composition. The filter pore size is, for example, preferably 5 μm or less, more preferably 1 μm or less, even more preferably 0.5 μm or less, and even more preferably 0.1 μm or less. The material of the filter is preferably polytetrafluoroethylene, polyethylene, or nylon. When the material of the filter is polyethylene, it is more preferable that it is HDPE (high density polyethylene). The filter may be used after being washed in advance with an organic solvent. In the filter filtration process, multiple types of filters may be connected in series or in parallel. When multiple types of filters are used, filters with different pore sizes or materials may be used in combination. As an example of a connection mode, an HDPE filter with a pore size of 1 μm as the first stage and an HDPE filter with a pore size of 0.2 μm as the second stage may be connected in series. In addition, various materials may be filtered multiple times. When filtration is performed multiple times, circulation filtration may be performed. Filtration may also be performed under pressure. When filtration is performed under pressure, the pressure to be applied is, for example, preferably 0.01 MPa or more and 1.0 MPa or less, more preferably 0.03 MPa or more and 0.9 MPa or less, even more preferably 0.05 MPa or more and 0.7 MPa or less, and even more preferably 0.05 MPa or more and 0.5 MPa or less.
In addition to filtration using a filter, impurity removal treatment using an adsorbent may be performed. Filter filtration and impurity removal treatment using an adsorbent may be combined. As the adsorbent, a known adsorbent may be used. For example, inorganic adsorbents such as silica gel and zeolite, and organic adsorbents such as activated carbon may be used.
After filtration using a filter, the resin composition filled in the bottle may be subjected to a degassing step by placing it under reduced pressure.

The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing contents, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. "Parts" and "%" are based on mass unless otherwise specified.

<Synthesis of polyimide precursor>
[Synthesis Example P-1: Synthesis of Polyimide Precursor (P-1)]
21.2 g of 4,4'-oxydiphthalic anhydride, 18.0 g of 2-hydroxyethyl methacrylate, 23.9 g of pyridine, and 250 mL of diglyme (diethylene glycol dimethyl ether) were mixed and stirred at a temperature of 60°C for 4 hours to synthesize a diester of 4,4'-oxydiphthalic acid and 2-hydroxyethyl methacrylate. The reaction mixture was then cooled to -10°C, and 17.0 g of thionyl chloride was added over 60 minutes while maintaining the temperature at -10±5°C. After dilution with 50 mL of N-methylpyrrolidone, a solution of 12.6 g of 4,4'-diaminodiphenyl ether dissolved in 100 mL of N-methylpyrrolidone was added dropwise to the reaction mixture at -10±5°C over 60 minutes, and the mixture was stirred at room temperature for 2 hours. Then, 16.1 g of tert-butyl alcohol was added and stirred at room temperature for 1 hour.
Next, 6000 g of water was added to precipitate the polyimide precursor, and the precipitate (water-polyimide precursor mixture) was stirred for 15 minutes. The precipitate (solid polyimide precursor) after stirring was collected by filtration and dissolved in 500 g of tetrahydrofuran. 6000 g of water (poor solvent) was added to the obtained solution to precipitate the polyimide precursor, and the precipitate (water-polyimide precursor mixture) was stirred for 15 minutes. The precipitate (solid polyimide precursor) after stirring was filtered again and dried at 45° C. under reduced pressure for 3 days.
After dissolving 46.6 g of the dried powder in 419.6 g of tetrahydrofuran, 2.3 g of triethylamine was added and stirred at room temperature for 35 minutes. Then, 3000 g of ethanol was added, and the precipitate was collected by filtration. The obtained precipitate was dissolved in 281.8 g of tetrahydrofuran. 17.1 g of water and 46.6 g of ion exchange resin UP6040 (manufactured by AmberTec) were added thereto, and the mixture was stirred for 4 hours. Then, the ion exchange resin was removed by filtration, and the obtained polymer solution was added to 5,600 g of water to obtain a precipitate. The precipitate was collected by filtration and dried at 45 ° C. under reduced pressure for 24 hours, to obtain 45.1 g of polyimide precursor (P-1).
It was confirmed by ¹ H-NMR that the structure of the polyimide precursor (P-1) was a structure represented by the following formula (P-1). The molecular weight of the polyimide precursor (P-1) was measured by gel permeation chromatography (standard polystyrene equivalent) to find that the weight average molecular weight (Mw) was 20,000. In the following formula (P-1), t-Bu represents a tert-butyl group.

[Synthesis Example P-1: Synthesis of Polyimide Precursor (P-2)]
A polyimide precursor (P-2) having a structure represented by the following formula (P-2) was synthesized in the same manner as in Synthesis Example P-1, except that the compounds used were appropriately changed. It was confirmed by ¹ H-NMR that the structure of the polyimide precursor (P-2) was a resin containing two repeating units represented by the following formula (P-2). The molecular weight of the polyimide precursor (P-2) was measured by gel permeation chromatography (standard polystyrene equivalent) and found to have a weight average molecular weight (Mw) of 20,000.

<Examples and Comparative Examples>
In each of the Examples and Comparative Examples, the components shown in the following table were mixed to obtain each resin composition.
Specifically, the content of each component shown in the table is the amount (parts by mass) shown in the "parts by mass" column of each column in the table.
The obtained resin composition was pressure filtered using a polytetrafluoroethylene filter having a pore width of 0.5 μm.
In the table, "-" indicates that the composition does not contain the corresponding component.

Details of each ingredient listed in the table are as follows:

[Polyimide precursor]
P-1 to P-2: Polyimide precursors (P-1) to (P-2) synthesized above

[Monomer (polymerizable compound)]
M-1: Tetraethylene glycol dimethacrylate M-2: Tetraethylene glycol diacrylate M-3: Ethylene glycol dimethacrylate M-4: Diethylene glycol dimethacrylate M-5: Triethylene glycol dimethacrylate M-6: KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.)
M-7: NK Ester A-TMMT (manufactured by Shin-Nakamura Chemical Co., Ltd.)

[Compound A]
U-1 to U-11: Compounds having the following structure

[Polymerization initiator]
I-1: Irgacure OXE-01 (manufactured by BASF)
I-2: Irgacure OXE-02 (manufactured by BASF)
I-3: Irgacure OXE-03 (manufactured by BASF)
I-4: Irgacure OXE-04 (manufactured by BASF)
I-5: Irgacure 784 (manufactured by BASF)
I-6 to I-7: Compounds having the following structure I-8: Omnirad 1316 (manufactured by IGM)

[UV absorber]
V-1 to V-3: Compounds with the following structure V-4: The following synthetic product

<Other Additives: Synthesis of Diazonaphthoquinone Compound V-4>
29.72 g (70 mmol) of 4,4'-(1-(2-(4-hydroxyphenyl)-2-propyl)phenyl)ethylidene)bisphenol (Tris-PA, manufactured by Honshu Chemical Industry Co., Ltd.) was added to the flask. Then, 46.93 g (174.9 mmol) of 1,2-naphthoquinone diazide-5-sulfonic acid chloride and 17.9 g of triethylamine were dissolved in 300 g of acetone with stirring, and the mixture was dropped into the flask using a dropping funnel over 30 minutes, and stirred for 30 minutes at an internal temperature of 30°C. Then, hydrochloric acid was dropped and the mixture was stirred for another 30 minutes. Then, a solution of 1640 g of pure water and 30 g of hydrochloric acid was prepared in a beaker, and the filtrate obtained by filtering the hydrochloride in the reaction solution was dropped into this, and the precipitate was filtered, washed with water, and vacuum dried at 40°C for 50 hours to obtain diazonaphthoquinone compound V-4.

[Adhesive Agent]
C-1: KBM-503 (manufactured by Shin-Etsu Chemical Co., Ltd.)
C-2: N-(3-(triethoxysilyl)propyl)maleamic acid C-3 to C-4: Compounds having the following structures (wherein Et represents an ethyl group)
C-5: Tetraethoxysilane C-6: X-12-1293 (manufactured by Shin-Etsu Chemical Co., Ltd.)
C-7: KR-513 (manufactured by Shin-Etsu Chemical Co., Ltd.)

[Migration Inhibitor]
D-1 to D-5: Compounds having the following structure

[Polymerization inhibitor]
B-1: 4-methoxyphenol B-2: p-benzoquinone B-3 to B-8: Compounds having the following structure

[Thermal Base Generator]
A-1: WPBG-140 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
A-2 to A-3: Compounds having the following structures

〔Additive〕
J-1 to J-4: Compounds having the following structure J-5 (Percumyl D, manufactured by NOF Corporation)

〔solvent〕
NMP: N-methyl-2-pyrrolidone GVL: γ-valerolactone GBL: γ-butyrolactone DMSO: dimethylsulfoxide

<Evaluation of physical properties of polyimide film>
[Film formation process]
In each Example or Comparative Example, a resin composition was dropped onto a Si wafer (hereinafter simply referred to as "substrate") on which a _SiO2 film was formed to a thickness of 100 nm, and a coating film having a thickness shown in the "Film thickness (μm)" column in the table below was formed on the substrate by spin coating and soft baking. The soft bake temperature and soft bake time were the temperatures and times shown in the "Soft bake temperature (°C)" and "Soft bake time (min)" columns in the table, respectively.
Then, the film was subjected to pattern exposure at 400 mj/cm ² using an i-line exposure machine.
After exposure, the substrate was developed with the developer shown in the "Development" column in the table, and then rinsed with the rinse solution shown in the "Rinse" column in the table below to obtain a patterned film of the polyimide precursor on the substrate.
The substrate provided with the above-mentioned patterned film was subjected to a vacuum gas replacement oven (450PB8-2P-CP, manufactured by YES Corporation) by reducing the pressure to the degree of vacuum indicated in the "Cure method (degree of vacuum)" column in the table below before and during the curing heating, and was heated and cured at the temperature indicated in the "Cure temperature (°C)" column in the table for the time indicated in the "Cure time (h)" column in the table, to obtain a polyimide film.
In this specification, 1 Torr = 133.32 Pa.
The patterned polyimide film was peeled off from the substrate by a hydrofluoric acid treatment to obtain a polyimide piece.
Moreover, the resin composition used in Examples 55 to 56 in the table below is the same as the resin composition used in Example 1, the resin composition used in Examples 57 to 61 is the same as the resin composition used in Example 1, and the resin composition used in Example 62 is the same as the resin composition used in Comparative Example 1. Moreover, the description of "rinsing solution A" in the table means that a solution containing 5% by mass of the above-mentioned U-2 compound relative to PGMEA was used as the rinsing solution.
For the examples marked "Yes" in the "Decompression" column in the table, the pressure was reduced to the vacuum level noted in the "Cure method (vacuum level)" column before and during the cure heating. In Comparative Example 2, " _N2 " in the "Cure method (vacuum level)" column in the table means that heating was performed under a nitrogen atmosphere at 1 atmosphere (=101,325 Pa).
In Examples 54 and 55, after rinsing and before the start of pressure reduction, the following treatment solution was brought into contact with the rinsed pattern, and heating was carried out at 100° C. for 1 hour.
Treatment solution: A mixture of 90.3 parts by mass of PGMEA, 4.7 parts by mass of GBL, 5 parts by mass of N-(3-dimethylaminopropyl)methacrylamide, and 0.002 parts by mass of 4-methoxyphenol. The polyimide piece obtained above was put into a thermomechanical analyzer (TMA) to evaluate the thermal expansion coefficient. The thermal expansion coefficient was 53.0 ppm/K, and it was confirmed that the polyimide film had little thermal expansion and was excellent.
The polyimide pieces obtained above were subjected to a tensile test, and the average tensile elongation of N=6 measurements was 44.8%.

[Evaluation of heat resistance and moisture resistance reliability]
In each example or comparative example, each resin composition was formed into a film and cured on a 4-inch TEG (Test Element Group) substrate having a copper wiring with a width of 10 μm, and the obtained substrate was subjected to reliability tests of 2000 hours at 150° C. (heat resistance reliability) and 500 hours at 121° C. and a relative humidity of 100% (humidity resistance reliability). The film formation and curing were performed in the same manner as the method described in the above-mentioned "film formation process", except that the exposure was performed on the entire surface.
After each reliability test, the cross section of the Cu wiring portion was observed with a SEM (Scanning Electron Microscope).
The reliability was evaluated according to the following evaluation criteria: The evaluation results of heat resistance reliability are shown in the "heat resistance reliability" column in the table, and the evaluation results of moisture resistance reliability are shown in the "moisture resistance reliability" column in the table.
-Evaluation criteria-
A: No abnormalities such as voids or peeling were observed in the copper wiring portion.
B: A small number of voids (maximum diameter less than 0.5 μm) were observed in the copper wiring.
C: Significant voids (voids larger than B) or cracks were observed in the copper wiring.

[Evaluation of chemical resistance]
In each Example or Comparative Example, each resin composition was formed into a film on a 4-inch Si wafer and cured, and then the obtained wafer was immersed in N-methyl-2-pyrrolidone for 3 hours, washed with isopropyl alcohol, and then air-dried. The presence or absence of cracks in the cured film (polyimide film) on the obtained wafer was visually observed. The above film formation and curing were performed in the same manner as that described in the "Film formation process" above, except that the exposure was performed on the entire surface.
The chemical resistance was evaluated according to the following evaluation criteria. The evaluation results are shown in the "Chemical resistance" column in the table.
-Evaluation criteria-
A: No cracks were observed over the entire surface of the wafer. B: Cracks were observed in parts of the wafer. C: Cracks were observed over the entire surface of the wafer.

[Bias HAST (Highly Accelerated Stress Test)]
A bias HAST test was carried out for each of the examples and comparative examples.
Biased HAST testing was performed using a simple test vehicle 100 as shown in FIG.
FIG. 1 is a schematic cross-sectional view of a test vehicle used in the biased HAST test.
The test vehicle 100 was constructed by laminating, in this order, a _SiO2 layer 104, a patterned Ti layer 106, and a patterned 10 μm L/S (line and space) comb-shaped copper wiring 108 on a Si wafer (silicon wafer) 102, and the wiring was covered with a cured product 110 of each composition. In FIG. 1, d1 and d2 are 10 μm.
Specifically, a coating film of each resin composition was formed on a _SiO2 wafer and Cu wiring included in the test vehicle. Then, a cured product 110 was formed by the same method as that described in the above-mentioned "film formation process".
Biased HAST tests were performed with each test vehicle.
The bias HAST test was carried out using a Hirayama oven at 130°C/85% RH (relative humidity)/96h (96 hours). A voltage of 15V was applied during the HAST test, and the test was judged based on the presence or absence of a short circuit in the wiring during the test. A short circuit was judged to have occurred when the electrical resistance value was less than 10 ⁵ Ω. The evaluation results are shown in the "bHAST" column in the table.
-Evaluation criteria-
A: No wiring short was found at 96h.
B: A wiring short was found between 31 hours and 96 hours.
C: A wiring short was observed within 31 hours.

From the above results, it is apparent that the cured product formed by the method for producing a cured product of the present invention has excellent heat resistance reliability and chemical resistance.
The method for producing a cured product according to Comparative Example 1 does not satisfy either condition 1 or condition 2. In addition, the method for producing a cured product according to Comparative Example 2 does not include a decompression step. It is clear that the cured product obtained by the methods for producing a cured product according to these Comparative Examples is inferior in heat resistance reliability and chemical resistance.

100 Test vehicle 102 Si wafer 104 _SiO2 layer 106 Ti layer 108 Cu wiring 110 Hardened product

Claims

a decompression step of exposing the resin layer to a pressure lower than 101,325 Pa; and
a heating step of heating the resin layer under the pressure,
the resin layer is a layer formed from a resin composition containing a polyimide precursor and a solvent,
A method for producing a cured product, which satisfies at least one of the following conditions 1 and 2:
Condition 1: The resin composition further contains a compound A having at least one bond selected from a urethane bond and a urea bond, and at least one functional group selected from a tert-butyl group, a hydroxyl group, and a group containing an ethylenically unsaturated bond.
Condition 2: The method includes a step of contacting the resin layer with a treatment liquid containing the compound A prior to the depressurization step.
The method for producing a cured product according to claim 1, further comprising, prior to the decompression step, a step of exposing a photosensitive resin layer formed from the resin composition further containing a photopolymerization initiator, and a step of developing the exposed photosensitive resin layer to obtain the resin layer.
The method for producing a cured product according to claim 2, wherein the photopolymerization initiator comprises a compound having a structure represented by the following formula (PPI-1):

In formula (PPI-1), R 1 is an organic group having 1 to 9 carbon atoms, R 2 is a methyl group or a phenyl group, R 3 is each independently an organic group having 1 to 9 carbon atoms, and n is an integer of 0 to 5.
The method for producing a cured product according to any one of claims 1 to 3, wherein the decompression step is a step of exposing the resin layer to a pressure of 0.07 MPa or less.
The method for producing a cured product according to any one of claims 1 to 3, wherein the heating temperature in the heating step is 140°C or higher.
The method for producing a cured product according to any one of claims 1 to 3, wherein the compound A includes at least one compound selected from the group consisting of a compound having a tert-butyl group and a urethane bond, and a compound having a urea bond, two or more hydroxy groups, and a group containing an ethylenically unsaturated bond.
The method for producing a cured product according to any one of claims 1 to 3, wherein the resin layer further contains an azole compound.
The method for producing a cured product according to any one of claims 1 to 3, wherein the resin layer contains an organometallic complex containing at least one metal atom selected from titanium, zirconium, and hafnium.
The method for producing a cured product according to any one of claims 1 to 3, in which the linear thermal expansion coefficient of the resulting cured product in the range of 25°C to 125°C is 55 ppm/K or less.
The method for producing a cured product according to any one of claims 1 to 3, in which the tensile modulus of the resulting cured product at 25°C is 3.0 GPa or more.
The method for producing a cured product according to any one of claims 1 to 3, in which the tensile elongation of the resulting cured product at 25°C is 40% or more.
A method for producing a laminate, comprising the method for producing a cured product according to any one of claims 1 to 3.
A method for manufacturing a semiconductor device, comprising the method for manufacturing a cured product according to any one of claims 1 to 3.
A semiconductor device comprising a cured product obtained by the method for producing a cured product according to any one of claims 1 to 3.