JP3738536B2 - Method for manufacturing printed wiring board - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a double-sided and multilayer printed wiring board used in various electronic devices.
[0002]
[Prior art]
In recent years, various electronic devices have been in the trend of miniaturization, weight reduction, and multi-functionality, and printed wiring boards used for them have been required to have high density. The one disclosed in Japanese Patent Laid-Open No. 6-268345 is known.
[0003]
FIGS. 7A to 7I are manufacturing process diagrams showing the conventional method of manufacturing a printed wiring board in cross section. First, as shown in FIG. 7A, the prepreg 102 such as an aramid epoxy sheet is formed. A laminate 103 is formed by bonding a film material 101 such as a polyethylene terephthalate material on both sides.
[0004]
Next, as shown in FIG. 7B, through holes 104 are formed in the laminate 103 by laser processing or the like, and the conductive paste 105 is squeezed into the through holes 104 as shown in FIG. 7C. It is filled by the operation.
[0005]
Subsequently, after peeling the film material 101 as shown in FIG. 7D, a copper foil 106 as a conductive layer is bonded to both sides as shown in FIG. As shown, the via hole 107 is formed by heating and pressing.
[0006]
Furthermore, as shown in FIG. 7G, a predetermined wiring pattern 108 is formed by etching or the like on one or both sides of the copper foil 106 so that the both-side wiring pattern 108 is electrically connected through the via hole 107. A wiring substrate 109 is obtained.
[0007]
Next, as shown in FIG. 7 (h), the prepreg 102 in which the conductive paste 105 is filled in the through-hole 104 shown in FIG. After bonding and heating and pressing, a single-sided or double-sided copper foil 106 is formed on a predetermined outer layer wiring pattern 110 by etching or the like, thereby obtaining a multilayer printed wiring board 111 as shown in FIG. It was.
[0008]
[Problems to be solved by the invention]
Generally, various thicknesses are required for printed wiring boards depending on the application, but in the conventional configuration, the thickness is limited to the thickness of a prepreg such as an aramid epoxy sheet, and in order to increase the thickness, how many layers of aramid epoxy sheet are used. In addition, the aramid epoxy sheet has a problem that it is relatively expensive compared to a general glass epoxy base material because the aramid epoxy sheet has a small circulation amount.
[0009]
An object of the present invention is to provide a method of manufacturing a printed wiring board that can easily realize various plate thicknesses and can obtain a printed wiring board that can be densified at low cost.
[0010]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a through-hole after attaching a release film on at least one surface of a base material having a copper foil on both sides and constituting a printed wiring board. After the conductive paste is filled in the holes, the release film is peeled off, and then the conductive paste is cured by heating and pressurizing the base material filled with the conductive paste in the through holes. After electrically connecting the copper foil provided on both surfaces and the conductive paste, the copper foil provided on both surfaces of the substrate is formed in a predetermined wiring pattern.
[0011]
According to the present invention, it is possible to easily form a double-sided printed wiring board having various plate thicknesses that can be densified.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
In the invention according to claim 1 of the present invention, a through-hole is provided after a release film is attached to at least one surface of a base material having a copper foil on both sides and constituting a printed wiring board. After the conductive paste is filled in the through hole, the release film is peeled off, and then the conductive paste is cured by heating and pressurizing the base material filled with the conductive paste in the through hole. A method of manufacturing a printed wiring board in which a copper foil provided on both sides of a base material is electrically connected to a conductive paste and then a copper foil provided on both sides of a base material is formed into a predetermined wiring pattern. The double-sided printed wiring board having various plate thicknesses and capable of high density can be easily formed.
[0013]
Invention of Claim 2 provides a through-hole in the base material which has a copper foil on both surfaces, and comprises a printed wiring board, makes the mask which has a through-hole corresponding to this through-hole adhere to the said base material, The conductive paste is filled into the through holes of the base material through the through holes of the mask, and then the conductive paste is cured by heating and pressing the base material filled with the conductive paste into the through holes. A method for manufacturing a printed wiring board in which a copper foil provided on both surfaces of a base material and a conductive paste are electrically connected and then a copper foil provided on both surfaces of the base material is formed in a predetermined wiring pattern. The double-sided printed wiring board can be easily formed with high density and various plate thicknesses, which can be reliably filled with the conductive paste into the through-holes and used multiple times. It has the action.
[0014]
The invention described in claim 3 has a through hole corresponding to the through hole after forming a through hole and a predetermined wiring pattern on the surface of the base material constituting the printed wiring board having copper foil on both sides. The mask is brought into close contact with the base material, the conductive paste is filled into the through hole of the base material through the through hole of the mask, and then the base material with the conductive paste filled into the through hole is heated and pressurized. A method for producing a printed wiring board in which the conductive paste is cured by the above and the copper foil provided on both surfaces of the base material is electrically connected to the conductive paste. In addition to the action, the conductive paste has an effect that there is no influence such as etching.
[0015]
The invention according to claim 4 is the conductivity according to any one of claims 1 to 3, wherein the conductive material is filled in the through-holes of the base material that has the copper foil on both sides and constitutes the printed wiring board. This is a method of manufacturing a printed wiring board in which the amount of paste is larger than the volume of the through hole. Even if the filling rate of the conductive paste varies, the resistance value of the via hole of the printed wiring board can be stabilized. Has the effect of being able to.
[0016]
The invention according to claim 5 is the printed wiring according to the invention according to claim 2 or 3, wherein the hole diameter of the through hole of the mask in contact with the substrate is the same as or smaller than the hole diameter of the through hole of the substrate. This is a method for manufacturing a substrate, and even if there is variation in the stretch of the mask and the positioning of the mask and the base material, the mask does not protrude from the through hole of the base material within the through hole of the base material. Only has the effect that the conductive paste can be filled.
[0017]
The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the conductive paste is cured by heating and pressurizing the substrate filled with the conductive paste in the through holes. In this case, it is a method of manufacturing a printed wiring board in which an elastic heat-resistant film is placed on both sides of a base material, and the conductive paste is put into the through holes of the base material when heated and pressed. It has the effect | action that it can harden | cure in the state pressurized and reliably pressurized, and can stabilize the resistance value of the formed via hole.
[0018]
The invention according to claim 7 is the inner layer substrate in which the wiring patterns formed on both surfaces of the base material constituting the printed wiring board in the invention according to any one of claims 1 to 6 are connected by through holes or via holes. A prepreg made of an aramid epoxy sheet filled with a conductive paste in the through hole is arranged on both sides of the substrate or alternately when there are a plurality of inner layer substrates, and a conductive layer is arranged on the outermost layer of the prepreg. This is a printed wiring board manufacturing method in which the outermost conductive layer of the prepreg is formed into a predetermined wiring pattern after being laminated by heating and pressurizing, and various plate thicknesses can be increased in density. The multilayer printed wiring board can be easily formed.
[0020]
The invention according to claim 8 uses the printed wiring board manufactured by the method for manufacturing a printed wiring board according to any one of claims 1 to 6 as an inner layer board, on both sides of the inner layer board, or an inner layer board. When there are a plurality of sheets, alternately arrange prepregs, and arrange the conductive layers on the outermost layer of this prepreg and laminate them by heating and pressurization, then form through holes, and copper plating on these through holes This is a method of manufacturing a printed wiring board in which a through hole is formed by the above method, and a conductive layer on the surface is formed in a predetermined wiring pattern. It has the effect | action that it can form in.
[0021]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is a manufacturing process diagram showing the manufacturing method of a double-sided printed wiring board according to the first embodiment of the present invention in a cross-section. First, in FIG. 1 (a), 1 is glass epoxy, polyamide or paper phenol. Is a base material that constitutes a printed wiring board composed of, for example, copper foil 2 is pasted on both sides, and the base material 1 having this copper foil 2 is generally commercially available as a copper-clad laminate, and has various board thicknesses. Are available.
[0022]
Next, as shown in FIG. 1 (b), a release film 3 such as a polyester film coated with an adhesive (not shown) is attached to both sides of the copper foil 2, and shown in FIG. 1 (c). Thus, the through-hole 4 is provided by a hole manufacturing means by drilling or laser processing.
[0023]
Next, as shown in FIG. 1D, after filling the through holes 4 with the conductive paste 5 made of metal powder, epoxy resin, hardener and the like by a filling means such as a squeegee operation, FIG. The release film 3 is peeled and separated as shown in FIG.
[0024]
At this time, the filling condition of the thickness of the releasable film 3 and the amount of the conductive paste 5 is determined so that the amount of the conductive paste 5 becomes larger than the volume of the through hole 4.
[0025]
Further, as shown in FIG. 1 (f), with a heat-resistant film 6 having elasticity such as polyimide, polyphenylene sulfide or polyetheretherketone placed on both surfaces of the base material 1, by a heating press or the like, The conductive paste 5 is cured by heating and pressurizing at 160 to 200 ° C. for 20 to 60 kg / cm ² for 30 to 180 minutes, and the copper foil 2 and the conductive paste provided on both surfaces of the substrate 1. 5 is electrically connected.
[0026]
Thereafter, the heat resistant film 6 is removed, and the outermost layer copper foil 2 is formed on the predetermined wiring pattern 7 by etching or the like, whereby the wiring pattern 7 on both sides is formed by the via holes 8 as shown in FIG. An electrically connected double-sided printed wiring board 9 is formed.
[0027]
(Embodiment 2)
FIG. 2 is a manufacturing process diagram showing a manufacturing method of a double-sided printed wiring board according to the second embodiment of the present invention in a cross-sectional view. First, in FIG. The base material 2 is a copper foil, and a through hole 4 is provided in this by hole manufacturing means such as drilling or laser processing as shown in FIG.
[0028]
Next, as shown in FIG. 2 (c), a mask 11 made of a metal material or a resin material provided with a through hole 10 corresponding to the through hole 4 is brought into close contact with the base material 1, and FIG. As shown, the conductive paste 5 is filled into the through-hole 4 through the through-hole 10 of the mask 11 by filling means such as a squeegee operation.
[0029]
At this time, even if there is variation in the elongation of the mask 11 and the positioning of the mask 11 and the base material 1, the conductive paste 5 is not adhered to the base material 1 of the through hole 10 of the mask 11 other than the through hole 4. The diameter of the contact surface is set to be the same as or smaller than the diameter of the through hole 4 of the substrate 1.
[0030]
At this time, the filling condition of the thickness of the mask 11 and the amount of the conductive paste 5 is set so that the amount of the conductive paste 5 is larger than the volume of the through hole 4.
[0031]
Next, after removing the mask 11 as shown in FIG. 2 (e), as shown in FIG. 2 (f), elasticity such as polyimide, polyphenylene sulfide or polyether ether ketone is formed on the upper and lower surfaces of the substrate 1. The conductive paste 5 is cured by heating and pressurizing at 160 to 200 ° C. under conditions of 20 to 60 kg / cm ² for 30 to 180 minutes with a heat-resistant film 6 having a surface mounted thereon. At the same time, the copper foil 2 and the conductive paste 5 provided on both surfaces of the substrate 1 are electrically connected.
[0032]
Thereafter, the heat-resistant film 6 is removed, and the outermost copper foil 2 is formed on the predetermined wiring pattern 7 by etching or the like, so that the wiring pattern 7 on both sides is formed by the via holes 8 as shown in FIG. An electrically connected double-sided printed wiring board 9 is formed.
[0033]
(Embodiment 3)
FIG. 3 is a manufacturing process diagram showing the manufacturing method of the double-sided printed wiring board in the third embodiment of the present invention in a cross-sectional view. First, in FIG. The base material 2 is a copper foil, and the copper foil 2 on both sides is formed on the base material 1 by etching or the like as shown in FIG.
[0034]
Subsequently, as shown in FIG. 3C, a through hole 4 is provided by a hole manufacturing means such as a drill or laser processing. In this case, the wiring pattern 7 may be formed after the through hole 4 is provided.
[0035]
Next, as shown in FIG. 3 (d), a mask 11 made of a metal material or a resin material provided with a through hole 10 corresponding to the through hole 4 is brought into close contact with the base material 1, and FIG. As shown, the through-hole 4 is filled with the conductive paste 5 by a filling means such as a squeegee operation through the through-hole 10 of the mask 11.
[0036]
At this time, the base of the through-hole 10 of the mask 11 is prevented so that the conductive paste 5 does not adhere to other than the through-hole 4 even if the elongation of the mask 11 and the positioning of the mask 11 and the substrate 1 vary as described above. The hole diameter of the surface in contact with the material 1 is set to be the same as or smaller than the hole diameter of the through hole 4 of the substrate 1.
[0037]
At this time, the filling condition of the thickness of the mask 11 and the amount of the conductive paste 5 is set so that the amount of the conductive paste 5 is larger than the volume of the through hole 4.
[0038]
Next, after removing the mask 11 as shown in FIG. 3 (f), elasticity such as polyimide, polyphenylene sulfide or polyether ether ketone is applied to both surfaces of the substrate 1 as shown in FIG. 3 (g). By placing the heat resistant film 6 having, and heating and pressurizing at 160 to 200 ° C. under a condition of 20 to 60 kg / cm ² for 30 to 180 minutes by removing the heat resistant film 6 by, for example, As shown in FIG. 3 (h), a double-sided printed wiring board 9 in which the wiring patterns 7 on both sides are electrically connected by via holes 8 is formed.
[0039]
(Embodiment 4)
FIG. 4 is a manufacturing process diagram showing the manufacturing method of the multilayer printed wiring board according to the fourth embodiment of the present invention in a cross section. First, as shown in FIG. In general, a through-hole is formed in a base material having copper foil on both sides, which is commercially available as a copper-clad laminate, by means of drilling or laser processing or the like, and thereafter a through-hole 28 by copper plating and a wiring pattern 7 by etching or the like are formed. It is a general one formed, and various plate thicknesses can be manufactured.
[0040]
Next, as shown in FIG. 4B, the inner layer substrate 14 is formed by filling the through holes 28 of the double-sided printed wiring board 12 with a hole-filling resin 13 such as an epoxy resin.
[0041]
Next, as shown in FIG. 4C, both sides of the inner layer substrate 14 or when there are a plurality of inner layer substrates 14 as shown in FIG. A prepreg 16 made of an aramid epoxy sheet filled with 15 is disposed, and a copper foil 17 as a conductive layer is disposed on the outermost layer.
[0042]
Subsequently, the prepreg 16 and the conductive paste 15 are cured by heating and pressurizing at 160 to 200 ° C. under a condition of 20 to 60 kg / cm ² for 30 to 180 minutes, and the wiring pattern 7 and copper are heated. The foil 17 is electrically connected by the conductive paste 15.
[0043]
Thereafter, the outermost layer copper foil 17 is formed on the predetermined wiring pattern 18 by etching or the like, so that the outermost layer wiring pattern 18 and the inner layer substrate 14 or the like, as shown in FIGS. A multilayer printed wiring board 20 in which inner layer boards 14 are electrically connected by via holes 19 is formed.
[0044]
(Embodiment 5)
FIG. 5 is a manufacturing process diagram showing the manufacturing method of the multilayer printed wiring board according to the fifth embodiment of the present invention in a cross-sectional view. In FIG. 5, the inner substrate 21 is the same as in the first to third embodiments. A double-sided printed wiring board 9 of various thicknesses manufactured by a method for manufacturing a printed wiring board. First, as shown in FIG. 5 (a), both sides of the inner layer substrate 21 or as shown in FIG. 5 (c). When there are a plurality of inner layer substrates 21, prepregs 16 made of an aramid epoxy sheet having through holes filled with conductive paste 15 are arranged alternately with inner layer substrates 21, and copper foils 17 as conductive layers are respectively disposed on the outermost layers. Arrange.
[0045]
Subsequently, the prepreg 16 and the conductive paste 15 are cured by heating and pressing at 160 to 200 ° C. under a condition of 20 to 60 kg / cm ² for 30 to 180 minutes, and the wiring pattern 7 or the inner layer. The via hole 8 and the copper foil 17 of the substrate 21 are electrically connected by the conductive paste 15.
[0046]
After that, the outermost layer copper foil 17 is formed on the predetermined wiring pattern 18 by etching or the like, so that the outermost layer wiring pattern 18 and the inner layer substrate 21 or as shown in FIG. 5B and FIG. A multilayer printed wiring board 22 in which inner layer boards 21 are electrically connected to each other through via holes 19 is formed.
[0047]
(Embodiment 6)
FIG. 6 is a manufacturing process diagram showing the manufacturing method of the multilayer printed wiring board according to the sixth embodiment of the present invention in a cross-sectional view. In FIG. 6, the inner layer substrate 21 is according to the first to third embodiments. A double-sided printed wiring board 9 having various plate thicknesses manufactured by a method of manufacturing a printed wiring board. First, as shown in FIG. 6 (a), the upper and lower sides of the inner substrate 21 or as shown in FIG. 6 (e). When there are a plurality of inner layer substrates 21, prepregs 23 such as glass epoxy are alternately disposed with the inner layer substrate 21, and copper foils 17 as conductive layers are disposed on the outermost layers, respectively. The prepreg 23 is cured as shown in FIGS. 6 (b) and 6 (f) by heating and pressurizing for 30 to 180 minutes under the condition of 20 to 60 kg / cm ² at ˜200 ° C.
[0048]
Next, as shown in FIGS. 6 (c) and 6 (g), through holes 24 are respectively provided by drilling or laser processing, and copper plating is applied to the inner walls of these through holes 24 and the surface of the copper foil 17. After forming the through hole 25, the outermost layer copper foil 17 is formed on the predetermined wiring pattern 26 by etching or the like, whereby a multilayer printed wiring board as shown in FIGS. 6 (d) and 6 (h) 27 are formed.
[0049]
【The invention's effect】
As described above, according to the present invention, it is possible to easily form a double-sided printed wiring board having various plate thicknesses and capable of increasing the density.
[Brief description of the drawings]
FIG. 1 is a manufacturing process diagram showing a manufacturing method of a double-sided printed wiring board according to a first embodiment of the present invention in a cross-sectional view. FIG. 2 shows a manufacturing method of a double-sided printed wiring board according to the second embodiment. Manufacturing process diagram shown in cross section of the main part [FIG. 3] Manufacturing process diagram showing the manufacturing method of the double-sided printed wiring board in the third embodiment in cross section of the main part [FIG. 4] Multilayer printing in the fourth embodiment Manufacturing process diagram showing a manufacturing method of a wiring board in a cross section of the main part. FIG. 5 is a manufacturing process diagram showing a manufacturing method of the multilayer printed wiring board in the fifth embodiment in a cross section of the main part. Manufacturing process diagram showing a manufacturing method of a multilayer printed wiring board in an embodiment in a cross section of the main part. FIG. 7 is a manufacturing process diagram showing a manufacturing method of a conventional double-sided printed wiring board in a main part.
DESCRIPTION OF SYMBOLS 1 Base material 2 Copper foil 3 Release film 4 Through-hole 5 Conductive paste 6 Heat resistant film 7 Wiring pattern 8 Via hole 9 Double-sided printed wiring board 10 Through-hole 11 Mask 12 Double-sided printed wiring board 13 Hole filling resin 14 Inner layer board 15 Conductive paste 16 Prepreg 17 Copper foil 18 Wiring pattern 19 Via hole 20 Multilayer printed wiring board 21 Inner layer board 22 Multilayer printed wiring board 23 Prepreg 24 Through hole 25, 28 Through hole 26 Wiring pattern 27 Multilayer printed wiring board

Claims (8)

  After attaching a release film on at least one surface of the base material constituting the printed wiring board having copper foil on both sides, a through hole is provided, and after filling the conductive paste in the through hole, the above-mentioned Copper foil and conductive paste provided on both sides of the substrate while peeling the release film and subsequently curing the conductive paste by heating and pressurizing the substrate filled with the conductive paste in the through holes A method for manufacturing a printed wiring board in which copper foils provided on both surfaces of a base material are formed into a predetermined wiring pattern after the electrical connection is established.   A through-hole is provided in a base material constituting a printed wiring board having copper foil on both sides, and a mask having a through-hole corresponding to the through-hole is brought into close contact with the base material, and conductive is conducted through the through-hole of the mask. The conductive paste is filled into the through holes of the base material, and then the conductive paste is cured by heating and pressurizing the base material filled with the conductive paste into the through holes, and the copper provided on both sides of the base material A method for manufacturing a printed wiring board in which a copper foil provided on both surfaces of a base material is formed in a predetermined wiring pattern after electrically connecting the foil and the conductive paste.   After forming a predetermined wiring pattern on the surface and the through-holes on the surface of the base material constituting the printed wiring board having copper foil on both sides, the mask having a through-hole corresponding to the through-hole is adhered to the base material, The conductive paste is hardened by filling the through hole of the base material through the through hole of the mask, and then heating and pressurizing the base material filled with the conductive paste in the through hole. A method for manufacturing a printed wiring board, wherein a copper foil provided on both surfaces of a base material and a conductive paste are electrically connected.   The quantity of the electrically conductive paste with which it fills in the through-hole of the base material which has copper foil on both surfaces and comprises a printed wiring board was made larger than the volume of this through-hole. Manufacturing method of printed wiring board.   The method for manufacturing a printed wiring board according to claim 2 or 3, wherein the hole diameter of the through hole of the mask in contact with the base material is the same as or smaller than the hole diameter of the through hole of the base material.   Claims wherein, when the conductive paste is cured by heating and pressurizing the base material filled with the conductive paste in the through holes, an elastic heat-resistant film is placed on both sides of the base material. The manufacturing method of the printed wiring board as described in any one of 1-5. Conductive paste is placed on both sides of the inner layer board that is connected by through holes or via holes to the wiring pattern formed on both sides of the base material that constitutes the printed wiring board, or alternately when there are multiple inner layer boards. A prepreg composed of a filled aramid epoxy sheet is disposed, and a conductive layer is disposed on each outermost layer of the prepreg and laminated by heating and pressing, and then the outermost conductive layer of the prepreg is formed into a predetermined wiring pattern. The manufacturing method of the printed wiring board as described in any one of Claims 1-6 made to form .   A printed wiring board manufactured by the method for manufacturing a printed wiring board according to any one of claims 1 to 6 is used as an inner layer substrate, on both sides of the inner layer substrate, or alternately when there are a plurality of inner layer substrates, After arranging the prepreg and arranging the conductive layers on the outermost layer of the prepreg and laminating them by heating and pressing, through holes are formed, and through holes are formed in the through holes by copper plating. A method for manufacturing a printed wiring board, wherein a conductive layer is formed in a predetermined wiring pattern.

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