JP2005097524A - Resin composition, prepreg and laminated sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a resin composition and a prepreg, and to prepare a laminated sheet keeping mechanical and electric connection reliability in hot and humid atmosphere. <P>SOLUTION: The resin composition is used for impregnating it into a base material and forming the sheet-like prepreg and comprises a cyanate resin and/or its prepolymer and an ion exchanger. The prepreg is obtained by impregnating the resin composition into the base material. The laminated sheet is obtained by forming one or more sheets of the prepreg. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a resin composition, a prepreg, and a laminate.

  In the semiconductor field, a trend of shifting from conventional surface mounting to area mounting is progressing due to progress in high-density mounting technology, and new packages such as BGA (ball grid array) and CSP (chip scale package) are increasing. The speed of information transmission is also increasing. For this reason, the rigid substrate for interposers has attracted more attention than before, and the demand for a high heat resistance, low thermal expansion and low dielectric substrate has increased.

  Furthermore, in recent years, with the demand for higher functionality of electronic devices, etc., the integration of electronic components has been increased, and further, the mounting of high density has been progressing. More than ever, miniaturization and higher density are progressing. Many build-up multilayer wiring boards have been adopted as a countermeasure for increasing the density of such printed wiring boards.

  However, in the method using the build-up multilayer wiring board, since the interlayer connection is made by fine vias, the connection strength is lowered, so that it is difficult to maintain the mechanical and electrical connection reliability in a high temperature and high humidity atmosphere. There was a point.

In order to achieve such an object, high heat resistance and low linear expansion of the resin used for the substrate are effective means, and cyanate resin is used as a resin having excellent heat resistance. (For example, see Patent Documents 1 and 2)
Japanese Patent Laid-Open No. 2002-194221 JP 2000-239396 A

  The present invention provides a resin composition, a prepreg, and a laminate used for manufacturing a printed wiring board capable of maintaining mechanical and electrical connection reliability in a high-temperature and high-humidity atmosphere.

Such an object is achieved by the present invention described in the following (1) to (9).
(1) A resin composition used for impregnating a base material to form a sheet-like prepreg, which contains a cyanate resin and / or a prepolymer thereof, and an ion exchanger. Stuff.
(2) The resin composition according to the above (1), which contains a thermosetting resin different from the cyanate resin.
(3) The resin composition according to (2), wherein the thermosetting resin contains an epoxy resin and / or a phenol resin.
(4) The resin composition according to any one of (1) to (3), further including an inorganic filler.
(5) The resin composition according to any one of (1) to (4), wherein the ion exchanger includes an inorganic ion exchanger.
(6) The resin composition according to (5), wherein the inorganic ion exchanger has an average particle size of 0.02 to 5 μm.
(7) The resin composition according to any one of (1) to (6), wherein the content of the ion exchanger is 0.5 to 3 parts by weight with respect to 100 parts by weight of the resin composition.
(8) A prepreg obtained by impregnating a base material with the resin composition according to any one of (1) to (7).
(9) A laminate obtained by molding one or more prepregs as described in (8) above.

ADVANTAGE OF THE INVENTION By this invention, the resin composition, prepreg, and laminated board which are used for manufacture of the printed wiring board which can hold | maintain mechanical and electrical connection reliability in a high-temperature, humid atmosphere can be provided.
Also, when a resin different from the cyanate resin is used together with the cyanate resin, the moisture resistance is improved, and further, when an inorganic filler is used, it is used for manufacturing a printed wiring board having improved thermal expansion and low linear expansion. Resin compositions, prepregs and laminates can be provided.

Hereinafter, the resin composition, prepreg and laminate of the present invention will be described in detail.
The resin composition of the present invention is a resin composition used for impregnating a base material to form a sheet-like prepreg, and includes a cyanate resin and / or a prepolymer thereof, and an ion exchanger. It is what.
Moreover, the prepreg of the present invention is characterized in that a base material is impregnated with the above-mentioned resin composition.
Moreover, the laminated board of the present invention is formed by molding one or more of the above-described prepregs.

Hereinafter, the resin composition of the present invention will be described.
In the resin composition of the present invention, a cyanate resin is used. Thereby, dielectric characteristics can be improved.
The cyanate resin is not particularly limited and may be any resin containing a cyanate group. For example, a bisphenol type such as a novolak type cyanate resin, a bisphenol A type cyanate resin, a bisphenol E type cyanate resin, or a bisphenol F type cyanate resin. Examples include cyanate resins. Among these, it is preferable that the novolak cyanate resin represented by the general formula (I) is included. Thereby, a glass transition temperature can be made high and the resin characteristic and flame retardance after hardening can be improved more.

  Since the cyanate resin does not generate a functional group having a large polarizability such as a hydroxyl group by a curing reaction, the dielectric property is very excellent. Moreover, since it has a rigid chemical structure, it has excellent heat resistance.

Moreover, what prepolymerized the said cyanate resin is preferably used in order to adjust a moldability and fluidity | liquidity, and is contained in the cyanate resin of this invention.
The prepolymerization is usually performed by heating and melting. In the present invention, the prepolymer refers to one having a trimerization rate of 20 to 50% by weight, for example.
The trimerization rate can be determined using, for example, an infrared spectroscopic analyzer. A cyanate resin and a prepolymerized cyanate resin may be used in combination.

  Although content of the said cyanate resin is not specifically limited, 5-60 weight part is preferable among 100 weight part of resin compositions, and 10-50 weight part is especially preferable. If the content is less than the lower limit, the effect of improving the dielectric properties may be reduced, and if the content exceeds the upper limit, it may be difficult to control the reaction and formability may be reduced.

In the resin composition of the present invention, an ion exchanger is used. Thereby, the mechanical and electrical connection reliability at high temperature and high humidity can be maintained.
Examples of the ion exchanger include a substance having a polymer acid to which an acidic group such as an acidic hydroxyl group, a carboxyl group, and a sulfone group is bonded, a metal hydrated oxide called an inorganic ion exchanger, and the like.
Specific examples of inorganic ion exchangers include hydrated oxides such as Si, Ti, Nb, Sn, Zr, Al, Sb, and Fe, and phosphates with tetravalent metals such as Zr, Sn, and Ti, Examples thereof include synthetic zeolite.
Among these, an inorganic ion exchanger is preferable. Thereby, the mechanical and electrical connection reliability at high temperature and high humidity can be further maintained.

The use of the ion exchanger in the present invention provides a new function different from that conventionally used for preventing metal migration.
Conventional ion exchangers capture ionic impurities such as chloride ions, sodium ions, iron ions, hydrolyzable chlorine, hydrolyzable bromine remaining in the PPM order in the resin, and by applying a voltage, It has been used to trap metal ions that move as ions and prevent migration between patterns.

  In contrast, when the present inventors use a cyanate resin and an ion exchanger in combination, the triazine ring produced by curing the cyanate resin is prevented from being decomposed by an acidic substance (for example, a phenol resin). I found what I could do. Therefore, by using a cyanate resin and an ion exchanger in combination, it is possible to maintain mechanical and electrical connection reliability at high temperature and high humidity, which could not be obtained by conventional techniques.

In the present invention, among the inorganic ion exchangers, it is preferable to use an anion exchange type or both ion exchange type inorganic ion exchanger, and it is most preferable to use an anion exchange type inorganic ion exchanger. An anion exchange type inorganic ion exchanger generates hydroxide ions after ion exchange. Thereby, it can prevent that resin cured material becomes acidic, and can suppress that the triazine ring which a cyanate resin hardens | cures and produces | generates is decomposed | disassembled by an acid.
Examples of such anion exchange type inorganic ion exchangers include bismuth, zirconium, and magnesium-aluminum inorganic ion exchangers.

  Although content of the said inorganic ion exchanger is not specifically limited, 0.5-3 weight part is preferable with respect to 100 weight part of resin compositions, and 1-2 weight part is especially preferable. If the content is less than the lower limit, the effect of suppressing the decomposition of the triazine ring may be reduced, and if the content exceeds the upper limit, the inorganic ion exchanger may be precipitated in the varnish.

Although it does not specifically limit as an average particle diameter of the inorganic ion exchanger used by this invention, It is preferable that it is 0.02-5 micrometers. More preferably, it is 0.02-3 micrometers. Thereby, the said effect can be expressed effectively.
In particular, when a resin having an average particle size of 0.02 to 0.5 μm is used, when preparing a resin varnish, the inorganic ion exchanger can be prevented from settling in the resin varnish and workability can be improved. it can.

In the resin composition of this invention, it is preferable to use resin different from cyanate resin with cyanate resin. Thereby, the moisture resistance characteristic of cyanate resin can be supplemented.
Examples of the resin different from the cyanate resin include an epoxy resin and a composition thereof, a polyimide resin and a composition thereof, a phenol resin and a composition thereof, a polyester resin and a thermosetting resin such as a composition thereof, a phenoxy resin, and a polyphenylene oxide. Examples thereof include thermoplastic resins such as resins and polyethersulfone resins.
Among these, it is preferable to use a thermosetting resin. Thereby, the adhesiveness of a metal and resin and plating adhesiveness can be improved by this.

Examples of the epoxy resin include phenol novolac type epoxy resins, bisphenol type epoxy resins, naphthalene type epoxy resins, arylalkylene type epoxy resins and the like. Among these, aryl alkylene type epoxy resins are preferable. Thereby, moisture absorption solder heat resistance can be improved.
Examples of the aryl alkylene type epoxy resin include a xylylene type epoxy resin and a biphenyl dimethylene type epoxy resin. Among these, a biphenyl dimethylene type epoxy resin is preferable. Thereby, dimensional stability can be improved.

  Examples of the phenol resin include novolak-type phenol resins, resol-type phenol resins, and arylalkylene-type phenol resins. Among these, arylalkylene type phenol resins are preferable. Thereby, moisture absorption solder heat resistance can be improved further. Examples of the aryl alkylene type phenol resin include a xylylene type phenol resin and a biphenyl dimethylene type phenol resin. Among these, a biphenyl dimethylene type resin is preferable. Thereby, the adhesiveness of a metal and resin can be improved.

  Although content of resin different from the said cyanate resin is not specifically limited, 3-55 weight part is preferable among 100 weight part of resin compositions, and 5-40 weight part is especially preferable.

  When using the said epoxy resin as resin different from the said cyanate resin, the content is not specifically limited, 3-35 weight part is preferable among 100 weight part of resin compositions, and 5-30 weight part is especially preferable. If the content is less than the lower limit, the moisture resistance of the resulting product may be reduced, and if it exceeds the upper limit, the heat resistance may be reduced.

  When the phenol resin is used as a resin different from the cyanate resin, the content is not particularly limited, but is preferably 0.1 to 20 parts by weight, particularly 0.5 to 10 parts by weight, out of 100 parts by weight of the resin composition. Part is preferred. When the content is less than the lower limit, the heat resistance may be reduced, and when the content exceeds the upper limit, the characteristics of low thermal expansion may be impaired.

The resin composition of the present invention preferably contains an inorganic filler. Thereby, low thermal expansion and improvement in flame retardance can be achieved.
Further, the elastic modulus can be improved by a combination of the above-described cyanate resin and / or its prepolymer and an inorganic filler.
Examples of the inorganic filler include talc (particularly calcined talc), alumina, glass, silica, mica and the like. Among these, silica is preferable, and fused silica is preferable in that it has excellent low expansibility. The shape is crushed and spherical, but in order to reduce the melt viscosity of the resin composition in order to ensure the impregnation property to the glass substrate, a usage method adapted to the purpose such as using spherical silica is adopted. .
As the inorganic filler, it is particularly preferable to use spherical fused silica. Thereby, the filling property of the inorganic filler in the resin composition can be improved.

  The average particle size of the inorganic filler is not particularly limited, but is preferably 0.01 to 5 μm, and particularly preferably 0.2 to 2 μm. When the resin varnish is prepared using the resin composition of the present invention when the particle size of the inorganic filler is less than the lower limit, the viscosity of the varnish is increased, so that the workability during prepreg production is reduced, The impregnation property of the resin composition with respect to the substrate may be lowered. When the upper limit is exceeded, phenomena such as sedimentation of the inorganic filler may occur in the varnish.

  The content of the inorganic filler is preferably 30 to 70 parts by weight, particularly preferably 40 to 60 parts by weight, out of 100 parts by weight of the resin composition. If the content is less than the lower limit, the effect of low thermal expansion and low water absorption may be reduced, and if the content exceeds the upper limit, moldability may be reduced due to a decrease in fluidity.

Although it does not specifically limit in the resin composition of this invention, It is preferable to contain a coupling agent further.
The coupling agent improves the heat resistance, particularly the solder heat resistance after moisture absorption, by uniformly fixing the resin and the filler to the substrate by improving the wettability of the interface between the resin and the inorganic filler. For blending.

  As the coupling agent, any of those usually used can be used, and among these, one kind selected from an epoxy silane coupling agent, a titanate coupling agent, an aminosilane coupling agent, and a silicone oil type coupling agent. It is preferable to use the above coupling agent. Thereby, wettability with the interface of an inorganic filler can be made high, and heat resistance can be improved more.

  Although content of the said coupling agent is not specifically limited, 0.05-3 weight part is preferable with respect to 100 weight part of inorganic fillers. When the content is less than the lower limit value, the inorganic filler may not be sufficiently coated and the effect of improving heat resistance may be reduced. When the content exceeds the upper limit value, the bending strength of the prepreg or the laminate is reduced. There is.

  The resin composition of this invention can add additives other than the said component in the range which does not impair a characteristic as needed. Examples of the additive include an antifoaming agent and a leveling agent.

Next, the prepreg will be described.
The prepreg of the present invention is obtained by impregnating a base material with the above resin composition.
Thereby, it is possible to obtain a prepreg suitable for manufacturing a printed wiring board excellent in various characteristics such as dielectric characteristics, mechanical and electrical connection reliability under high temperature and high humidity.
As a base material used by this invention, glass fiber base materials, such as a glass fiber cloth and a glass non-woven cloth, for example,
Alternatively, it is composed of an inorganic fiber substrate such as a fine cloth or a non-woven cloth containing an inorganic compound other than glass, an organic fiber such as an aromatic polyamide resin, a polyamide resin, an aromatic polyester resin, a polyester resin, a polyimide resin, or a fluororesin. An organic fiber base material etc. are mentioned. Among these base materials, glass fiber base materials represented by glass woven fabric are preferable in terms of strength and water absorption.

  Examples of the method of impregnating the base material with the resin composition obtained in the present invention include preparing a resin varnish using the resin composition of the present invention, immersing the base material in the resin varnish, and applying with various coaters. Examples thereof include a method and a spraying method. Among these, the method of immersing the base material in the resin varnish is preferable. Thereby, the impregnation property of the resin composition with respect to a base material can be improved. In addition, when a base material is immersed in a resin varnish, a normal impregnation coating equipment can be used.

The solvent used in the resin varnish desirably exhibits good solubility in the resin component in the resin composition, but a poor solvent may be used within a range that does not adversely affect the resin varnish. Examples of the solvent exhibiting good solubility include methyl ethyl ketone and cyclohexanone.
The solid content of the resin varnish is not particularly limited, but the solid content of the resin composition is preferably 40 to 80% by weight, and particularly preferably 50 to 65% by weight. Thereby, the impregnation property to the base material of a resin varnish can further be improved. A prepreg can be obtained by impregnating the base material with the resin composition and drying at a predetermined temperature, for example, 80 to 200 ° C.

Next, a laminated board is demonstrated.
The laminate of the present invention is formed by molding at least one prepreg described above. Thereby, the laminated board excellent in the dielectric property and the mechanical and electrical connection reliability in high temperature and high humidity can be obtained.
In the case of a single prepreg, a metal foil or film is stacked on both upper and lower surfaces or one surface. Two or more prepregs can be laminated. When two or more prepregs are laminated, a metal foil or film is laminated on the outermost upper and lower surfaces or one surface of the laminated prepreg. Next, a laminate can be obtained by heating and pressurizing a laminate of a prepreg and a metal foil. Although the temperature to heat is not specifically limited, 120-220 degreeC is preferable and especially 150-200 degreeC is preferable. Moreover, the pressure to pressurize is not particularly limited, but is preferably 2 to 5 MPa, and particularly preferably 2.5 to 4 MPa.

Examples of the metal constituting the metal foil include copper and a copper alloy, aluminum and an aluminum alloy, iron and an iron alloy, and the like.
Examples of the film include polyethylene and polypropylene.

Hereinafter, although an example and a comparative example explain the present invention, the present invention is not limited to this.
(Example 1)
(1) Preparation of resin varnish 15 parts by weight of novolak type cyanate resin (Lonza Japan Co., Ltd., Primaset PT-30, weight average molecular weight about 700), novolak type cyanate resin (Lonza Japan Co., Ltd., Primaset PT-60) , Weight average molecular weight of about 2600) 5 parts by weight, biphenyl dimethylene type epoxy resin (Nippon Kayaku Co., Ltd., NC-3000H, epoxy equivalent 275) 11 parts by weight, biphenyl dimethylene type phenol resin (Maywa Kasei Co., Ltd.) MEH-7851-3H, hydroxyl equivalent 230) 9 parts by weight and epoxy silane type coupling agent (Nihon Unicar Co., Ltd., A-187) 0.3 parts by weight were dissolved in methyl ethyl ketone at room temperature, and spherical fused silica (stock) Company Admatex, spherical fused silica, SO-32R, flat Particle size 1.5 [mu] m) were added 60 parts by weight, and stirred for 10 minutes using a high speed stirrer. To this, 1.5 parts by weight of an inorganic ion exchanger (manufactured by Toa Gosei Co., Ltd., IXE-700F, aluminum-magnesium inorganic ion exchanger, average particle size of about 1 μm) is added and stirred for 10 minutes using a high-speed stirrer. Thus, a resin varnish was obtained.

(2) Manufacture of prepreg The above-mentioned resin varnish is impregnated into a glass woven fabric (thickness 94 μm, manufactured by Nitto Boseki Co., Ltd., WEA-2116) and dried in a heating furnace at 150 ° C. for 2 minutes. About 50% by weight of prepreg was obtained.

(3) Manufacture of laminated plate Two-layer copper having a thickness of 0.2 mm is obtained by stacking two prepregs as described above, stacking 18 μm copper foil on both sides, and heating and pressing at a pressure of 4 MPa and a temperature of 200 ° C. for 2 hours. A tension laminate was obtained.

(Example 2)
The same procedure as in Example 1 was conducted except that the resin varnish was mixed as follows.
IXE-500 manufactured by Toa Gosei Co., Ltd., and 1.5 parts by weight of a bismuth inorganic ion exchanger (average particle size of about 1 μm) were used as the inorganic ion exchanger. Others were the same as in Example 1.

(Example 3)
The same procedure as in Example 1 was conducted except that the resin varnish was mixed as follows.
The inorganic ion exchanger was 0.5 parts by weight with respect to 100 parts by weight of the resin component, and the others were the same as in Example 1.

Example 4
The same procedure as in Example 1 was conducted except that the resin varnish was mixed as follows.
The inorganic ion exchanger was 2.5 parts by weight with respect to 100 parts by weight of the resin component, and the others were the same as in Example 1.

(Example 5)
The same procedure as in Example 1 was conducted except that the resin varnish was mixed as follows.
IXE-600 manufactured by Toagosei Co., Ltd. and 1.5 parts by weight of an antimony-bismuth inorganic ion exchanger (average particle size of about 1 μm) were used as the inorganic ion exchanger. Others were the same as in Example 1.

(Example 6)
The same procedure as in Example 1 was conducted except that the resin varnish was mixed as follows.
IXE-700F manufactured by Toagosei Co., Ltd., and 1.0 part by weight of an aluminum-magnesium inorganic ion exchanger (average particle size of about 1 μm) were used as the inorganic ion exchanger. Others were the same as in Example 1.

(Example 7)
The same procedure as in Example 1 was conducted except that the resin varnish was mixed as follows.
An inorganic ion exchanger manufactured by Toa Gosei Co., Ltd., IXE-700F, an aluminum-magnesium inorganic ion exchanger pulverized to an average particle size of 0.03 μm was prepared, and 1.0 part by weight was used. Others were the same as in Example 1.

(Example 8)
The same procedure as in Example 1 was conducted except that the resin varnish was mixed as follows.
An inorganic ion exchanger manufactured by Toa Gosei Co., Ltd., IXE-700F, an aluminum-magnesium inorganic ion exchanger pulverized to an average particle size of 0.1 μm was prepared, and 1.0 part by weight was used. Others were the same as in Example 1.

(Comparative Example 1)
The procedure was the same as Example 1 except that no inorganic ion exchanger was used.

(Comparative Example 2)
After preparing and stirring the resin varnish, the same procedure as in Example 1 was performed except that the inorganic ion exchanger was removed.

  The following evaluation was performed about the laminated board obtained by the Example and the comparative example. The evaluation items are shown together with the evaluation method. The obtained results are shown in Table 1.

(1) Moisture-absorbing solder heat resistance A test piece was prepared by cutting 50 mm × 50 mm from a double-sided copper clad laminate having a thickness of 0.2 mm and performing half-side etching according to JIS C 6481. After being treated with a pressure cooker at 121 ° C. for 2 hours, the copper foil surface was floated down in a solder bath at 260 ° C., and the presence or absence of abnormal appearance after 120 seconds was examined.

(2) Water absorption The double-sided copper-clad laminate having a thickness of 0.2 mm was entirely etched, and a 50 mm × 50 mm test piece was cut out from the obtained laminate and measured according to JIS C 6481.

(3) Moisture absorption property A test piece was prepared by cutting out from a double-sided copper-clad laminate having a thickness of 0.2 mm to 50 mm × 50 mm and performing half-surface etching. It was processed with a 125 ° C pressure cooker, taken out every predetermined time, and examined for the presence or absence of abnormal appearance, thereby measuring the time until blistering occurred.

(4) Peel strength deterioration after moisture absorption A test piece was prepared by cutting a double-sided copper-clad laminate having a thickness of 0.2 mm into 50 mm × 50 mm and performing single-side etching. It processed with the 125 degreeC pressure cooker, the test piece was taken out for every predetermined time, peel strength was measured according to JISC6481, and the half life of peel strength was investigated.

(5) Precipitation characteristic of inorganic ion exchanger at the time of varnish preparation After the resin varnish was prepared, the stirring was stopped and the mixture was allowed to stand for 5 minutes, and the precipitation of the inorganic ion exchanger was visually confirmed. The symbols are as follows.
◎: No sedimentation is observed ○: Sedimentation is observed, but disperses easily by stirring again

  As apparent from Table 1, in Examples 1 to 8, the occurrence of blistering during moisture absorption was suppressed, the peel deterioration rate during moisture absorption was slow, and the moisture absorption characteristics were excellent. Moreover, since Examples 7-8 used the thing with a small average particle diameter as an inorganic ion exchanger, it was excellent also in the workability | operativity at the time of resin varnish preparation.

The resin composition, prepreg and laminate of the present invention have moisture resistance and also retain the heat resistance, low thermal expansion and dielectric properties of cyanate resin. Therefore, the multilayer printed wiring board obtained from the resin composition, prepreg and laminate of the present invention can provide an IC package substrate having excellent heat resistance, small warpage, and excellent moisture resistance, and contributes greatly to related industries. can do.

Claims (9)

A resin composition used for impregnating a base material to form a sheet-like prepreg, comprising a cyanate resin and / or a prepolymer thereof, and an ion exchanger. The resin composition according to claim 1, comprising a thermosetting resin different from the cyanate resin. The resin composition according to claim 2, wherein the thermosetting resin contains an epoxy resin and / or a phenol resin. Furthermore, the resin composition in any one of the Claims 1 thru | or 3 containing an inorganic filler. The resin composition according to claim 1, wherein the ion exchanger includes an inorganic ion exchanger. The resin composition according to claim 5, wherein the inorganic ion exchanger has an average particle size of 0.02 to 5 μm. 7. The resin composition according to claim 1, wherein the content of the ion exchanger is 0.5 to 3 parts by weight with respect to 100 parts by weight of the resin composition. A prepreg obtained by impregnating a base material with the resin composition according to claim 1. A laminate obtained by molding one or more prepregs according to claim 8.