JP2011254026A - Method of producing composite and composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing a composite having highly reliable fine wiring of small arithmetic average roughness (Ra) and vias formed in a resin layer of the composite, and to provide the composite.SOLUTION: The method of producing a composite having a resin layer and a conductor layer includes (A) a step for preparing the resin layer on a substrate, (B) a step for forming a resist layer on the resin layer, (C) a step for forming a groove in a surface of the resin layer by irradiating the surface of the resin layer with a laser beam through the resist layer, (D) a step for forming a conductor on the surface of the resin layer, and (E) a step for peeling the resist layer.

Description

  The present invention relates to a method for producing a composite and a composite.

  In recent years, with the demand for higher functionality, lighter weight, smaller size, and thinner electronic devices, high-density integration and high-density mounting of electronic components are progressing. Circuit wiring of printed wiring boards used in these electronic devices tends to have a higher density, and a built-up multilayer wiring structure is employed.

  As a method of connecting circuit wiring layers through a resin layer, for example, there is a method of forming an interlayer connection via in the resin layer (see, for example, Patent Document 1). In order to form a via, a laser such as a carbon dioxide laser, a YAG laser, or an excimer laser is irradiated on the resin layer, and after opening, the circuit wiring layers are connected by filling with conductive resin or plating. In this case, due to the influence of the inorganic filler in the resin layer and the absorption of the laser wavelength of the resin, the unevenness of the resin surface inside the via increases, so there is a problem in the accuracy when forming the via. It was difficult to form.

  Further, as a method of forming a circuit wiring pattern, there is generally a method (subtractive method) of etching a copper foil. The circuit thickness formed by the subtractive method is characterized by the thickness of the copper foil to be used, and the accuracy of the circuit width depends on the reaction characteristics of the etching solution and the ability of the etching apparatus to be used. For this reason, the subtractive method is generally not suitable for increasing the density, except for some applications using ultrathin metal foils.

  On the other hand, there is a semi-additive method as a method generally applied to the manufacture of build-up substrates and multilayer wiring boards. In this method, the resin surface is desmeared to roughen the surface, an electroless copper plating layer using a palladium catalyst is formed on the surface, a photosensitive resist is formed on the copper plating layer, and exposure / development is performed. After patterning through a process such as the above, a circuit pattern is formed by electrolytic copper plating, and finally the resist is peeled off and the electroless copper plating layer is removed by quick etching to form a fine wiring ( For example, see Patent Document 2). When fine wiring is formed by this method, there are problems such as exposure / development accuracy of resist and abnormal plating deposition due to palladium catalyst residue between wiring, and the circuit width / inter-circuit width (L / S) is 10 μm / 10 μm or less. It is difficult to form fine wiring.

  In the subtractive method and the semi-additive method, convex wiring is formed on the surface of the resin layer. In a build-up board or a multilayer wiring board, a process of laminating a resin layer is included in the subsequent process, but depending on the resin composition, a problem of resin embedding occurs. In particular, in a fine wiring region having a circuit width / inter-circuit width (L / S) of 10 μm / 10 μm or less, it becomes difficult to ensure insulation reliability when the resin embedding property deteriorates.

  Also, grooves are formed in the resin layer by scribing or plasma, the resin surface is desmeared to roughen the surface, an electroless copper plating layer using a palladium catalyst is formed on the surface, and then a conductor is formed by electrolytic copper plating Finally, there is a method of forming a circuit by removing conductor plating other than the groove portion by etching (see, for example, Patent Documents 3 and 4). In this case, since the unevenness of the groove side wall surface of the resin layer is large, there is a problem in accuracy in forming the groove, and it is necessary to form fine wiring having a circuit width / inter-circuit width (L / S) of 10 μm / 10 μm or less. was difficult.

JP 2008-274210 A JP-A-8-64930 Japanese Patent Laid-Open No. 10-4253 JP 2006-41029 A

  The present invention provides a method for producing a composite and a composite having fine wiring and vias formed on a resin layer of the composite and having high reliability and small arithmetic average roughness (Ra).

Such an object is achieved by the present invention described in the following [1] to [8].
[1] A method for producing a composite comprising a resin layer and a conductor layer,
(A) preparing a resin layer on the substrate;
(B) forming a resist layer on the resin layer;
(C) forming a groove on the resin layer surface by irradiating a laser beam through the resist layer;
(D) forming a conductor circuit on the resin layer surface;
(E) peeling the resist layer;
The manufacturing method of the composite_body | complex characterized by including.
[2] The method for producing a composite according to [1], wherein the step (D) is a step of forming a conductor circuit by electroless plating.
[3] The composite according to [1] or [2], further comprising (F) a step of forming a conductor circuit by electrolytic plating after the step (D) or the step (E). Production method.
[4] The composite according to any one of [1] to [3], further including (G) a quick etching step after the step (D), the step (E) or the step (F). Manufacturing method.
[5] The method for producing a complex according to any one of [1] to [4], including a step of performing desmear treatment with plasma or a chemical solution between the step (C) and the step (D).
[6] The method for producing a complex according to any one of [1] to [5], wherein the laser beam is an excimer laser or a YAG laser.
[7] The method for producing a composite according to any one of [1] to [6], wherein the resist layer is formed by laminating a dry film on the resin layer by lamination and exposing.
[8] A composite produced by the production method according to any one of [1] to [7].

  According to the present invention, it is possible to obtain a composite having fine wiring and vias with high reliability and small arithmetic average roughness (Ra) formed in the resin layer of the composite.

It is the schematic diagram shown about the example of the method of manufacturing a fine wiring by forming a groove | channel and forming a conductor layer in the composite_body | complex containing the resin layer and conductor layer which concern on this invention. It is the schematic diagram shown about an example of the method of manufacturing a via | veer in the composite_body | complex containing the resin layer and conductor layer which concern on this invention.

  The manufacturing method of the composite of the present invention is a method of manufacturing a composite including a resin layer and a conductor layer, and includes (A) a step of preparing a resin layer on a substrate, and (B) a resist on the resin layer. Forming a layer; (C) forming a via and / or a groove in the resin layer surface by irradiating a laser beam through the resist layer; and (D) providing a conductor on the resin layer surface. And (E) a step of peeling the resist layer. As a result, after the step (D), a part of the conductor is removed with an etching solution, and the process and the processing time for forming the conductor layer only in the via of the resin layer and / or the groove portion on the surface of the resin layer are largely omitted. In addition, it is possible to obtain a composite having high density, high reliability, high frequency compatible fine wiring and vias formed in the resin layer of the composite. The production method and composite of the composite of the present invention will be described in detail below.

  First, the manufacturing method of the composite_body | complex of this invention is demonstrated using figures. 1 and 2 are schematic views showing an example of a method for producing a composite including a resin layer and a conductor layer according to the present invention. The method for producing a composite according to the present invention is a method for producing a composite including a resin layer 2 and a conductor layer 91. (A) A resin layer 2 is prepared on a core substrate 1, and (B) a resin layer 2 is prepared. A step of forming a resist layer 10 thereon, and a step (C) of forming a groove 60 on the surface of the resin layer 2 by irradiating the laser beam 3 through the resist layer 10 (FIGS. 1A and 1B). And / or a step of forming a via 61 in the resin layer 2 (FIGS. 2A and 2B), and a step of forming a conductor 90 on the surface of the resin layer 2 (FIG. 1C). , (D), FIG. 2 (c), (d)), and (E) a step of removing the resist layer 10 (FIG. 1 (e), FIG. 2 (e)).

In the step (A), examples of the resist layer 10 include a method of forming a resist layer 10 on the surface of the resin layer 2 by laminating a dry film and exposing, a method of applying a liquid resist to the resin layer 2 and exposing, and the like. By using these, since the absorption rate of the laser beam is good, the processability with the laser beam is effectively improved, and the peelability from the resin layer 2 can be improved.

  In the step (C), the laser beam 3 is preferably an excimer laser or a YAG laser. By using these lasers, it is possible to form fine vias and grooves with good accuracy and shape. Although not particularly limited, the laser wavelength of the excimer laser is more preferably 193 nm, 248 nm, and 308 nm, and particularly preferably 193 nm and 248 nm. Thereby, the precision and shape are good, and the effect | action which can form a fine via | veer and a groove | channel can be expressed effectively. The wavelength of the YAG laser is preferably 355 nm. At other wavelengths, the resin composition constituting the resin layer 2 or the resist layer 10 may not absorb the laser light 3 and a via or groove may not be formed. The laser beam 3 is applied to the resist layer 10 and the resin layer 2 through the mask 4.

  In the manufacturing method of the composite_body | complex of this invention, it is preferable to include the process of desmearing with a plasma or a chemical | medical solution between a process (C) and a process (D). As a result, when the via 61 or the groove 60 is formed by the laser light 3, it is possible to form a via with high electrical reliability except for the carbide remaining on the side wall surface of the via 61 or the groove 60.

  The plasma desmear is not particularly limited, and nitrogen plasma, oxygen plasma, argon plasma, tetrafluoromethane plasma, or a mixed gas plasma thereof can be used. Further, the plasma processing conditions are such that the arithmetic average roughness (Ra) of the surface of the resin layer 2 after the plasma process is 0.05 μm or more and 0.25 μm or less, and at the same time, the via 61 and the groove 60. It is preferable that the conditions are sufficient to completely remove the remaining carbide on the side wall surface. This makes it possible to form vias and grooves with high insulation reliability and excellent signal response. In a high frequency region exceeding 1 GHz, transmission loss due to the skin effect can be reduced, and further, defective plating with vias and grooves and interlayer connection failures can be reduced. Although not particularly limited, it is more preferable that the plasma conditions be such that the arithmetic average roughness (Ra) after the plasma step is 0.05 μm or more and 0.20 μm or less. It is particularly preferable that the conditions be 15 μm or less. Thereby, insulation reliability and signal responsiveness can be improved, transmission loss can be reduced, and an effect that can reduce plating defects and interlayer connection defects in vias and grooves can be effectively exhibited.

  Although it does not specifically limit, permanganate, dichromic acid, etc. can be used for the desmear by a chemical | medical solution. Further, the desmear treatment conditions are such that the arithmetic average roughness (Ra) of the surface of the resin layer 2 after the desmear process is 0.05 μm or more and 0.25 μm or less. It is preferable that the conditions are sufficient to completely remove the remaining carbide on the side wall surface. This makes it possible to form vias and grooves with high insulation reliability, excellent signal responsiveness, and excellent reduction in plating defects and interlayer connection defects in vias and grooves. In a high frequency region exceeding 1 GHz, transmission loss due to the skin effect can be reduced. Although not particularly limited, it is more preferable that the desmear condition is such that the arithmetic average roughness (Ra) after the desmear process is 0.05 μm or more and 0.20 μm or less. It is particularly preferable that the conditions be 15 μm or less. Thereby, insulation reliability and signal responsiveness can be improved, transmission loss can be reduced, and the effect of reducing plating defects and interlayer connection defects in vias and grooves can be effectively exhibited.

  If the desmear process with plasma or chemicals is insufficient and carbides remain on the side walls of the vias and grooves, the insulation reliability of the composite may be reduced. If the desmear process with plasma or chemical solution is excessive, the arithmetic average roughness (Ra) of the surface of the resin layer 2 in the vias and grooves that are in contact with the conductor layer 91 becomes rough. Signal responsiveness may deteriorate, plating defects in vias and grooves, and interlayer connection failures may occur.

  In the step (D) of the present invention, a conductor is formed on the surface of the resin layer 2 after the step of desmearing the resin layer 2 with plasma or a chemical solution. In order to form a conductor, there is a method of forming a plating layer by ion plating or a chemical solution. When using a chemical solution, the plating layer is formed at least by electroless plating.

In the step (D) of the present invention, as an example of a method for forming a conductor on the surface of the resin layer 2, the electroless plating layer 7 is formed on the surface of the resin layer 2 by electroless plating.

  The type of metal of the electroless plating layer 7 is not particularly limited, but copper, nickel and the like are preferable. With these metals, the adhesion between the resin layer 2 and the electroless plating layer 7 is good. The thickness of the electroless plating layer 7 is not particularly limited, but is preferably about 0.1 to 5 μm. Furthermore, the adhesion between the resin layer 2 and the electroless plating layer 7 can be improved by performing a heat treatment at 150 ° C. to 200 ° C. for 10 minutes to 120 minutes after the electroless plating.

  In the step (E), the resist layer 10 is peeled off. As a result, the conductor can be selectively left only in the via 61 and the groove 60, and the use of excess etching solution and work efficiency can be greatly improved. When plating is performed without arranging the resist layer 10, a conductor is also formed on the surface of the resin layer 2 other than the via 61 and the groove 60, so that the surface of the resin layer 2 other than the via 61 and the groove 60 is exposed. For this reason, excessive etching is required.

  In the manufacturing method of the composite_body | complex of this invention, it is preferable to include the process (F) which forms the electroplating layer 80 further by electrolytic plating after a process (D) or a process (E). In this step, the via 61 and the groove 60 formed by the laser beam 3 can be filled with the electrolytic plating layer 80. In the step (F), the electrolytic plating layer 80 is formed on the electroless plating layer 7, and the conductor 90 composed of the electroless plating layer 70 and the electrolytic plating layer 80 is formed.

For the electrolytic plating, copper sulfate electrolytic plating can be used. Moreover, although not specifically limited, it is preferable that additives, such as a leveler agent, a polymer, and a brightener agent, are contained in a plating solution. Accordingly, plating is preferentially deposited on the via 61 and the via 60 formed in the resin layer 2 and is filled with the electrolytic plating layer 80. The thickness of the electrolytic plating layer is not particularly limited, but is preferably about 5 to 25 μm from the surface of the resin layer 2. As a result, the conductor layers can be connected via the vias 61, and fine wiring can be formed in the grooves 60.

  It is preferable that the manufacturing method of this invention includes the process (G) which performs quick etching after a process (D), a process (E), or a process (F). Thereby, a part of a small amount of the conductor 90 formed by the plating solution soaked into the interface between the resin layer 2 and the resist layer 10 can be removed, so that fine wiring and vias for high density, high reliability, and high frequency can be used. Can be formed. Usually, in the etching process, a chemical solution having a high etching rate is used, so that the etching processing time can be shortened. On the other hand, it is difficult to produce a fine circuit or to perform uniform and flat etching. Since a slow chemical solution is used, fine circuit fabrication and uniform and flat etching are facilitated. The conductor layer 91 formed by the electroless plating layer 71 and the electrolytic plating layer 81 is formed by the step (G).

  In the production method of the present invention, the step (H) of forming another resin layer on the resin layer 2 and the conductor layer 91 after the step (D), the step (E), the step (F) or the step (G). Can be included. In this case, it is preferable to roughen the surface of the conductor layer 91 by CZ treatment or blackening treatment. Thereby, the adhesive strength between the conductor layer 91 and another resin layer is increased, and the heat resistance is improved.

  By forming another resin layer on the resin layer 2 and the conductor layer 91, each conductor layer serving as the wiring of the composite is covered with the resin layer, and insulation between the vias is ensured. Although not particularly limited, examples of a method for forming another resin layer on the resin layer 2 and the conductor layer 91 include a method using a vacuum pressure laminator device, a flat plate press device, and the like.

  Thus, by repeating steps (A), (B), (C), (D), (E), (F), (G), (H), electrical reliability, signal responsiveness, vias and grooves It is possible to produce a multilayer composite having excellent plating properties and interlayer connectivity.

  Next, the composite of the present invention will be described. The composite of the present invention includes a resin layer and a conductor layer. Examples of the composite include a resin layer and a conductor layer formed on the wafer surface, a resin layer and a conductor layer formed on a metal substrate, and a resin layer (for example, a build-up layer) and a conductor layer formed on a printed wiring board. Etc.

Vias are formed in the resin layer of the composite of the present invention. The diameter of the via is preferably 1 μm or more and 25 μm. Thereby, it is possible to increase the density of the composite, increase the mounting, and make the fine wiring. Further, although not particularly limited, the diameter of the via is preferably 20 μm or less, more preferably 18 μm or less, and particularly preferably 15 μm or less. Thereby, the effect | action of high density, high mounting, and fine wiring can be expressed effectively.

If the diameter of the via is less than the above lower limit value, a location where a via cannot be formed in the resin layer with a laser beam or a connection failure may occur, or the circulation of the plating solution may deteriorate and the formation of a conductor by plating may not be possible. There is a possibility that the circuit wiring layers cannot be connected. Further, in a solder heat test, a thermal cycle test, etc., there is a possibility that peeling occurs at the interface between the via conductor and the resin. Also, if the upper limit is exceeded, the via shape when the via is formed with laser light becomes distorted (decrease in roundness), cracks may occur in the resin, and the heat is excessively applied to the resin. Insulation reliability may be reduced. In addition, it is difficult to increase the density of the composite, increase the mounting, and make fine wiring.

  In the composite of the present invention, it is preferable that at least the arithmetic average roughness (Ra) of the resin surface inside the via is 0.05 μm or more and 0.25 μm or less. Thereby, the unevenness of the resin surface of the via is reduced, and transmission loss due to the skin effect can be reduced in a high frequency region exceeding 1 GHz, and plating defects and interlayer connection failures in the via can be reduced. Although not particularly limited, the arithmetic average roughness (Ra) is more preferably 0.05 μm or more and 0.2 μm or less, and particularly preferably 0.05 μm or more and 0.15 μm or less. As a result, it is possible to effectively exhibit the effects of reducing transmission loss in the high frequency region and reducing plating defects and interlayer connection defects in vias.

  If the arithmetic average roughness (Ra) of the resin surface inside the via is less than the above lower limit value, peeling may occur at the interface between the via conductor and the resin in a solder heat resistance test, a thermal cycle test, etc. If the value is exceeded, high-speed signal transmission may be hindered, electrical reliability may be impaired, and plating defects in the vias or interlayer connection failures may occur.

  It is preferable that the maximum width of the conductor layer in the groove portion forming the fine wiring of the composite of the present invention is 1 μm or more and 10 μm or less. This makes it possible to increase the density and mount of the composite. Although not particularly limited, the maximum width of the conductor layer in the groove portion is more preferably 8 μm or less, further preferably 6 μm or less, and particularly preferably 4 μm or less. As a result, the effects of higher density and higher mounting can be effectively expressed.

  If the maximum width of the conductor layer in the groove portion is less than the above lower limit value, there may be a place where the groove cannot be formed in the resin layer with laser light, or the conductor layer may not be formed by plating, and the conductor layer is disconnected. There is a risk. Moreover, there is a possibility that the conductor layer may be peeled off in a solder heat test, a cooling / heating cycle test, or the like. Moreover, when it exceeds the said upper limit, since it takes time to form a groove | channel with a laser beam, workability | operativity will fall. In addition, it is difficult to increase the density of the composite, increase the mounting, and make fine wiring.

  The composite of the present invention preferably has an arithmetic average roughness (Ra) of at least the surface of the resin layer in the groove in contact with the conductor layer of 0.05 μm or more and 0.25 μm or less. Thereby, the surface unevenness | corrugation of a conductor layer becomes small and can reduce the transmission loss by the skin effect in the high frequency area | region exceeding 1 GHz, the poor plating with a groove | channel inside, and the poor connection of a conductor layer. Although not particularly limited, the arithmetic average roughness (Ra) is more preferably 0.05 μm or more and 0.2 μm or less, and particularly preferably 0.05 μm or more and 0.15 μm or less. As a result, the effect of reducing transmission loss in the high frequency region, reducing plating defects inside the groove, and poor connection of the conductor layer can be effectively expressed.

  If the arithmetic average roughness (Ra) of the resin layer surface inside the groove in contact with the conductor layer is less than the lower limit, the conductor layer may be peeled off in the solder heat resistance test, the cooling cycle test, etc. Exceeding this may hinder high-speed signal transmission, may impair electrical reliability, and may cause defective plating inside the groove and poor connection of the conductor layer.

  The arithmetic average roughness (Ra) is defined by JIS B0601. The arithmetic mean roughness (Ra) of the groove surface formed in the resin layer can be measured according to JIS B0651, and for example, it can be measured using WYKO NT1100 manufactured by Veeco.

Next, the resin composition used for the resin layer will be described. It is preferable that the resin composition which comprises a resin layer is comprised with the resin composition containing a thermosetting resin. Thereby, the heat resistance of the resin layer can be improved.

Examples of thermosetting resins include novolak type phenolic resins such as phenol novolak resin, cresol novolak resin, bisphenol A novolak resin, unmodified resol phenol resin, oil-modified resol phenol resin modified with tung oil, linseed oil, walnut oil, and the like. Phenol resin such as resol type phenol resin, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, bisphenol Z type epoxy resin, bisphenol P type epoxy resin, bisphenol M type epoxy resin Bisphenol epoxy resin, phenol novolac epoxy resin, cresol novolac epoxy resin novolac epoxy resin, biphenyl epoxy resin, bif Nylaralkyl type epoxy resin, aryl alkylene type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type epoxy resin, adamantane type epoxy resin, fluorene type epoxy resin, etc. Resin having triazine ring such as epoxy resin, urea (urea) resin, melamine resin, unsaturated polyester resin, bismaleimide resin, polyimide resin, polyamideimide resin, polyurethane resin, diallyl phthalate resin, silicone resin, benzoxazine ring Examples thereof include resins, triazine resins, benzocyclobutene resins, and cyanate resins. Among these, one or more resins selected from epoxy resins, phenol resins, cyanate resins, and benzocyclobutene resins are preferable, and cyanate resins are particularly preferable. Thereby, the thermal expansion coefficient of the resin layer can be reduced. Furthermore, the resin layer is excellent in electrical characteristics (low dielectric constant, low dielectric loss tangent), mechanical strength, laser workability, particularly excimer laser and YAG laser workability.

  Specific examples of the cyanate resin include novolak type cyanate resin, bisphenol A type cyanate resin, bisphenol E type cyanate resin, tetramethylbisphenol F type cyanate resin and the like, bisphenol type cyanate resins, naphthol aralkyl type cyanate resins, and biphenyl aralkyl type cyanate. Examples thereof include resins. Among these, novolac type cyanate resin is preferable. The novolac-type cyanate resin can reduce the thermal expansion coefficient of the resin layer, and is excellent in mechanical and mechanical strength and electrical characteristics (low dielectric constant, low dielectric loss tangent) of the resin layer. Naphthol aralkyl-type cyanate resins and biphenyl aralkyl-type cyanate resins can also be preferably used because they are excellent in low linear expansion, low water absorption, and mechanical strength.

  The weight average molecular weight of the cyanate resin is not particularly limited, but a weight average molecular weight of 500 to 4,500 is preferable, and 600 to 3,000 is particularly preferable. When the weight average molecular weight is less than the lower limit, the mechanical strength of the cured product constituting the resin layer may be reduced. Further, when the resin layer is produced, tackiness may occur and transfer of the resin may occur. There is. In addition, when the weight average molecular weight exceeds the above-described actual value, the curing reaction is accelerated, and when a substrate (particularly, a circuit substrate) is formed, molding defects may occur or the interlayer peel strength may be reduced. In addition, weight average molecular weights, such as cyanate resin, can be measured by GPC (gel permeation chromatography, standard substance: polystyrene conversion), for example.

  Further, although not particularly limited, cyanate resins including derivatives thereof can be used alone, or two or more having different weight average molecular weights can be used in combination, or one or two or more thereof. A prepolymer can also be used in combination.

  Although content of the said thermosetting resin is not specifically limited, 5 to 50 weight% of the whole resin composition is preferable, and 10 to 40 weight% is especially preferable. If the content is less than the lower limit, it may be difficult to form the resin layer, and if the content exceeds the upper limit, the strength of the resin layer may be reduced.

  When a cyanate resin (especially a novolac-type cyanate resin) is used as the thermosetting resin, it is preferable to use an epoxy resin (substantially free of halogen atoms) in combination.

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, bisphenol Z type epoxy resin, bisphenol P type epoxy resin, and bisphenol M type epoxy resin. Bisphenol type epoxy resin, phenol novolac type epoxy resin, novolac type epoxy resin such as cresol novolac epoxy resin, biphenyl type epoxy resin, xylylene type epoxy resin, arylalkylene type epoxy resin such as biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin, Naphthol aralkyl epoxy resin, anthracene epoxy resin, phenoxy epoxy resin, dicyclopentadiene epoxy resin, nor Runen type epoxy resins, adamantane type epoxy resins and fluorene type epoxy resins and the like. As the epoxy resin, one of these can be used alone, or two or more having different weight average molecular weights are used in combination, or one or two or more thereof and a prepolymer thereof are used in combination. You can also.

  Among these epoxy resins, aryl alkylene type epoxy resins are particularly preferable. Thereby, moisture absorption solder heat resistance and a flame retardance can be improved. The aryl alkylene type epoxy resin refers to an epoxy resin having one or more aryl alkylene groups in a repeating unit. For example, a xylylene type epoxy resin, a biphenyl dimethylene type epoxy resin, etc. are mentioned. Among these, a biphenyl dimethylene type epoxy resin is preferable. A naphthol aralkyl epoxy resin can also be preferably used because of its low linear expansion, low water absorption, and excellent mechanical strength.

  Although content of an epoxy resin is not specifically limited, 1 to 55 weight% of the whole resin composition is preferable, and 5 to 40 weight% is especially preferable. If the content is less than the lower limit, the reactivity of the cyanate resin may decrease, or the moisture resistance of the resulting product may decrease. If the content exceeds the upper limit, the low thermal expansion and heat resistance will decrease. There is a case.

  The weight average molecular weight of the epoxy resin is not particularly limited, but a weight average molecular weight of 500 to 20,000 is preferable, and 800 to 15,000 is particularly preferable. If the weight average molecular weight is less than the lower limit, tackiness may occur on the surface of the resin layer, and if it exceeds the upper limit, solder heat resistance may be reduced. By setting the weight average molecular weight within the above range, it is possible to achieve an excellent balance of these characteristics. The weight average molecular weight of an epoxy resin can be measured by GPC, for example.

  The resin composition which comprises the resin layer of the composite_body | complex of this invention can contain an inorganic filler. The average particle size of the inorganic filler that can be included in the resin composition constituting the resin layer is preferably 0.05 μm or more and 0.5 μm or less. Thereby, it is possible to form a fine wiring with high insulation reliability and excellent signal response. Further, although not particularly limited, the average particle size of the inorganic filler is more preferably 0.05 μm or more and 0.45 μm or less, and particularly preferably 0.05 μm or more and 0.40 μm or less. Thereby, the effect | action which improves insulation reliability, signal responsiveness, the plating property in a via | veer and a groove | channel, and interlayer connection reliability can be expressed effectively.

  The average particle diameter of the inorganic filler can be measured, for example, by a laser diffraction scattering method. The inorganic filler is dispersed in water by ultrasonic waves, and the particle size distribution of the inorganic filler is created on a volume basis by a laser diffraction type particle size distribution measuring device (manufactured by HORIBA, LA-500). It can be measured by doing. Specifically, the average particle diameter of the inorganic filler is defined by D50.

  The maximum particle size of the inorganic filler that can be included in the resin composition constituting the resin layer is preferably 2.0 μm or less. Thereby, it is possible to form a fine wiring with high insulation reliability and excellent signal response. Although not particularly limited, the maximum particle size of the inorganic filler is more preferably 1.8 μm or less, and particularly preferably 1.5 μm or less. Thereby, the effect | action which improves insulation reliability, signal responsiveness, the plating property in a via | veer and a groove | channel, and interlayer connection reliability can be expressed effectively.

  When the average particle size of the inorganic filler that can be included in the resin composition constituting the resin layer exceeds the above upper limit value, or when the maximum particle size of the inorganic filler exceeds the upper limit value, the inorganic filler becomes a laser. There is a risk that the processing may be hindered and there may be places where grooves cannot be formed in the resin layer, the via shape may become distorted, or cracks may occur in the resin, and the insulation reliability and plating performance may be reduced due to the drop of coarse filler. There is. Furthermore, since the time for forming vias and grooves with laser light becomes longer, workability may be reduced. Moreover, the surface unevenness | corrugation of the conductor layer after plating becomes large with the inorganic filler which remained on the groove | channel side wall surface after laser processing. As a result, the accuracy of the wiring and via shape deteriorates, and the insulation reliability may be impaired in a high-density printed wiring board. Furthermore, in a high frequency region exceeding 1 GHz, signal responsiveness may be impaired due to the skin effect.

  When the average particle size of the inorganic filler that can be included in the resin composition constituting the resin layer is less than the above lower limit, the physical properties of the thermal expansion coefficient and elastic modulus of the resin composition are lowered, and the semiconductor element mounting There is a possibility that the mounting reliability at the time may be harmed, and the resin film is formed by a decrease in the dispersibility of the inorganic filler in the resin composition, the occurrence of aggregation, or a decrease in the flexibility of the resin composition in the B-stage state. May become difficult.

  The inorganic filler that can be included in the resin composition constituting the resin layer is not particularly limited. For example, silicates such as talc, fired clay, unfired clay, mica, glass, titanium oxide, alumina, Oxides such as silica and fused silica, carbonates such as calcium carbonate, magnesium carbonate and hydrotalcite, hydroxides such as aluminum hydroxide, magnesium hydroxide, boehmite and calcium hydroxide, barium sulfate, calcium sulfate and calcium sulfite Sulfates or sulfites such as zinc borate, barium metaborate, borate such as aluminum borate, calcium borate, sodium borate, nitrides such as aluminum nitride, boron nitride, silicon nitride, carbon nitride, titanium Examples thereof include titanates such as strontium acid and barium titanate. As the inorganic filler, one of these can be used alone, or two or more can be used in combination. Among these, silica is preferable and fused silica is more preferable in terms of excellent low thermal expansion, flame retardancy, and elastic modulus. Among these, the shape is preferably spherical silica.

In addition, the resin composition constituting the resin layer includes, as necessary, a film-forming resin, a curing accelerator, a coupling agent, a pigment, a dye, an antifoaming agent, a leveling agent, an ultraviolet absorber, a foaming agent, an oxidation agent. You may add additives other than the said components, such as an inhibitor, a flame retardant, and an ion-trapping agent.

  Next, a method for forming a resin layer on the composite of the present invention will be described. Although not particularly limited, a method of forming a resin layer on a printed wiring board will be described as an example. The method for forming the resin layer on the printed wiring board is not particularly limited. For example, a resin varnish is prepared by dissolving and dispersing the resin composition constituting the resin layer in a solvent or the like, and using various coater devices A method of drying a varnish after applying it to a carrier film, etc., and a method of obtaining a resin sheet with a carrier film by spraying a resin varnish onto a carrier film using a spray device and then drying it. Is mentioned. Among these, it is preferable to apply a resin varnish to a carrier film or the like using various coater apparatuses such as a gravure coater, a comma coater, and a die coater and then dry the resin varnish. Thereby, the resin sheet with a carrier film which has no void and has a uniform thickness of the resin layer can be efficiently produced.

  A resin layer can be formed by thermocompression-bonding the obtained resin sheet with a carrier film to a substrate using, for example, a laminator or a vacuum press machine. The resin layer can also be formed by coating the substrate with a resin varnish directly. In addition to the printed wiring board, for example, when forming a resin layer on a wafer, the resin layer is formed by a method of producing a resin sheet with a carrier film and thermocompression bonding as described above, or a method of coating a resin varnish. Can be formed.

  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 acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, tetrahydrofuran, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, ethylene glycol, cellosolve and carbitol. Although it does not specifically limit as solid content in the said resin varnish, 30 to 80 weight% is preferable and especially 40 to 70 weight% is preferable.

  Next, the via shape of the composite of the present invention will be described. The cross-sectional shape of the via is preferably substantially trapezoidal. This makes it possible to form vias with excellent signal response, connection reliability, and plating performance.

  Moreover, it is preferable that the cross-sectional shape of the conductor layer which consists of the groove part of the composite_body | complex of this invention is substantially trapezoid shape, bowl shape, or a triangle. As a result, it is possible to form fine wiring with excellent signal response.

  Hereinafter, although an example and a comparative example explain the present invention, the present invention is not limited to this.

<Example 1>
20 parts by weight of novolak-type cyanate resin (Lonza Japan Co., Ltd., Primaset PT-30, weight average molecular weight of about 700), 35 weights of methoxynaphthalenedi-methylene type epoxy resin (Dainippon Ink and Chemicals, EXA-7320) Parts, 5 parts by weight of a phenoxy resin (manufactured by Japan Epoxy Resin Co., Ltd., jER4275), 0.2 parts by weight of an imidazole compound (manufactured by Shikoku Chemicals Co., Ltd., Curazole 1B2PZ (1-benzyl-2-phenylimidazole)) are dissolved in methyl ethyl ketone, Dispersed. An inorganic filler / spherical fused silica (SFP-20M, manufactured by Denki Kagaku Kogyo Co., Ltd.) is filtered and separated using a laminated cartridge filter (manufactured by Sumitomo 3M Co., Ltd.), and particles having a maximum particle size of 2.0 μm are separated by filtration. 40 parts by weight of an inorganic filler / spherical fused silica having a diameter of 0.4 μm was added. A resin having a solid content of 50% by weight by adding 0.2 parts by weight of a coupling agent / epoxysilane coupling agent (GE-Toshiba Silicone Co., Ltd., A-187) and stirring for 10 minutes using a high-speed stirring device. A varnish was prepared.

  The resin varnish obtained above was applied to one side of a 38 μm thick polyethylene terephthalate film (Mitsubishi Resin Co., Ltd.) using a comma coater so that the thickness of the resin film after drying would be 20 μm. And this was dried for 10 minutes with a 160 degreeC drying apparatus, and the resin sheet with a carrier film was produced.

  This resin sheet with a carrier film is superimposed on the front and back of a core substrate with a double-sided conductor layer, and this is vacuum-heated and pressure-molded at a temperature of 100 ° C. and a pressure of 1 MPa using a vacuum-pressure laminator, and then dried with hot air The substrate was heat-cured at 180 ° C. for 45 minutes with an apparatus to obtain a substrate with a resin layer.

In addition, the following were used as a core substrate with a double-sided conductor layer.
・ Resin layer: Halogen free, core substrate thickness 0.4mm
Conductor layer: copper foil thickness 18 μm, circuit width / inter-circuit width (L / S) = 120/180 μm, clearance holes 1 mmφ, 3 mmφ, slit 2 mm

  After peeling off the carrier film, a dry film (UFG-255 manufactured by Asahi Kasei) is laminated on the surface of the resin layer using a roll laminator, and the dry film is exposed (parallel light exposure machine: EV-0800 manufactured by Ono Sokki, exposure condition: exposure amount) 140 mJ, hold time 15 minutes) to form a resist layer.

(1) Formation of vias Vias having a diameter of 25 μm were formed on the resin layer of the substrate with a resin layer at intervals of 0.1 mm using an excimer laser (ATLEX-300SI, manufactured by Beam Co., Ltd.) having a wavelength of 193 nm (ArF).
The processing conditions were set as follows.
Mask diameter: 200 μm
Frequency: 100Hz
Energy: 100mJ / cm ²
Number of shots: 90
(2) Formation of groove To form a groove to be a fine wiring, similarly, an excimer laser having a wavelength of 193 nm (ArF) (ATLEX-300SI, manufactured by Beam Co., Ltd.) is used. A groove having a length of 10 μm and a length of 50 μm was formed. By repeating this, a groove having a width of 10 μm and a minimum inter-groove width of 10 μm was formed and connected to the via.
The processing conditions were set as follows.
Mask: 100 μm × 500 μm
Frequency: 00Hz
Energy: 500mJ / cm ²
Number of shots: 80

  The substrate with the resin layer in which the via and the groove are formed is left with the resist layer, and is immersed in a swelling liquid at 60 ° C. (Swelling Dip Securigant P500, manufactured by Atotech Japan Co., Ltd.) for 10 minutes, and further permanganic acid at 80 ° C. After dipping in a potassium aqueous solution (Atotech Japan Co., Ltd., Concentrate Compact CP) for 20 minutes, it was neutralized and desmeared.

  Next, after the steps of degreasing, applying a catalyst, and activating, an electroless copper plating layer of about 0.2 μm was formed.

Next, electroless copper plating (Okuno Pharmaceutical Co., Ltd., Top Lucina α) was performed at 3 A / dm ^{2 using the} electroless copper plating layer as an electrode to form a conductor up to the height on the resin surface layer.

  Next, after stripping the resist layer (stripping solution: R-100, manufactured by Mitsubishi Gas Chemical Co., Ltd., stripping time: 240 seconds), the conductor existing on the resin surface layer at the boundary between the via and the groove is subjected to a quick etching treatment (Kashihara Densha Co., Ltd.) SAC process manufactured by Sangyo Co., Ltd., etching rate of about 0.7 μm / min, processing time of about 4 minutes) was performed, the shape of the conductor was adjusted, and insulation between the via and the fine wiring was ensured. Next, the insulating resin layer was completely cured at a temperature of 200 ° C. for 60 minutes.

  Finally, a solder resist (manufactured by Taiyo Ink Manufacturing Co., Ltd., PSR4000 / AUS703) was formed on the circuit surface to produce a four-layer printed wiring board.

<Example 2>
A four-layer printed wiring board was produced in the same manner as in Example 1 except that the mask diameter during via formation was 150 μm.

<Example 3>
A four-layer printed wiring board was produced in the same manner as in Example 1 except that the mask diameter during via formation was set to 100 μm.

<Example 4>
A four-layer printed wiring board was produced in the same manner as in Example 1 except that the mask diameter during via formation was 50 μm.

<Example 5>
A four-layer printed wiring board was produced in the same manner as in Example 1 except that an excimer laser having a wavelength of 248 nm (KrF) was used.

<Example 6>
A four-layer printed wiring board was produced in the same manner as in Example 1 except that a YAG laser having a wavelength of 355 nm (LU-2G121 / 2C, manufactured by Hitachi Via Mechanics Co., Ltd.) was used.

<Comparative Example 1>
An epoxy resin buildup material (manufactured by Ajinomoto Co., Inc., GX-13, maximum particle diameter of filler 2.5 μm) is superimposed on the front and back of the core substrate with a double-sided conductor layer, and this is used with a vacuum pressure laminator device Then, vacuum heating and pressing were performed at a temperature of 100 ° C. and a pressure of 1 MPa, and the carrier film was peeled off.

In addition, the following were used as a core substrate with a double-sided conductor layer.
・ Resin layer: Halogen free, core substrate thickness 0.4mm
Conductor layer: copper foil thickness 18 μm, circuit width / inter-circuit width (L / S) = 120/180 μm, clearance holes 1 mmφ, 3 mmφ, slit 2 mm

(1) Formation of vias Vias having a diameter of 25 μm were formed on the resin layer of the substrate with a resin layer at intervals of 0.1 mm using an excimer laser (ATLEX-300SI, manufactured by Beam Co., Ltd.) having a wavelength of 193 nm (ArF).
The processing conditions were set as follows.
Mask diameter: 200 μm
Frequency: 100Hz
Energy: 100mJ / cm ²
Number of shots: 90

(2) Formation of groove To form a groove to be a fine wiring, similarly, an excimer laser having a wavelength of 193 nm (ArF) (ATLEX-300SI, manufactured by Beam Co., Ltd.) is used. A groove having a length of 10 μm and a length of 50 μm was formed. By repeating this, a groove having a width of 10 μm and a minimum inter-groove width of 10 μm was formed and connected to the via.
The processing conditions were set as follows.
Mask: 100 μm × 500 μm
Frequency: 100Hz
Energy: 500mJ / cm ²
Number of shots: 80

  The substrate with a resin layer in which vias and grooves are formed is immersed in a swelling solution at 60 ° C. (Swelling Dip Securigant P500, manufactured by Atotech Japan Co., Ltd.) for 10 minutes, and further an aqueous potassium permanganate solution at 80 ° C. (Atotech Japan Co., Ltd.). Manufactured, manufactured by Concentrate Compact CP) for 20 minutes, neutralized and desmeared.

  Next, after the steps of degreasing, applying a catalyst, and activating, an electroless copper plating layer of about 0.2 μm was formed.

Next, electrolytic copper plating (Okuno Pharmaceutical Co., Ltd., Top Lucina α) is performed at 3 A / dm ² for 30 minutes using the electroless copper plating layer as an electrode, so that the thickness of the resin surface layer is about 30 μm. Formed.

  Next, the conductor existing in the resin surface layer with a thickness of about 30 μm is removed by an etching process (manufactured by Mitsubishi Gas Chemical Co., Ltd., CPE-750, an etching rate of about 4.5 μm / min, a processing time of about 7 minutes). Insulation between via and fine wiring was ensured. Next, the insulating resin layer was completely cured at a temperature of 200 ° C. for 60 minutes.

  Finally, a solder resist (manufactured by Taiyo Ink Manufacturing Co., Ltd., PSR4000 / AUS703) was formed on the circuit surface to produce a four-layer printed wiring board.

<Comparative example 2>
A four-layer printed wiring board was produced in the same manner as in Comparative Example 1 except that a YAG laser having a wavelength of 355 nm was used.

<Comparative Example 3>
Using the resin varnish produced in Example 1, a 4-layer printed wiring board was produced in the same manner as in Comparative Example 1. In addition, in order to compare with Example 1 instead of an etching process (Mitsubishi Gas Chemical Co., Ltd. make, CPE-750, an etching rate of about 4.5 micrometer / min, processing time about 7 minutes) in the work process of the comparative example 1. Then, a quick etching process (SAC process manufactured by Ebara Densan Co., Ltd., etching rate: about 0.7 μm / min, processing time: about 4 minutes) was performed.

The evaluation method is as follows. The results are shown in Tables 1 and 2.

1. Via Top Diameter The top surface of the via of the resin layer after desmear treatment and peeling of the resist layer was observed with a scanning electron microscope (SEM), and the top diameter of the via was measured.

2. Arithmetic average roughness (Ra) of resin surface in via
After cutting the via cross section of the four-layer printed wiring board vertically and removing the conductor layer by etching, the resin surface in the via was measured using WYKO NT1100 manufactured by Veeco in accordance with JIS B0651.

3. Resin surface roughness in the groove (Ra)
The cross section of the fine wiring of the four-layer printed wiring board was cut vertically, the conductor layer was removed by etching, and the resin surface in the groove was measured using WYKO NT1100 manufactured by Veeco in accordance with JIS B0651.

4). Maximum width of groove The cross section of the fine wiring of the four-layer printed wiring board was cut vertically, and the maximum width in the groove was measured with an optical microscope.

5). Cross-sectional shape of groove The cross-section of the fine wiring of the four-layer printed wiring board was cut vertically, and the shape in the groove was observed with an optical microscope.

6). Connection reliability test The insulation resistance value between vias was monitored while treating a 4-layer printed wiring board having a distance between via walls of 0.1 mm under conditions of 135 ° C., 85% RH, and applied voltage 50 V for 200 hours.
Each code is as follows.
○: 1.0 × 10 ⁹ Ω or more ×: Less than 1.0 × 10 ⁹ Ω

7). Plating property The cross section of the via of the four-layer printed wiring board was cut, and the cut surface was observed with a scanning electron microscope (SEM) to examine the plating property in the via. Each code is as follows.
○: Plating is filled in the via without any gap, and there is no practical problem.
X: Plating has some micro voids in the via, and there is a practical problem.

  As is apparent from Table 1, Examples 1 to 6 can simplify the work by omitting the conventional etching process and only the quick etching process, and the via diameter is 25 μm or less, and the maximum width of the groove of the fine wiring is Since it can be formed at 10 μm or less, a high-density composite can be produced, and since the average roughness (Ra) of the resin layer is 0.05 μm or more and 0.25 μm or less, signal response, high frequency response and A good via and fine wiring excellent in the insulation reliability and the effect of reducing defects in plating and interlayer connection in the via and fine wiring could be formed.

  According to the present invention, it is possible to obtain a composite having a via formed on the surface of the resin layer of the composite, having high adhesion, high reliability, high frequency response, vias and vias having fine plating in a fine wiring and excellent interlaminar connectivity. Therefore, in particular, it can be suitably used for, for example, a printed wiring board having fine wiring with a circuit width / inter-circuit width (L / S) of 10 μm / 10 μm or less.

DESCRIPTION OF SYMBOLS 1 Core substrate 10 Resist layer 2 Resin layer 3 Laser beam 4 Mask 5 Conductor layer 60 Groove 61 Via 7 Electroless plating layer 70 Electroless plating layer 71 Electroless plating layer 80 Electrolytic plating layer 81 Electrolytic plating layer 90 Conductor 91 Conductive layer

Claims (8)

A method for producing a composite comprising a resin layer and a conductor layer,
(A) preparing a resin layer on the substrate;
(B) forming a resist layer on the resin layer;
(C) forming a groove on the resin layer surface by irradiating a laser beam through the resist layer;
(D) forming a conductor circuit on the resin layer surface;
(E) peeling the resist layer;
The manufacturing method of the composite_body | complex characterized by including. The method for producing a composite according to claim 1, wherein the step (D) is a step of forming a conductor circuit by electroless plating.   The method for producing a composite according to claim 1 or 2, further comprising (F) a step of forming a conductor circuit by electrolytic plating after the step (D) or the step (E). The manufacturing method of the composite_body | complex in any one of Claim 1 thru | or 3 including the process of performing (G) quick etching further after the said process (D), the said process (E), or the said process (F).   The manufacturing method of the composite_body | complex in any one of Claim 1 thru | or 4 including the process of performing a desmear process with a plasma or a chemical | medical solution between the said process (C) and the said process (D).   6. The method for producing a composite according to claim 1, wherein the laser beam is an excimer laser or a YAG laser.   The method for producing a composite according to claim 1, wherein the resist layer is formed by laminating a dry film on the resin layer by lamination and exposing.   A composite produced by the production method according to claim 1.