JP6816551B2 - Thermosetting resin composition for coreless substrates, prepregs for coreless substrates, coreless substrates, coreless substrate manufacturing methods and semiconductor packages - Google Patents

Description

The present invention relates to a thermosetting resin composition for a coreless substrate, a prepreg for a coreless substrate, a coreless substrate, a method for manufacturing a coreless substrate, and a semiconductor package.

Due to the recent miniaturization and higher performance of electronic devices, printed wiring boards are required to have higher wiring densities and higher integrations as well as thinner substrates than before.
As a package structure based on these requirements, for example, Patent Document 1 and Patent Document 2 propose a coreless substrate mainly composed of a build-up layer capable of high-density wiring without having a core substrate. .. This coreless substrate is obtained by forming a build-up layer on a support (core substrate) such as a metal plate and then removing the support (core substrate), that is, in this case, the build-up layer. Only. As the build-up material used for forming the coreless substrate, for example, a prepreg obtained by impregnating a glass cloth with a resin composition is used.

Since the rigidity of the coreless substrate is reduced due to the thinning by removing the support (core substrate), the problem that the semiconductor package warps when the semiconductor element is mounted and packaged becomes more remarkable. Warpage is considered to be one of the factors that cause poor connection between a semiconductor element and a printed wiring board, and in a coreless substrate, even more effective reduction of warpage is desired.

One of the factors that cause the semiconductor package to warp is the difference in the coefficient of thermal expansion between the semiconductor element and the printed wiring board. In general, since the coefficient of thermal expansion of a printed wiring board is larger than the coefficient of thermal expansion of a semiconductor element, stress is generated due to the thermal history applied when the semiconductor element is mounted, and warpage occurs. Therefore, in order to suppress the warpage of the semiconductor package, it is necessary to reduce the coefficient of thermal expansion of the printed wiring board to reduce the difference from the coefficient of thermal expansion of the semiconductor element, and in a coreless substrate in which the problem of warpage is remarkable. Is required to have low thermal expansion at a higher level.

Here, it is generally known that the coefficient of thermal expansion of the prepreg obtained by impregnating the glass cloth with the resin composition follows the Scapery formula represented by the following formula.
A ≒ (ArErFr + AgEgFg) / (ErFr + EgFg)
(In the above formula, A is the coefficient of thermal expansion of the prepreg, Ar is the coefficient of thermal expansion of the resin composition, Er is the coefficient of elasticity of the resin composition, Fr is the volume fraction of the resin composition, and Ag is the coefficient of thermal expansion of the glass cloth. , Eg represents the coefficient of elasticity of the glass cloth, and Fg represents the volume fraction of the glass cloth.)
From the above Scapery equation, it is considered that when glass cloth having the same physical characteristics at an arbitrary volume fraction is used, the prepreg can be reduced in thermal expansion by reducing the elastic modulus and the coefficient of thermal expansion of the resin composition.

For example, Patent Document 3 discloses a prepreg formed of a resin composition containing a specific low elasticity component and a woven fabric base material as a prepreg capable of reducing warpage of a semiconductor package.

Japanese Unexamined Patent Publication No. 2005-72085 JP-A-2002-26171 JP 2015-189834

However, the prepreg disclosed in Patent Document 3 does not satisfy the level of low warpage required for the coreless substrate as described above, and further improvement is required.

Further, the prepreg used for the coreless substrate needs to be adjusted to have a higher resin content than the prepreg used for the conventional core formation in order to improve the embedding property of the wiring. When the resin content of the prepreg is increased, the dimensional change rate due to heat history or the like tends to increase. Therefore, the prepreg for a coreless substrate is required to have a higher degree of dimensional stability than the conventional prepreg. Examples of the method for improving the dimensional stability include a method of highly filling the resin composition with an inorganic filler. In this case, both good wiring embedding property and low elasticity of the resin composition can be achieved. It can be difficult.

In view of these circumstances, an object of the present invention is to provide a thermosetting resin composition for a coreless substrate, which has a high level of low warpage and dimensional stability required for a coreless substrate, and a coreless substrate using the same. It is to provide a prepreg for use, a coreless substrate, a method for manufacturing a coreless substrate, and a semiconductor package.

As a result of diligent research to achieve the above object, the present inventors have found that a thermosetting resin composition containing a specific siloxane compound and a maleimide compound has a low warpage property of a level required for a coreless substrate. We have found that the present invention is highly compatible with dimensional stability.
That is, the present invention provides the following [1] to [11].
[1] Containing a siloxane compound (a) having at least two primary amino groups in one molecule and a maleimide compound (b) having at least two N-substituted maleimide groups in one molecule. , Thermosetting resin composition for coreless substrates.
[2] A reaction product of a siloxane compound (a) having at least two primary amino groups in one molecule and a maleimide compound (b) having at least two N-substituted maleimide groups in one molecule. A thermosetting resin composition for a coreless substrate, which contains a siloxane-modified polyimide (X).
[3] The above-mentioned [1] or [2], wherein the siloxane compound (a) having at least two primary amino groups in the one molecule is represented by the following general formula (1). Thermosetting resin composition for coreless substrates.

(In the general formula (1), R ^a1 , R ^a2 , R ^a3 and R ^a4 each independently represent an alkyl group, a phenyl group or a substituted phenyl group. X ^a1 and X ^a2 are each independently divalent organic. Represents a group, m is an integer from 1 to 50.)

[4] The thermosetting resin composition for a coreless substrate according to any one of the above [1] to [3], which further contains a thermoplastic elastomer (c).
[5] The thermosetting resin composition for a coreless substrate according to any one of the above [1] to [4], which further contains a thermosetting resin (d).
[6] The thermosetting resin composition for a coreless substrate according to any one of the above [1] to [5], which further contains a curing accelerator (e).
[7] The thermosetting resin composition for a coreless substrate according to any one of the above [1] to [6], which further contains an inorganic filler (f).
[8] A prepreg for a coreless substrate, which comprises the thermosetting resin composition according to any one of the above [1] to [7].
[9] A coreless substrate containing an insulating layer formed by using the prepreg for a coreless substrate according to the above [8].
[10] A semiconductor package in which a semiconductor element is mounted on the coreless substrate according to the above [9].
[11] A method for manufacturing a coreless substrate, wherein a build-up layer formed by alternately laminating conductor layers and insulating layers is formed on a support, and then the build-up layer is separated from the support. A method for manufacturing a coreless substrate, wherein at least one layer of the insulating layer is formed by using the prepreg for a coreless substrate according to the above [8].

According to the present invention, a thermosetting resin composition for a coreless substrate, which has a high degree of both low warpage and dimensional stability required for a coreless substrate, and a prepreg for a coreless substrate and a coreless substrate using the same. , A method for manufacturing a coreless substrate and a semiconductor package can be provided.

It is a schematic diagram which shows one aspect of the manufacturing method of the coreless substrate of this invention. It is a schematic diagram which shows the evaluation substrate of the dimensional change rate in an Example.

[Thermosetting resin composition for coreless substrates]
The thermosetting resin composition for a coreless substrate of the present invention (hereinafter, also simply referred to as “thermosetting resin composition”) is a siloxane compound (a) having at least two primary amino groups in one molecule. Hereinafter, it is also simply referred to as “amino-modified siloxane compound (a)” or “component (a)”) and a maleimide compound (b) having at least two N-substituted maleimide groups in one molecule (hereinafter, “maleimide compound”). (B) ”or“ (b) component ”), which is a thermosetting resin composition for a coreless substrate.

<Amino-modified siloxane compound (a)>
The amino-modified siloxane compound (a) is not particularly limited as long as it is a siloxane compound having at least two primary amino groups in one molecule.
The amino-modified siloxane compound (a) is preferably a siloxane compound having two primary amino groups in one molecule.
The amino-modified siloxane compound (a) may have a primary amino group at either or both of the side chains or the ends of the siloxane skeleton, and has the primary amino group at the ends from the viewpoint of availability and low warpage. It is preferable, and it is more preferable to have it at both ends (hereinafter, a siloxane compound having a primary amino group at both ends is also referred to as "both-terminal amino-modified siloxane compound"). From the same viewpoint, the amino-modified siloxane compound (a) is preferably represented by the following general formula (1).

(In the general formula (1), R ^a1 , R ^a2 , R ^a3 and R ^a4 each independently represent an alkyl group, a phenyl group or a substituted phenyl group. X ^a1 and X ^a2 are each independently divalent organic. Represents a group, m is an integer from 1 to 50.)

In the general formula (1), examples of the alkyl group represented by Ra ¹ , Ra ² , Ra ³ and Ra ⁴ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and t. -Butyl group, n-pentyl group and the like can be mentioned. The alkyl group is preferably an alkyl group having 1 to 5 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and further preferably a methyl group.
Examples of the substituent contained in the phenyl group in the substituted phenyl group include an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, and an alkynyl group having 2 to 5 carbon atoms. Examples of the alkyl group having 1 to 5 carbon atoms include the same alkyl groups as those described above. Examples of the alkenyl group having 2 to 5 carbon atoms include a vinyl group and an allyl group. Examples of the alkynyl group having 2 to 5 carbon atoms include an ethynyl group and a propargyl group.
Among the above, as R ^a1 , R ^a2 , R ^a3 and R ^a4 , a methyl group or a phenyl group is preferable.
Examples of the divalent organic group represented by X ^a1 and X ^a2 include an alkylene group, an alkenylene group, an alkynylene group, an arylene group, —O— or a divalent linking group in which these are combined. Examples of the alkylene group include an alkylene group having 1 to 10 carbon atoms such as a methylene group, an ethylene group and a propylene group. Examples of the alkenylene group include an alkenylene group having 2 to 10 carbon atoms. Examples of the alkynylene group include an alkynylene group having 2 to 10 carbon atoms. Examples of the arylene group include an arylene group having 6 to 20 carbon atoms such as a phenylene group and a naphthylene group.
m is an integer of 1 to 50, preferably an integer of 4 to 46, and more preferably an integer of 10 to 42. When m is an integer of 2 or more, the plurality of ^Ra1s or ^Ra2s may be the same or different from each other.

As the component (a), a commercially available product can be used. For example, as the component (a) having a methyl group in the side chain, "KF-8010" (functional group equivalent of amino group 430 g / mol), "X-" 22-161A ”(functional group equivalent of amino group 800 g / mol),“ X-22-161B ”(functional group equivalent of amino group 1,500 g / mol),“ KF-8012 ”(functional group equivalent of amino group 2) , 200 g / mol), "KF-8008" (functional group equivalent of amino group 5,700 g / mol), "X-22-9409" (functional group equivalent of amino group 700 g / mol) (above, Shinetsu Chemical Industry Co., Ltd.) (Made by company), etc. In addition, as the component (a) having a phenyl group in the side chain, "X-22-1660B-3" (functional group equivalent of amino group 2,200 g / mol) (manufactured by Shin-Etsu Chemical Industry Co., Ltd.), "BY-". "16-853U" (functional group equivalent of amino group 460 g / mol), "BY-16-853" (functional group equivalent of amino group 650 g / mol), "BY-16-853B" (functional group equivalent of amino group 2) , 200 g / mol) (all manufactured by Toray Dow Corning Co., Ltd.) and the like. These may be used alone or in combination of two or more.
Among these, from the viewpoint of low water absorption, "X-22-161A", "X-22-161B", "KF-8012", "KF-8008", "X-22-1660B-3", ""BY-16-853B" is preferable, and "X-22-161A", "X-22-161B", "KF-8012", and "X-22-1660B-3" are more preferable from the viewpoint of low thermal expansion. ..

The functional group equivalent of the amino group contained in the component (a) is preferably 300 to 3,000 g / mol, more preferably 400 to 2,500 g / mol, and even more preferably 600 to 2,300 g / mol.

The content of the amino-modified siloxane compound (a) in the thermosetting resin composition is thermosetting from the viewpoints of low warpage, dimensional stability, low thermal expansion, low elasticity, heat resistance, and adhesion to metal circuits. With respect to 100 parts by mass of the solid content of the resin component in the sex resin composition, 8 to 50 parts by mass is preferable, 9 to 45 parts by mass is more preferable, and 10 to 40 parts by mass is further preferable.
Here, the solid content in the present embodiment means a component in the thermosetting resin composition other than a volatile substance such as water and a solvent described later. That is, the solid content includes liquid, starch syrup, or wax at room temperature around 25 ° C., and does not necessarily mean that it is solid.

<Maleimide compound (b) having at least two N-substituted maleimide groups in one molecule>
The maleimide compound (b) is not particularly limited as long as it is a maleimide compound having at least two N-substituted maleimide groups in one molecule.
As the maleimide compound (b), a maleimide compound having two N-substituted maleimide groups in one molecule is preferable, and a compound represented by the following general formula (b-1) is more preferable.

(In the general formula (b-1), X ^b1 is a group represented by the following general formulas (b1-1), (b1-2), (b1-3) or (b1-4)).

(In the general formula (b1-1), R ^b1 is an aliphatic hydrocarbon group or a halogen atom having 1 to 5 carbon atoms independently. P is an integer of 0 to 4.)

(In the general formula (b1-2), R ^b2 and R ^b3 are independently aliphatic hydrocarbon groups or halogen atoms having 1 to 5 carbon atoms. X ^b2 is an alkylene group having 1 to 5 carbon atoms and carbon. The number 2 to 5 of an alkylidene group, an ether group, a sulfide group, a sulfonyl group, a carbooxy group, a keto group, a single bond or a group represented by the following general formula (b1-2-1). Q and r are independent of each other. Is an integer from 0 to 4.)

(In the general formula (b1-2-1), R ^b4 and R ^b5 are independently aliphatic hydrocarbon groups having 1 to 5 carbon atoms or halogen atoms. X ^b3 is an alkylene group having 1 to 5 carbon atoms. , Alkylidene group, ether group, sulfide group, sulfonyl group, carbooxy group, keto group or single bond having 2 to 5 carbon atoms. S and t are independently integers of 0 to 4).

(In the general formula (b1-3), n is an integer of 1 to 10.)

(In the general formula (b1-4), R ^b6 and R ^b7 are independently hydrogen atoms or aliphatic hydrocarbon groups having 1 to 5 carbon atoms. U is an integer of 1 to 8.)

In the general formula (b1-1), examples of the aliphatic hydrocarbon group represented by R ^b1 include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group and a t-butyl group. , N-pentyl group and the like. The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 3 carbon atoms, and more preferably a methyl group. Further, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like.
Among the above, an aliphatic hydrocarbon group having 1 to 5 carbon atoms is preferable as R ^b1 .
p is an integer of 0 to 4, and from the viewpoint of availability, it is preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0. When p is an integer of 2 or more, the plurality of R ^b1s may be the same or different.

In the general formula (b1-2), examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by R ^b2 and R ^b3 and the halogen atom are the same as those in the case of R ^b1 . The aliphatic hydrocarbon group is preferably an aliphatic hydrocarbon group having 1 to 3 carbon atoms, more preferably a methyl group and an ethyl group, and further preferably an ethyl group.
Examples of the alkylene group having 1 to 5 carbon atoms represented by X ^b2 include a methylene group, a 1,2-dimethylene group, a 1,3-trimethylene group, a 1,4-tetramethylene group, a 1,5-pentamethylene group and the like. Can be mentioned. The alkylene group is preferably an alkylene group having 1 to 3 carbon atoms, and more preferably a methylene group, from the viewpoint of heat resistance and low thermal expansion.
Examples of the alkylidene group having 2 to 5 carbon atoms represented by X ^b2 include an ethylidene group, a propylidene group, an isopropylidene group, a butylidene group, an isobutylidene group, a pentylidene group and an isopentylidene group. Among these, an isopropylidene group is preferable from the viewpoint of heat resistance and low thermal expansion.
Among the above options, X ^b2 is preferably an alkylene group having 1 to 5 carbon atoms and an alkylidene group having 2 to 5 carbon atoms. More preferred are as described above.
q and r are each independently an integer of 0 to 4, and from the viewpoint of availability, both are preferably an integer of 0 to 2, more preferably 0 or 2. When q or r is an integer of 2 or more, the plurality of R ^b2s or R ^b3s may be the same or different from each other.

In the general formula (b1-2-1), examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by R ^b4 and R ^b5 and the halogen atom are the same as those in the cases of R ^b2 and R ^b3. , The preferred ones are the same.
The alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by X ^b3 are the same as the alkylene group having 1 to 5 carbon atoms and the alkylidene group having 2 to 5 carbon atoms represented by X ^b2. The same is true for the preferred ones.
Among the above options, X ^b3 is preferably an alkylidene group having 2 to 5 carbon atoms, and more preferable one is as described above.
s and t are integers of 0 to 4, and from the viewpoint of availability, both are preferably integers of 0 to 2, more preferably 0 or 1, and even more preferably 0. When s or t is an integer of 2 or more, the plurality of R ^b4s or R ^b5s may be the same or different from each other.
The general formula (b1-2-1) is preferably represented by the following general formula (b1-2-1').

(X ^b3 , R ^b4 , R ^b5 , s and t in the general formula (b1-2-1') are the same as those in the general formula (b1-2-1), and the preferable ones are also the same. .)

The group represented by the general formula (b1-2) is preferably a group represented by the following general formula (b1-2'), and any one of the following (b1-i) to (b1-iii). It is more preferable that the group is represented by (b1-i) or (b1-iii) below.

(X ^b2 , R ^b2 , R ^b3 , q and r in the general formula (b1-2') are the same as those in the general formula (b1-2'), and the preferable ones are also the same.)

In the general formula (b1-3), n is an integer of 1 to 10, preferably an integer of 1 to 5, and more preferably an integer of 1 to 3 from the viewpoint of availability.
In the general formula (b1-4), examples of the aliphatic hydrocarbon group having 1 to 5 carbon atoms represented by R ^b6 and R ^b7 are the same as those in the case of R ^{b1 in} the general formula (b1-1). And so is the preferred one. u is an integer of 1 to 8, preferably an integer of 1 to 3, and more preferably 1.

In the general formula (b-1), X ^b1 is any of the groups represented by the general formula (b1-1), (b1-2), (b1-3) or (b1-4). Of these, the group represented by the general formula (b1-2) is preferable from the viewpoint of low warpage, dimensional stability, heat resistance and availability.

Specific examples of the maleimide compound (b) include bis (4-maleimidephenyl) methane, polyphenylmethane maleimide, bis (4-maleimidephenyl) ether, bis (4-maleimidephenyl) sulfone, 3,3'-dimethyl-. 5,5'-diethyl-4,4'-diphenylmethanebismaleimide, 4-methyl-1,3-phenylenebismaleimide, m-phenylenebismaleimide, 2,2-bis [4- (4-maleimidephenoxy) phenyl] Examples include propane. These may be used alone or in combination of two or more.
Among these, bis (4-maleimidephenyl) methane, bis (4-maleimidephenyl) sulfone, 3,3'-dimethyl-5,5'-diethyl from the viewpoint of high reactivity and higher heat resistance. -4,4'-diphenylmethanebismaleimide, 2,2-bis [4- (4-maleimidephenoxy) phenyl] propane is preferable, and 3,3'-dimethyl-5,5'from the viewpoint of solubility in a solvent. -Didiphenyl-4,4'-diphenylmethane bismaleimide, bis (4-maleimidephenyl) methane, 2,2-bis [4- (4-maleimidephenoxy) phenyl] propane are more preferred, and bis 4-Maleimidephenyl) methane and 2,2-bis [4- (4-maleimidephenoxy) phenyl] propane are more preferred.

The content of the maleimide compound (b) in the thermosetting resin composition is a thermosetting resin from the viewpoints of low warpage, dimensional stability, low thermal expansion, low elasticity, heat resistance and adhesion to a metal circuit. With respect to 100 parts by mass of the solid content of the resin component in the composition, 30 to 90 parts by mass is preferable, 35 to 85 parts by mass is more preferable, and 45 to 80 parts by mass is further preferable.

The component (a) and the component (b) in the thermosetting resin composition of the present invention may be a mixture of the components (a) and (b) as they are, or the components (a) and (b) may be reacted with each other. , Siloxane-modified polyimide [hereinafter referred to as siloxane-modified polyimide (X). ] May be used. That is, the thermosetting resin composition of the present invention may be a thermosetting resin composition for a coreless substrate containing a component (a) and a component (b), and the components (a) and (b) may be used. It may be a thermosetting resin composition for a coreless substrate containing a siloxane-modified polyimide (X) which is a reaction product with. The siloxane-modified polyimide (X) will be described below.

<siloxane-modified polyimide (X)>
The siloxane-modified polyimide (X) is obtained by reacting the component (a) with the component (b), and has a structural unit (a') derived from the component (a) and a structural unit derived from the component (b). (B') and.
There is no particular limitation on the reaction method between the component (a) and the component (b). The reaction temperature is preferably 70 to 200 ° C., more preferably 80 to 150 ° C., and even more preferably 100 to 130 ° C. from the viewpoint of productivity and sufficient progress of the reaction. The reaction time is not particularly limited, but is preferably 0.5 to 10 hours, more preferably 1 to 6 hours.

The reaction between the component (a) and the component (b) is preferably carried out in an organic solvent. Examples of the organic solvent include alcohol solvents such as ethanol, propanol, butanol, methyl cellosolve, butyl cellosolve and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; acetate ethyl ester and γ-butyrolactone. Ester-based solvents such as; ether-based solvents such as tetrahydrofuran; aromatic solvents such as toluene, xylene, mesityrene; nitrogen atom-containing solvents such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone; sulfur atom-containing solvents such as dimethylsulfoxide And so on. These may be used alone or in combination of two or more.
Among these, cyclohexanone, propylene glycol monomethyl ether, methyl cellosolve, and γ-butyrolactone are preferable from the viewpoint of solubility, and cyclohexanone and propylene glycol are preferable from the viewpoint of low toxicity and high volatility and difficult to remain as a residual solvent. Monomethyl ether and dimethylacetamide are preferable, and propylene glycol monomethyl ether is more preferable.
The amount of the organic solvent used is not particularly limited, but from the viewpoint of solubility and reaction rate, 25 to 1,000 parts by mass is preferable with respect to 100 parts by mass in total of the components (a) and (b), and 40. ~ 500 parts by mass is more preferable, and 50 to 200 parts by mass is further preferable.

After completion of the above reaction, the obtained reaction mixture can be mixed with other components as it is without purifying the reaction product to prepare a thermosetting resin composition containing the siloxane-modified polyimide (X). it can.

In the reaction, the ratio of the component (a) and the component (b) used is such that the equivalent of the maleimide group of the component (b) is the primary amino group of the component (a) from the viewpoint of preventing gelation and heat resistance. It is preferable to exceed the equivalent amount of. That is, the ratio [(b) / (a)] of the equivalent of the maleimide group of the component (b) to the equivalent of the primary amino group of the component (a) is preferably more than 1, preferably 2-35. More preferably, 10 to 35 is even more preferable.

When the thermosetting resin composition contains the siloxane-modified polyimide (X), the content thereof is preferably 40 parts by mass or more with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. 50 parts by mass or more is more preferable, and 60 parts by mass or more is further preferable. The upper limit of the content of the siloxane-modified polyimide (X) is not particularly limited, and may be 100 parts by mass or less with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. It may be 5 parts by mass or less, or 85 parts by mass or less.

The content of the structural unit (a') in the siloxane-modified polyimide (X) is 8 to 50 from the viewpoints of low warpage, dimensional stability, low thermal expansion, low elasticity, heat resistance, and adhesion to metal circuits. It is preferably by mass, more preferably 10 to 45% by mass, still more preferably 12 to 40% by mass.
The content of the structural unit (b') in the siloxane-modified polyimide (X) is 50 to 92 from the viewpoints of low warpage, dimensional stability, low thermal expansion, low elasticity, heat resistance and adhesion to metal circuits. It is preferably by mass, more preferably 55 to 90% by mass, still more preferably 60 to 80% by mass.
The preferable contents of the structural unit (a') and the structural unit (b') in the thermosetting resin composition are based on 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. , Each of which is the same as the preferred embodiment of the contents of the component (a) and the component (b) in the thermosetting resin composition.
However, when the thermosetting resin composition further contains one or more selected from the group consisting of the component (a) and the component (b) in addition to the siloxane-modified polyimide (X), each component and each component are derived. It is preferable that the total content of the above with the structural unit is a preferred embodiment of the contents of the component (a) and the component (b) in the thermosetting resin composition.

<Thermoplastic elastomer (c)>
The thermosetting resin composition of the present invention may further contain a thermoplastic elastomer (c).
Examples of the thermoplastic elastomer (c) include styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, urethane-based thermoplastic elastomers, polyester-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, acrylic-based thermoplastic elastomers, and silicone-based thermoplastics. Examples include plastic elastomers and derivatives thereof. These consist of a hard segment component and a soft segment component, and the former generally contributes to heat resistance and strength, and the latter contributes to flexibility and toughness. These may be used alone or in combination of two or more.
Among these, styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, polyamide-based thermoplastic elastomers, and silicone-based thermoplastic elastomers are preferable, and styrene-based thermoplastic elastomers are more preferable, from the viewpoint of heat resistance and insulation reliability.
The styrene-based thermoplastic elastomer is preferably a thermoplastic elastomer having a structural unit derived from styrene represented by the following general formula (c-1).

Examples of the structural unit other than the styrene-derived structural unit contained in the styrene-based thermoplastic elastomer include a butadiene-derived structural unit, an isoprene-derived structural unit, a maleic acid-derived structural unit, and a maleic anhydride-derived structural unit. These may be contained alone or in combination of two or more.
The structural unit derived from butadiene and the structural unit derived from isoprene are preferably hydrogenated. When hydrogenated, the structural unit derived from butadiene is a structural unit in which ethylene units and butylene units are mixed, and the structural unit derived from isoprene is a structural unit in which ethylene units and propylene units are mixed.

Styrene-based thermoplastic elastomers include hydrogenated additives of styrene-butadiene-styrene block copolymers and styrene-isoprene-styrene from the viewpoints of low thermal expansion, adhesion strength to metal circuits, heat resistance, elasticity and high frequency characteristics. It is preferable that the amount is one or more selected from the group consisting of the hydrogenated compounds of block copolymers, and the hydrogenated substances of styrene-butadiene-styrene block copolymers are more preferable.
The hydrogenated additives of the styrene-butadiene-styrene block copolymer include SEBS in which the hydrogenation rate of the carbon-carbon double bond is usually 90% or more (preferably 95% or more), and 1 in the butadiene block. , 2-bonding site carbon-carbon double bond is partially hydrogenated SBBS (hydrogenation rate to the total carbon-carbon double bond is about 60-85%). Among these, SEBS is more preferable.

The thermoplastic elastomer (c) may have a reactive functional group at least one of the molecular terminal and the molecular chain. Examples of the reactive functional group include an epoxy group, a hydroxyl group, a carboxy group, an amino group, an amide group, an isocyanato group, an acrylic group, a (meth) acrylic group, a vinyl group and the like. By having a reactive functional group, the compatibility with other resin components is improved, and the internal stress generated at the time of curing of the thermosetting resin composition can be more effectively reduced, and as a result, the coreless substrate can be obtained. It is possible to remarkably reduce the warp of the. In particular, from the viewpoint of low thermal expansion and adhesive strength with a metal circuit, it is preferable to have at least one selected from the group consisting of an epoxy group, a hydroxyl group, a carboxy group, an amino group and an amide group, and has heat resistance and insulation reliability. From the viewpoint of sex, it is more preferable to have one or more selected from the group consisting of an epoxy group and a carboxy group.

When the thermosetting resin composition contains the thermoplastic elastomer (c), the content of the thermoplastic elastomer (c) improves the compatibility with other resin components, and effectively reduces the curing shrinkage and the low thermal expansion of the cured product. From the viewpoint of expression, 0.1 to 50 parts by mass is preferable, 2 to 30 parts by mass is more preferable, and 4 to 25 parts by mass is preferable with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. More preferred.

<Thermosetting resin (d)>
The thermosetting resin composition may further contain the thermosetting resin (d). However, the thermosetting resin (d) does not contain the component (a) and the component (b).
Examples of the thermosetting resin (d) include epoxy resin, phenol resin, unsaturated imide resin (however, the component (b) is not included), cyanate resin, isocyanate resin, benzoxazine resin, oxetane resin, and amino resin. (However, the component (a) is not included), unsaturated polyester resin, allyl resin, dicyclopentadiene resin, silicone resin, triazine resin, melamine resin and the like can be mentioned. These may be used alone or in combination of two or more. Among these, one or more selected from the group consisting of epoxy resin and cyanate resin is preferable, and epoxy resin is more preferable, from the viewpoint of moldability and electrical insulation, and from the viewpoint of adhesive strength with a metal circuit.

Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, α-naphthol / cresol novolac type epoxy resin, and bisphenol A novolac. Type epoxy resin, bisphenol F novolac type epoxy resin, stillben type epoxy resin, triazine skeleton-containing epoxy resin, fluorene skeleton-containing epoxy resin, triphenol methane type epoxy resin, biphenyl type epoxy resin, xylylene type epoxy resin, biphenyl aralkyl type epoxy resin , Naphthalene type epoxy resin, dicyclopentadiene type epoxy resin, alicyclic epoxy resin, polycyclic aromatic diglycidyl ether compounds such as polyfunctional phenols and anthracene, phosphorus-containing epoxy resin in which a phosphorus compound is introduced, etc. Can be mentioned. These may be used alone or in combination of two or more. Among these, biphenylaralkyl type epoxy resin and α-naphthol / cresol novolac type epoxy resin are preferable from the viewpoint of heat resistance and flame retardancy.

When the thermosetting resin composition contains the thermosetting resin (d), the content thereof is 1 to 45 parts by mass with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. Preferably, 2 to 40 parts by mass is more preferable, and 3 to 35 parts by mass is further preferable.

<Curing accelerator (e)>
The thermosetting resin composition may further contain a curing accelerator (e).
Examples of the curing accelerator (e) include organic metal salts such as zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, bisacetylacetonate cobalt (II), and trisacetylacetonate cobalt (III); Examples thereof include imidazoles and derivatives thereof; organic phosphorus compounds; secondary amines; tertiary amines; quaternary ammonium salts and the like. These may be used alone or in combination of two or more. Among these, imidazoles and derivatives thereof are preferable from the viewpoint of heat resistance, flame retardancy and adhesive strength with a metal circuit, and organic phosphorus compounds are preferable from the viewpoint of low thermal expansion.
A commercially available product may be used as the curing accelerator (e). Examples of commercially available products include isocyanate mask imidazole (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., trade name: G-8009L), triphenylphosphine triphenylborane (manufactured by Hokuko Chemical Industry Co., Ltd., trade name: TPP-S) and the like. ..
When the thermosetting resin composition contains the curing accelerator (e), the content thereof is 0.1 to 10 parts by mass with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. Is preferable, 0.3 to 5 parts by mass is more preferable, and 0.5 to 2 parts by mass is further preferable. When the content of the curing accelerator (e) is 0.1 parts by mass or more, heat resistance, flame retardancy and copper foil adhesiveness tend to be excellent, and when it is 10 parts by mass or less, heat resistance and aging It tends to be excellent in stability and press formability.

<Inorganic filler (f)>
The thermosetting resin composition may further contain an inorganic filler (f).
Examples of the inorganic filler (f) include silica, alumina, titanium oxide, mica, beryllia, barium titanate, potassium titanate, strontium titanate, calcium titanate, aluminum carbonate, magnesium hydroxide, aluminum hydroxide, and silicate. Aluminum oxide, calcium carbonate, calcium silicate, magnesium silicate, silicon nitride, boron nitride, clay such as calcined clay, talc, aluminum borate, silicon carbide, quartz powder, short glass fibers, fine glass powder, hollow glass, etc. Can be mentioned. As the glass, E glass, T glass, D glass and the like are preferably mentioned. These may be used alone or in combination of two or more.
Among these, silica is preferable from the viewpoint of dielectric properties, heat resistance and low thermal expansion. Examples of silica include precipitated silica produced by a wet method and having a high water content, and dry silica produced by a dry method and containing almost no bound water or the like. Dry silica is further classified into crushed silica, fumed silica, molten spherical silica, and the like, depending on the manufacturing method. Among these, fused spherical silica is preferable from the viewpoint of low thermal expansion and fluidity when filled in a resin.

The average particle size of the inorganic filler (f) is preferably 0.1 to 10 μm, more preferably 0.3 to 8 μm, and even more preferably 0.3 to 3 μm. When the average particle size is 0.1 μm or more, the fluidity when highly filled in the resin tends to be maintained well, and when it is 10 μm or less, the mixing probability of coarse particles is reduced and defects caused by coarse particles are deteriorated. There is a tendency that the occurrence can be suppressed. Here, the average particle size is the particle size of a point corresponding to a volume of 50% when the cumulative frequency distribution curve by the particle size is obtained with the total volume of the particles as 100%, and the laser diffraction scattering method is used. It can be measured with the particle size distribution measuring device or the like.
The inorganic filler (f) may be surface-treated with a coupling agent. The method of surface treatment with a coupling agent may be a method of surface-treating the inorganic filler (f) before compounding by a dry method or a wet method, and the surface-untreated inorganic filler (f) may be treated with another inorganic filler (f). A so-called integral blend treatment method may be used in which a silane coupling agent is added to the composition after blending with the components to obtain a composition.
Examples of the coupling agent include a silane-based coupling agent, a titanate-based coupling agent, a silicone oligomer and the like.

When the thermosetting resin composition contains the inorganic filler (f), the content thereof is preferably 20 to 300 parts by mass with respect to 100 parts by mass of the solid content of the resin component in the thermosetting resin composition. , 50 to 250 parts by mass is more preferable, and 70 to 200 parts by mass is further preferable. When the content of the inorganic filler (f) is within the above range, moldability and low thermal expansion are good.

<Other ingredients>
The thermosetting resin composition of the present invention has an organic filler, a flame retardant, an ultraviolet absorber, an antioxidant, a photopolymerization initiator, a fluorescent whitening agent, and an adhesive property improvement to the extent that the thermosetting property is not impaired. It may contain an agent or the like.

Examples of the organic filler include resin fillers made of polyethylene, polypropylene, polystyrene, polyphenylene ether resin, silicone resin, tetrafluoroethylene resin and the like; acrylic acid ester resin, methacrylic acid ester resin, conjugated diene resin and the like. Examples thereof include a resin filler having a core-shell structure having a core layer in a rubber state and a shell layer in a glass state made of an acrylic acid ester resin, a methacrylic acid ester resin, an aromatic vinyl resin, a vinyl cyanide resin and the like.

Examples of the flame retardant include halogen-containing flame retardants containing bromine, chlorine and the like; phosphorus-based flame retardants such as triphenyl phosphate, tricresyl phosphate, trisdichloropropyl phosphazene, phosphoric acid ester compounds and red phosphorus; Nitrogen-based flame retardants such as guanidine acid, melamine sulfate, melamine polyphosphate, and melamine cyanurate; phosphazene-based flame retardants such as cyclophosphazene and polyphosphazene; and inorganic flame retardants such as antimony trioxide.

Examples of the ultraviolet absorber include benzotriazole-based ultraviolet absorbers.
Examples of the antioxidant include a hindered phenol-based antioxidant, a hindered amine-based antioxidant and the like.
Examples of the photopolymerization initiator include benzophenones, benzyl ketals, thioxanthone-based photopolymerization initiators and the like.
Examples of the fluorescent whitening agent include a fluorescent whitening agent of a stilbene derivative.
Examples of the adhesiveness improving agent include urea compounds such as ureasilane and the coupling agent.

The thermosetting resin composition may be in the state of a varnish in which each component is dissolved or dispersed in an organic solvent so that it can be easily used in the production of a prepreg or the like.

Examples of the organic solvent include alcohol solvents such as methanol, ethanol, propanol, butanol, methyl cellosolve, butyl cellosolve and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; butyl acetate and propylene. Ester-based solvents such as glycol monomethyl ether acetate; Ether-based solvents such as tetrahydrofuran; Aromatic solvents such as toluene, xylene and mesitylene; Nitrogen atom-containing solvents such as dimethylformamide, dimethylacetamide and N-methylpyrrolidone; Dimethylsulfoxide and the like Examples include a sulfur atom-containing solvent. These may be used alone or in combination of two or more.
Among these, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl cellosolve, and propylene glycol monomethyl ether are preferable from the viewpoint of solubility of each component, methyl ethyl ketone is more preferable, and methyl isobutyl from the viewpoint of low toxicity. Ketones, cyclohexanone and propylene glycol monomethyl ethers are more preferred.
The solid content concentration of the varnish is preferably 40 to 90% by mass, more preferably 50 to 80% by mass. When the solid content concentration of the varnish is within the above range, good coatability can be maintained and a prepreg having an appropriate content of the thermosetting resin composition can be obtained.

Using the thermosetting resin composition of the present invention, a prepreg and a copper-clad laminate were prepared by the method shown in Examples, and the coefficient of thermal expansion measured by the method shown in Examples using the copper-clad laminate was From the viewpoint of low warpage, 9 ppm / ° C. or lower is preferable, 8 ppm / ° C. or lower is more preferable, and 7 ppm / ° C. or lower is further preferable. The lower limit of the coefficient of thermal expansion is, for example, 3 ppm / ° C. or higher, and may be 4 ppm / ° C. or higher.
Using the thermosetting resin composition of the present invention, a prepreg and a copper-clad laminate were produced by the method shown in Examples, and the flexural modulus measured by the method shown in Examples using the copper-clad laminate was From the viewpoint of low warpage, 25 GPa or less is preferable, 20 GPa or less is more preferable, and 18 GPa or less is further preferable. The lower limit of the flexural modulus is, for example, 5 GPa or more, and may be 10 GPa or more.

[Prepreg for coreless board]
The prepreg for a coreless substrate of the present invention (hereinafter, also simply referred to as "prepreg") contains the thermosetting resin composition of the present invention.
The prepreg of the present invention can be produced, for example, by impregnating a fiber base material with the thermosetting resin composition and semi-curing (B-staged) by heating or the like.
As the fiber base material, well-known materials used for various laminated plates for electrical insulating materials can be used. Examples of the material include inorganic fibers such as E glass, S glass, low dielectric glass, and Q glass; organic fibers such as low dielectric glass polyimide, polyester, and tetrafluoroethylene; and mixtures thereof. In particular, from the viewpoint of dielectric properties, inorganic fibers are preferable, and low-dielectric glass and Q glass are more preferable.
These fiber substrates have shapes such as woven fabrics, non-woven fabrics, robinks, chopped strand mats, and surfaced mats.
The material and shape of the fiber base material are appropriately selected depending on the intended use and performance of the molded product, and if necessary, the fiber base material may be one type of material and one type of shape, or two types. It may be a fiber base material made of the above materials, or may be a fiber base material having two or more types of shapes.
The thickness of the fiber base material is, for example, 10 μm to 0.5 mm, preferably 10 to 100 μm, more preferably 10 to 80 μm, and further preferably 15 to 50 μm from the viewpoint of enabling low warpage and high-density wiring. preferable. From the viewpoint of heat resistance, moisture resistance, processability, etc., these fiber base materials are preferably surface-treated with a silane coupling agent or the like, or mechanically opened.

The content of the thermosetting resin composition in the prepreg of the present invention is, for example, 20 to 90% by mass in the total solid content of the prepreg, and is 50 from the viewpoint of improving low warpage and embedding property of wiring. It is preferably ~ 85% by mass, more preferably 60-80% by mass.

The thickness of the prepreg of the present invention is, for example, 10 μm to 0.5 mm, preferably 10 to 100 μm, more preferably 10 to 80 μm, from the viewpoint of reducing warpage and enabling high-density wiring. 50 μm is more preferable.

The prepreg of the present invention is, for example, at a temperature of 100 to 200 ° C. after impregnating a fiber base material with a thermosetting resin composition so that the content of the thermosetting resin composition in the prepreg is within the above range. It can be produced by heating and drying for 1 to 30 minutes and semi-curing (B-stage).

[Coreless substrate and its manufacturing method]
The coreless substrate of the present invention contains an insulating layer formed by using the prepreg for a coreless substrate of the present invention.
In the coreless substrate of the present invention, for example, a build-up layer in which conductor layers and insulating layers are alternately laminated by using the prepreg of the present invention is formed on a support (core substrate), and then the support is formed. It can be manufactured by a method of separation. The method for forming the build-up layer is not particularly limited, and a known method can be adopted. For example, the build-up layer can be formed by the following method (see FIG. 1).
First, the prepreg 2 of the present invention is placed on the support (core substrate) 1. The prepreg 2 may be arranged after the adhesive layer is arranged on the support (core substrate) 1. Then, the prepreg 2 is heat-cured to form an insulating layer. Next, after forming the via hole 3 by a drill cutting method, a laser processing method using a YAG laser, a CO ₂ laser, or the like, a surface roughening treatment and a desmear treatment are performed as necessary. Subsequently, the circuit pattern 4 is formed by a subtractive method, a full additive method, a semi-additive method (SAP: Semi Additive Process), a modified semi-additive method (m-SAP: modified Semi Additive Process), or the like. By repeating the above process, the build-up layer 5 is formed. A coreless substrate can be obtained by separating the formed build-up layer 5 from the support (core substrate) 1. The screw-up layer 5 may be formed on one side of the support (core substrate) 1 or on both sides.
The coreless substrate of the present invention contains one or more insulating layers obtained by curing the prepreg of the present invention, and may include an insulating layer obtained by curing a prepreg, a resin film, or the like other than the prepreg of the present invention. Good.
The thickness of the coreless substrate of the present invention is usually small because it does not have a core substrate, and specifically, it is preferably 15 to 200 mm, more preferably 30 to 150 mm, still more preferably 35 to 100 mm.

[Semiconductor package]
The semiconductor package of the present invention is formed by mounting a semiconductor element on the coreless substrate of the present invention. For example, the semiconductor package of the present invention is manufactured by mounting a semiconductor element such as a semiconductor chip or a memory at a predetermined position on the coreless substrate.

Next, the present invention will be described in more detail with reference to the following examples, but these examples do not limit the present invention.
The performance of the copper-clad laminates obtained in the following examples was measured and evaluated by the following methods.

(1) Warpage amount The warp amount of the substrate produced in each example was measured using a surface shape measuring device (manufactured by AKROMETRIX, trade name: Thermoray PS200, shadow moire analysis). The size of the substrate was 40 mm × 40 mm, and a substrate having a semiconductor element having a size of 10 mm × 10 mm × 100 μm mounted in the center of the substrate was used as the evaluation substrate. The measurement area was 36 mm × 36 mm. The amount of warpage when the evaluation substrate was heated from room temperature to 260 ° C. and then cooled to 50 ° C. was measured.

(2) Dimensional change rate As shown in FIG. 2, the copper-clad laminates obtained in each example were cut out to a size of 330 mm × 240 mm, and the evaluation substrate had a diameter of 1.3 mm at 10 mm from each of the vertical and horizontal ends. I made four holes. Next, with copper attached, the shortest distance between holes adjacent to each other in the longitudinal direction (vertical direction) and the shortest distance between holes adjacent to each other in the lateral direction (horizontal direction) are determined by an image measuring machine (Mitutoyo Co., Ltd.). Manufactured by, trade name: QVH4A Apex 404) was used for each measurement. Next, the copper foil was removed by immersing the evaluation substrate in a copper etching solution, and then the shortest distance between the holes was measured by the same method. From the amount of change in the inter-hole distance before and after etching, the vertical and horizontal dimensional change rate (%) [(amount of change in inter-hole distance before and after etching / inter-hole distance before etching) x 100] is calculated, and the length is calculated. The average of the dimensional change rates in the direction and the lateral direction was taken as the dimensional change rate after etching.
Subsequently, the evaluation substrate from which the copper foil had been removed by etching was heated in a dryer at 230 ° C. for 60 minutes, and then the shortest distance between the holes was measured by the same method. From the amount of change in the distance between holes before and after heating, the rate of change in dimensions in the vertical and horizontal directions (%) [(amount of change in distance between holes before and after heating / distance between holes before heating) x 100] is calculated, and the length is calculated. The average of the dimensional change rates in the direction and the lateral direction was taken as the dimensional change rate after heating.

(3) Coefficient of thermal expansion By removing the copper foil by immersing the copper-clad laminate obtained in each example in a copper etching solution, vertical (X direction) 5 mm x horizontal (Y direction) 5 mm x thickness (Z direction) An evaluation substrate of 0.15 mm was prepared, and thermomechanical analysis was performed by a compression method using a TMA test apparatus (manufactured by DuPont, trade name: TMA2940). After the evaluation substrate was mounted on the apparatus in the X direction, the measurement was carried out twice continuously under the measurement conditions of a load of 5 g and a heating rate of 10 ° C./min. The average coefficient of thermal expansion from 30 ° C. to 100 ° C. in the second measurement was calculated and used as the value of the coefficient of thermal expansion.

(4) Copper foil adhesiveness (copper foil peel strength)
By immersing the copper-clad laminates obtained in each example in a copper etching solution, an outer copper layer is formed to a width of 3 mm, and one end of the copper-clad laminate is peeled off at the interface between the outer copper layer and the insulating layer, gripped with a gripper, and pulled. Using a testing machine, the copper foil adhesiveness (copper foil peel strength) when peeled off at room temperature was measured at a tensile speed of about 50 mm / min in the vertical direction. The coreless substrate preferably has a copper foil peel strength of 0.5 kN / m or more.

(5) Glass transition temperature (Tg)
By removing the copper foil by immersing the copper-clad laminate obtained in each example in a copper etching solution, an evaluation substrate having a length (X direction) of 5 mm x a width (Y direction) of 5 mm x a thickness (Z direction) of 0.15 mm. Was prepared, and thermomechanical analysis was performed by a compression method using a TMA test apparatus (manufactured by DuPont, trade name: TMA2940). After the evaluation substrate was mounted on the apparatus in the X direction, the measurement was carried out twice continuously under the measurement conditions of a load of 5 g and a heating rate of 10 ° C./min. The Tg indicated by the intersection of the tangents having different thermal expansion curves in the second measurement was obtained and used as an index of heat resistance. The higher the Tg, the better the heat resistance.

(6) Bending Elastic Modulus A 50 mm × 25 mm evaluation substrate from which the copper foil was removed was produced by immersing the copper-clad laminates obtained in each example in a copper etching solution, and the Tencilon universal testing machine “RTC-1350A” (stock). The flexural modulus was measured under the conditions of a crosshead speed of 1 mm / min and a span distance of 20 mm using (manufactured by Orientec Co., Ltd.). The higher the value, the higher the rigidity.

(7) Desmear Weight Reduction A 40 mm × 40 mm evaluation substrate from which the copper foil was removed by immersing the copper-clad laminate in a copper etching solution was subjected to desmear treatment by the process shown in Table (A). The chemical solution used was manufactured by Attec. The amount of weight loss after the desmear treatment was calculated with respect to the dry weight before the desmear treatment, and this was used as an index of the desmear resistance. The smaller the amount of desmear weight reduction, the better the desmear resistance.

Production Example 1: Production of siloxane-modified polyimide (X-1) In a reaction vessel with a volume of 2 liters that can be heated and cooled equipped with a thermometer, a stirrer, and a water content meter with a reflux cooling tube, both terminal amino-modified siloxane compounds ( Manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name: X-22-161A, functional group equivalent of amino group: 800 g / mol, (a) component) 72 g, and bis (4-maleimidephenyl) methane (KAI Kasei Co., Ltd.) 252 g of (BMI, component (b)) and 270 g of propylene glycol monomethyl ether were added and reacted at 110 ° C. for 3 hours to obtain a siloxane-modified polyimide (X-1) -containing solution.

Production Example 2: Production of siloxane-modified polyimide (X-2) In a reaction vessel with a volume of 2 liters that can be heated and cooled equipped with a thermometer, a stirrer, and a moisture quantifier with a reflux condenser, both terminal amino-modified siloxane compounds ( Manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name: X-22-161B, functional group equivalent of amino group: 1,500 g / mol, (a) component) 85 g and 2,2-bis [4- (4-maleimide phenoxy). ) Phenyl] Propane (manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name: BMI-4000, component (b)) 289 g and propylene glycol monomethyl ether 270 g are added and reacted at 110 ° C. for 3 hours to produce a siloxane-modified polyimide () X-2) A containing solution was obtained.

Production Example 3: Production of siloxane-Modified Maleimide (X-3) In a reaction vessel with a volume of 2 liters that can be heated and cooled equipped with a thermometer, a stirrer, and a moisture meter with a reflux cooling tube, both terminal amino-modified siloxane compounds ( Manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name: X-22-1660B-3, functional group equivalent of amino group: 2,200 g / mol, component (a)) 100 g, and 2,2-bis [4- (4- (4- (4- (4- (4-) Maleimide phenoxy) phenyl] propane (manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name: BMI-4000, component (b)) 289 g and propylene glycol monomethyl ether 270 g are added and reacted at 110 ° C. for 3 hours to modify siloxane. A polyimide (X-3) -containing solution was obtained.

Examples 1-12, Comparative Examples 1-5
Each component shown below is mixed at the blending ratio shown in Tables 1 to 3 (the unit of the numerical value in the table is a mass part, and in the case of a solution, it is a solid content equivalent amount), and methyl ethyl ketone is added to the solvent. A uniform varnish having a solid content concentration of 65% by mass was prepared. Next, this varnish was impregnated and coated on a T glass cloth having a thickness of 25 μm, and dried by heating at 130 ° C. for 10 minutes to obtain a prepreg having a thermosetting resin composition content of 68% by mass.
Six of these prepregs were stacked, and 3 μm electrolytic copper foils were arranged one above the other, and pressed at a pressure of 2.5 MPa and a temperature of 240 ° C. for 60 minutes to obtain a copper-clad laminate. Tables 1 to 3 show the evaluation results obtained according to the measurement method for the obtained copper-clad laminate.

[Amino-modified siloxane compound (a)]
X-22-161A: Both-terminal amino-modified siloxane compound [manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name, functional group equivalent of amino group: 800 g / mol]
X-22-161B: Both-terminal amino-modified siloxane compound [manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name, functional group equivalent of amino group: 1,500 g / mol]
X-22-1660B-3: Both-terminal amino-modified siloxane compound [manufactured by Shin-Etsu Chemical Industry Co., Ltd., trade name, functional group equivalent of amino group: 2,200 g / mol]

[Maleimide compound (b) having at least two N-substituted maleimide groups in one molecule]
-BMI: Bis (4-maleimidephenyl) methane [manufactured by Keiai Kasei Co., Ltd., trade name]
BMI-4000: 2,2-bis [4- (4-maleimide phenoxy) phenyl] propane [manufactured by Daiwa Kasei Kogyo Co., Ltd., trade name]

[Thermoplastic elastomer (c)]
Epofriend (registered trademark) CT-310: Epoxy-modified styrene-butadiene copolymer resin [manufactured by Daicel Corporation, trade name]
-Tough Tech (registered trademark) M1913: Carboxylic acid-modified hydrogenated styrene-butadiene copolymer resin [Asahi Kasei Chemicals Co., Ltd., trade name]

[Siloxane-modified polyimide (X)]
X-1: Siloxane-modified polyimide (X-1) -containing solution prepared in Production Example 1-X-2: Siloxane-modified polyimide (X-2) -containing solution prepared in Production Example 2-X-3: Production Example 3 Siloxane-modified polyimide (X-3) -containing solution prepared in

[Thermosetting resin (d)]
-NC-7000-L: α-naphthol / cresol novolac type epoxy resin [manufactured by Nippon Kayaku Co., Ltd., trade name]
-NC-3000-H: Biphenyl aralkyl type epoxy resin [manufactured by Nippon Kayaku Co., Ltd., trade name]

[Curing accelerator (e)]
-G-8009L: Isocyanate mask imidazole [manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name]
-TPP-S: Triphenylphosphine Triphenylborane [manufactured by Hokuko Chemical Co., Ltd., trade name]

[Inorganic filler (f)]
-SC2050-KNK: Spherical fused silica [manufactured by Admatex Co., Ltd., trade name, average particle size: 0.5 μm]

As is clear from Tables 1 and 2, the copper-clad laminates of Examples 1 to 12 obtained by using the thermosetting resin composition of the present invention have a warp amount, a dimensional change rate, and a thermal expansion rate. , Copper foil adhesiveness, glass transition temperature, flexural modulus and desmear weight reduction amount are well-balanced and excellent, and in particular, it can be seen that the warp amount and the dimensional change rate are highly compatible.
On the other hand, as is clear from Table 3, the copper-clad laminates of Comparative Examples 1, 2 and 5 not containing the amino-modified siloxane compound (a) and the copper of Comparative Examples 3 and 4 not containing the maleimide compound (b). No tension laminated plate simultaneously satisfies all the characteristics of warpage amount, dimensional stability, thermal expansion rate, copper foil adhesiveness, glass transition temperature, flexural modulus and desmear weight reduction amount, and in particular, the warpage amount and thermal expansion. It is inferior in rate. Therefore, it can be seen that the thermosetting resin composition of the present invention has a small warp when made into a coreless substrate and has a high level of dimensional stability required for a coreless substrate.

The thermosetting resin composition for a coreless substrate of the present invention has a high degree of both low warpage and dimensional stability required for a coreless substrate, and thus has a high density and a high number of layers. It is suitable for manufacturing coreless substrates, and is preferably used for wiring boards of electronic devices used such as computers and information device terminals that process a large amount of data at high speed.

1 Support (core substrate)
2 prepreg (insulation layer)
3 Via hole 4 Circuit pattern 5 Build-up layer 6 Coreless board

Claims (11)

A coreless substrate containing a siloxane compound (a) having at least two primary amino groups in one molecule and a maleimide compound (b) having at least two N-substituted maleimide groups in one molecule. Thermosetting resin composition for use. A siloxane that is a reaction product of a siloxane compound (a) having at least two primary amino groups in one molecule and a maleimide compound (b) having at least two N-substituted maleimide groups in one molecule. A thermosetting resin composition for a coreless substrate, which contains a modified polyimide (X). The thermosetting for a coreless substrate according to claim 1 or 2, wherein the siloxane compound (a) having at least two primary amino groups in one molecule is represented by the following general formula (1). Sex resin composition.

(In the general formula (1), R ^a1 , R ^a2 , R ^a3 and R ^a4 each independently represent an alkyl group, a phenyl group or a substituted phenyl group. X ^a1 and X ^a2 are each independently divalent organic. Represents a group, m is an integer from 1 to 50.) The thermosetting resin composition for a coreless substrate according to any one of claims 1 to 3, further comprising a thermoplastic elastomer (c). The thermosetting resin composition for a coreless substrate according to any one of claims 1 to 4, further comprising a thermosetting resin (d). The thermosetting resin composition for a coreless substrate according to any one of claims 1 to 5, further comprising a curing accelerator (e). The thermosetting resin composition for a coreless substrate according to any one of claims 1 to 6, further comprising an inorganic filler (f). A prepreg for a coreless substrate, which comprises the thermosetting resin composition according to any one of claims 1 to 7. A coreless substrate containing an insulating layer formed by using the prepreg for a coreless substrate according to claim 8. A semiconductor package in which a semiconductor element is mounted on the coreless substrate according to claim 9. A method for manufacturing a coreless substrate, wherein a build-up layer formed by alternately laminating conductor layers and insulating layers is formed on a support, and then the build-up layer is separated from the support. A method for manufacturing a coreless substrate, wherein at least one layer of the above is formed by using the prepreg for a coreless substrate according to claim 8.