JP2010016244A - Method of manufacturing wiring circuit board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a wiring circuit board, by which the defect of a wiring pattern can accurately be detected. <P>SOLUTION: In an inspection step, a light irradiation unit 55 irradiates the wiring circuit board 100 with inspection light, and a light-receiving unit 56 receives its reflected light. The defect of the wiring pattern 6 is detected based upon the light received by the light-receiving unit 56. As the inspection light, violet light, blue light, or verdure light is used which has maximum light intensity in a wavelength range of 400 to 500 nm. Further, a filler of 0.002 to 0.5 μm in average particle diameter is added to an insulating layer of the wiring circuit board 100. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a printed circuit board.

  The printed circuit board has a configuration in which a predetermined wiring pattern made of a metal material is formed on one surface of an insulating layer made of a resin material, for example. When the printed circuit board is manufactured, a defect in the wiring pattern is detected in the inspection process.

In the inspection process, for example, light is irradiated toward one surface of the insulating layer, and a defect in the wiring pattern is detected based on the reflected light.
JP 2003-68805 A

  However, in the case where a material having high light transmittance such as polyimide is used as the material of the insulating layer, the irradiated light may pass through the insulating layer. In that case, when a ground layer or the like made of metal is formed on the other surface of the insulating layer, the light transmitted through the insulating layer is reflected by the layer on the other surface side of the insulating layer. The reflected light may be erroneously recognized as reflected light by the wiring pattern. Thereby, the defect of the wiring pattern is not accurately detected.

  The objective of this invention is providing the manufacturing method of the printed circuit board which can detect the defect of a wiring pattern correctly.

  (1) A method for manufacturing a printed circuit board according to the present invention includes a step of forming a polyimide layer containing a filler having an average particle size of 0.002 μm or more and 0.5 μm or less, and a step of forming a wiring pattern on the polyimide layer. And a step of irradiating the polyimide layer with light having a maximum light intensity in a wavelength region of 400 nm to 500 nm by the light irradiating unit and detecting a reflection of the reflected light by the light receiving unit. It is provided.

  In this manufacturing method, a wiring pattern is formed on a polyimide layer containing a filler having an average particle size of 0.002 μm or more and 0.5 μm or less. In this case, when the polyimide layer contains a filler, irregularities are formed on the surface of the wiring pattern. Thereby, the slipperiness of the wiring pattern is improved, and the printed circuit board can be smoothly conveyed by the roll-to-roll method.

  After the wiring pattern is formed, the light irradiating unit irradiates the polyimide layer with light having the maximum light intensity in the wavelength region of 400 nm or more and 500 nm or less, and the reflected light is received by the light receiving unit. A defect in the wiring pattern is detected based on the received light.

  In this case, the use of light having the maximum light intensity in the wavelength region of 500 nm or less prevents the irradiated light from passing through the polyimide layer. Thereby, when another layer made of metal is formed on the lower surface of the polyimide layer, it is possible to prevent the reflected light from the layer from being erroneously recognized as the reflected light from the wiring pattern. Further, the use of light having the maximum light intensity in the wavelength region of 400 nm or more prevents the surface of the polyimide layer from being modified.

  Furthermore, since the average particle diameter of the filler contained in the polyimide layer is 0.002 μm or more and 0.5 μm or less, the irradiation light is prevented from being reflected by the filler in the polyimide layer. This prevents the reflected light from the filler from being erroneously recognized as reflected light from the wiring pattern.

  As a result, it is possible to accurately detect defects in the wiring pattern.

  (2) The filler may include at least one of silica, calcium phosphate, calcium hydrogen phosphate, and alumina. In this case, the slipperiness of the wiring pattern can be sufficiently improved while maintaining the flexibility and flexibility of the polyimide layer.

  (3) In the step of inspecting the defect of the wiring pattern, the light irradiation unit may irradiate the polyimide layer with light having the maximum light intensity in a wavelength region of 425 nm or more and 475 nm or less.

  In this case, it is possible to more sufficiently prevent the irradiation light from passing through the polyimide layer, and it is possible to detect a wiring pattern defect more accurately. Also. It is possible to more sufficiently prevent the surface of the polyimide layer from being modified.

  (4) In the step of inspecting the defect of the wiring pattern, a light receiving unit having higher sensitivity to light in a wavelength region of 400 nm or more and 500 nm or less than light sensitivity in a wavelength region of greater than 500 nm may be used.

  In this case, even if light having a wavelength of more than 500 nm passes through the polyimide layer and is reflected by another layer formed on the lower surface of the insulating layer, the light is not easily detected by the light receiving unit. Therefore, it is possible to efficiently detect a defect in the wiring pattern.

  According to the present invention, it is possible to smoothly convey a printed circuit board by the roll-to-roll method, and it is possible to prevent erroneous recognition of reflected light by the wiring pattern and to accurately detect a defect in the wiring pattern.

  Hereinafter, a method for manufacturing a printed circuit board according to an embodiment of the present invention will be described with reference to the drawings.

(1) Manufacturing Method FIGS. 1 and 2 are manufacturing process diagrams showing an outline of a method for manufacturing a printed circuit board according to the present embodiment.

  First, as shown in FIG. 1A, an insulating layer 1 is laminated on a ground layer 2 made of, for example, copper via an adhesive layer (not shown). As the insulating layer 1, a material in which particulate filler is added to polyimide is used. The insulating layer 1 is an example of a polyimide layer in the claims. Details of the insulating layer 1 will be described later.

  The thickness of the insulating layer 1 is, for example, not less than 1 μm and not more than 100 μm, and preferably not less than 3 μm and not more than 50 μm. The thickness of the ground layer 2 is, for example, 1 μm or more and 100 μm or less, and preferably 3 μm or more and 75 μm or less. The material of the ground layer 2 is not limited to copper, and other metal materials such as a copper alloy, gold, and aluminum may be used.

  Next, as shown in FIG. 1B, a conductive thin film 3 made of, for example, copper is formed on the insulating layer 1. Next, as shown in FIG. 1C, a photoresist 4 is formed on the conductive thin film 3. Then, as shown in FIG. 1D, the photoresist 4 is exposed in a predetermined pattern and then developed. Thereby, the photoresist 4 having a pattern opposite to the conductor pattern to be formed in the subsequent process is formed.

  Next, as shown in FIG. 2A, a conductor layer 5 made of copper, for example, is formed on the exposed conductive thin film 3 by electrolytic plating. Next, as shown in FIG. 2B, the photoresist 4 is removed by etching or peeling. Finally, as shown in FIG. 2C, the exposed portion of the conductive thin film 3 is removed by etching. Thereby, the wiring pattern 6 including the conductive thin film 3 and the conductor layer 5 is formed.

  The thickness of the wiring pattern 6 is, for example, 1 μm or more and 50 μm or less, and preferably 1 μm or more and 30 μm or less. The material of the wiring pattern 6 is not limited to copper, and other metal materials such as copper alloy, gold, and aluminum may be used. The materials of the conductive thin film 3 and the conductor layer 5 may be the same or different. Further, the material of the wiring pattern 2 and the material of the ground pattern 4 may be different.

  In this way, the printed circuit board 100 is completed. In this example, the wiring pattern 6 is formed using the semi-additive method. However, the present invention is not limited to this, and the wiring pattern 6 may be formed using another method such as a subtractive method.

(2) Insulating layer As described above, the insulating layer 1 is made of a material in which particulate filler is added to polyimide. In this case, irregularities are formed on the surface of the insulating layer 1. Thereby, irregularities are also formed on the surface of the wiring pattern 6 formed on the insulating layer 1.

  When the printed circuit board 100 is transported by the roll-to-roll method, if the surface of the wiring pattern 6 is uneven, the contact area between the transporting roller (hereinafter referred to as the transporting roller) and the wiring pattern 6 becomes small. . Therefore, the slipperiness of the wiring pattern 6 with respect to the transport roller is improved. As a result, the printed circuit board 100 can be transported smoothly.

  Hereinafter, the manufacturing method of the insulating layer 1 is demonstrated concretely.

(2-1) Manufacture of polyimide First, polyamic acid which is a precursor of polyimide is manufactured. The polyamic acid is usually prepared by dissolving at least one aromatic dianhydride and at least one diamine in an organic solvent so as to have a substantially equimolar amount, and controlling the obtained polyamic acid solution. And stirring under the above temperature conditions until the polymerization of the acid dianhydride and the diamine is completed.

  A polyamic acid solution obtained by another polymerization method may be used. Further, two or more kinds of polyamic acid solutions polymerized separately can be used in combination.

  The concentration of these polyamic acid solutions is appropriately adjusted according to the application and process. The concentration of the polyamic acid solution is, for example, in the range of 10 wt% to 40 wt%, and preferably in the range of 15 wt% to 35 wt%. In this case, an appropriate molecular weight and solution viscosity for imidization described later are ensured.

  In addition, the preparation method of a polyamic acid solution is not limited to this, You may prepare a solution-like polyamic acid composition by another method.

  In the production of the polyamic acid, examples of the aromatic dianhydride include pyromellitic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 3,3 ′, 4,4 ′. -Biphenyltetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride, 3,3', 4 4′-benzophenonetetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, bis (3 4-dicarboxyphenyl) propane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2,3 Dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) ethane dianhydride, oxydiphthalic dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, p-phenylenebis ( Trimellitic acid monoester acid anhydride), ethylene bis (trimellitic acid monoester acid anhydride), bisphenol A bis (trimellitic acid monoester acid anhydride), and the like can be suitably used.

  These aromatic acid dianhydrides may be used alone, or two or more of them may be mixed at an arbitrary ratio and used as a mixture.

  In particular, as the aromatic dianhydride, pyromellitic dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride It is preferable to use an anhydride or p-phenylenebis (trimellitic acid monoester acid anhydride). These compounds may be used alone, or two or more kinds may be mixed at an arbitrary ratio and used as a mixture.

  In the production of the polyamic acid, examples of the diamine include 4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenylmethane, benzidine, 3,3′-dichlorobenzidine, 4,4′-diaminodiphenyl sulfide. 3,3′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 4,4′diaminodiphenylether, 3,3′-diaminodiphenylether, 3,4′-diaminodiphenylether, 1,5-diaminonaphthalene, 4, , 4'-diaminodiphenyldiethylsilane, 4,4'-diaminodiphenylsilane, 4,4'-diaminodiphenylethylphosphine oxide, 4,4'-diaminodiphenyl N-methylamine, 4,4'-diaminodiphenyl N- Phenylamine, 1 4- diaminobenzene (p- phenylene diamine), 1,3-diaminobenzene, 1,2-diaminobenzene, and analogues thereof, or the like can be suitably used.

  These diamines may be used alone, or two or more kinds may be mixed at an arbitrary ratio and used as a mixture.

  In particular, it is preferable to use 4,4'-diaminodiphenyl ether and p-phenylenediamine as the diamine. These compounds may be used alone, or two or more kinds may be mixed at an arbitrary ratio and used as a mixture.

  In the production of the polyamic acid, an amide solvent such as N, N-dimethylformamide, N, N-dimethylacetamide, or N-methyl-2-pyrrolidone can be suitably used as the organic solvent. .

  These organic solvents may be used alone, or two or more kinds thereof may be mixed at an arbitrary ratio and used as a mixture.

  In particular, it is preferable to use N, N-dimethylformamide or N, N-dimethylacetamide as the organic solvent. These organic solvents may be used alone, or two or more kinds thereof may be mixed at an arbitrary ratio and used as a mixture.

  Other conditions at the time of producing the polyamic acid solution are not particularly limited. Specifically, the composition ratio of the monomer solution prepared for the polymerization of the polyamic acid, the temperature conditions for polymerizing the polyamic acid, the order of addition of the monomers, the stirring conditions of the monomer solution, etc. The conditions are sufficient as long as the acid solution can be synthesized, and conventionally known conditions can be appropriately applied.

  Subsequently, the above polyamic acid is imidized (dehydrated and cyclized) to form a polyimide film. Specifically, for example, a polyimide film is obtained by casting or coating a polyamic acid solution on a support and curing the polyamic acid solution using at least one of a thermal curing method and a chemical curing method.

  The thermal cure method is a method in which an imidization reaction proceeds by heating alone without using a dehydrating ring-closing agent or the like. Conventionally known conditions can be suitably used for the heating temperature and other conditions, and are not particularly limited.

  The chemical curing method is a method in which a chemical additive and preferably a catalyst are allowed to act on a polyamic acid solution to advance an imidization reaction. Examples of chemical additives include aliphatic acid anhydrides, aromatic acid anhydrides, N, N′-dialkylcarbodiimides, lower aliphatic halides, halogenated lower aliphatic halides, halogenated lower fatty acid anhydrides, aryls A phosphonic acid dihalide or a thionyl halide can be preferably used.

  Although the usage-amount of a chemical additive is not specifically limited, It is preferable to exist in the range of 0.5 molar equivalent or more and 5.0 molar equivalent or less with respect to 1 mol of amic acid in a polyamic acid. If the amount of the chemical additive used is too small, imidization is delayed and productivity may be deteriorated. On the other hand, if the amount of the chemical additive used is too large, the mechanical properties of the finally obtained polyimide film deteriorate, or imidation becomes too fast, so that the polyamic acid solution can be cast and applied to the support. It becomes difficult.

  The catalyst is used with a chemical additive in order to effectively perform imidization. As the catalyst, for example, an aliphatic tertiary amine, an aromatic tertiary amine, a heterocyclic tertiary amine, or the like is used. In particular, a compound selected from heterocyclic tertiary amines is preferably used as the catalyst. More specifically, quinoline, isoquinoline, β-picoline, pyridine or the like is preferably used as the catalyst.

  Although the usage-amount of a catalyst is not specifically limited, For example, it exists in the range of 0.1 mol equivalent or more and 2 mol equivalent or less with respect to 1 mol of amic acid in polyamic acid, and 0.2 mol equivalent or more and 1.5 mol equivalent It is preferably within the following range, and more preferably within the range of 0.3 molar equivalent or more and 1.0 molar equivalent or more. If the amount of the catalyst used is too small, imidization tends to be difficult to proceed. On the other hand, when the amount of the catalyst used is too large, imidization proceeds rapidly, and it becomes difficult to cast and apply the polyamic acid solution onto the support.

  As the support, for example, a glass plate, an aluminum foil, an endless stainless belt, a stainless drum, or the like can be used. The size of the support is not particularly limited. Further, the conditions for casting or coating the polyamic acid solution on the support are not particularly limited.

(2-2) Addition of filler The filler is added to the polyamic acid solution before imidization or the imidized polyimide film.

  In the present embodiment, a filler having an average particle size of 0.002 μm or more and 0.5 μm or less is used. As the filler, for example, a dry inorganic filler such as silica, calcium hydrogen phosphate or alumina is used. These inorganic fillers may be used alone or as a mixture in which two or more kinds are mixed.

  The average particle size of the filler is preferably 0.002 μm or more and 0.4 μm or less, more preferably 0.002 μm or more and 0.2 μm or less, and further preferably 0.005 μm or more and 0.05 μm or less. .

  When the particle size of the filler is too large, erroneous recognition is likely to occur in the inspection process of the wiring pattern 6 as described later. On the other hand, if the particle size of the filler is too small, the slipperiness of the wiring pattern 6 with respect to the transport roller cannot be sufficiently improved.

  The amount of filler added in the polyamic acid solution or polyimide film is preferably 0.05 wt% or more and 60 wt% or less, more preferably 0.1 wt% or more and 50 wt% or less, and 0.3 wt% or more and 40 wt% or less. More preferably, it is% or less.

  If the amount of filler added is too small, the slipperiness of the wiring pattern 6 with respect to the transport roller cannot be sufficiently improved. On the other hand, if the added amount of the filler is too large, secondary agglomeration is likely to occur, and erroneous recognition is likely to occur in the inspection process of the wiring pattern 6 as described later.

  When the filler is added to the polyamic acid solution before imidization, for example, a method of polymerizing polyamic acid using a mellar in which the filler is dispersed as a polymerization solvent is used. In this case, when the preparation of the polyamic acid solution is completed, a polyamic acid solution in which the filler is dispersed (hereinafter referred to as filler-dispersed polyamic acid solution) is obtained.

  Also, a method of preparing a polyamic acid solution in which a filler or a filler slurry is added in the middle of polymerization to disperse the filler, or a slurry of the polyamic acid solution and the filler immediately before casting or coating the polyamic acid solution on the support A method of mixing and the like may be used.

  When using a thermal curing method in the step of imidizing the polyamic acid solution, the filler-dispersed polyamic acid solution can be heated as it is.

  Moreover, when using a chemical curing method in the step of imidizing the polyamic acid solution, a curing agent containing a chemical additive and a catalyst may be added to the filler-dispersed polyamic acid solution. A slurry in which a filler is dispersed in this curing agent may be prepared and added to the polyamic acid solution.

  When adding a filler to a polyimide film, for example, a filler dispersion liquid in which a filler is dispersed may be prepared, and this filler dispersion liquid may be applied to the polyimide film.

(3) Inspection Process Next, the inspection process for the wiring pattern 6 will be described. After the printed circuit board 100 is manufactured as described above, a defect of the wiring pattern 6 is detected in the inspection process.

  FIG. 3 is a schematic diagram for explaining the inspection process of the wiring pattern 6. As shown in FIG. 3, in the inspection process, inspection light is irradiated onto the printed circuit board 100 by the light irradiation unit 55, and the reflected light is received by the light receiving unit 56. A defect in the wiring pattern 6 is detected based on the light received by the light receiving unit 56.

  However, when a material having high light transmittance such as polyimide is used as the material of the insulating layer 1, the light irradiated on the printed circuit board 100 may pass through the insulating layer 1. In that case, the following problems occur.

  FIG. 4 is a schematic side view for explaining a problem that occurs in the inspection process.

  As shown in FIG. 4, the light L <b> 1 irradiated on the wiring pattern 6 is reflected by the wiring pattern 6. On the other hand, the light L2 applied to the region on the insulating layer 1 where the wiring pattern 6 is not formed passes through the insulating layer 1 and reaches the ground layer 2 disposed on the lower surface side of the insulating layer 1. Then, the light L2 is reflected by the ground layer 2.

  In this case, the light L2 reflected by the ground layer 2 may be erroneously recognized as the light L1 reflected by the wiring pattern 6. Thereby, the defect of the wiring pattern 6 cannot be accurately detected. Such a problem is caused by light having a wavelength larger than 500 nm being transmitted through polyimide which is a material of the insulating layer 1.

  The same problem occurs when a reinforcing layer or another wiring pattern is formed on the lower surface side of the insulating layer 1 instead of the ground layer 2.

  Therefore, in the present embodiment, violet light, blue light, or blue-green light having a maximum light intensity in a wavelength region of 400 nm to 500 nm is used as inspection light in the inspection process. In this case, the light L2 irradiated on the insulating layer 1 is prevented from being transmitted through the insulating layer 1 by using the light having the maximum light intensity in the wavelength region of 500 nm or less.

  Further, when the printed circuit board 100 is irradiated with light having a wavelength smaller than 400 nm, the surface of the insulating layer 1 may be modified. Therefore, the use of light having the maximum light intensity in the wavelength region of 400 nm or more can prevent the surface of the insulating layer 1 from being modified.

  However, if the particle size of the filler contained in the insulating layer 1 is too large, the light L2 may be reflected by the filler in the insulating layer 1. In that case, the reflected light from the filler may be erroneously recognized as the reflected light from the wiring pattern 6.

  Therefore, in the present embodiment, as described above, a filler having an average particle diameter of 0.002 μm or more and 0.5 μm or less is used. In this case, the light applied to the printed circuit board 100 is prevented from being reflected by the filler in the insulating layer 1.

  As the light irradiation unit 55, a violet light emitting diode, a blue light emitting diode, a violet laser diode, a blue laser diode, or the like that emits light having a maximum light intensity in a wavelength region of 400 nm to 500 nm can be used.

  As the light receiving unit 56, a camera or an area sensor that can receive light in a wavelength region of 400 nm to 500 nm can be used. In particular, it is preferable to use a camera, an area sensor, or the like that has higher sensitivity to light in the wavelength region of 400 nm to 500 nm than the sensitivity to light in the wavelength region greater than 500 nm. Specifically, it is preferable to use a purple light photographing camera or a blue light photographing camera. In addition, image processing may be performed in which an image including only light of 400 nm to 500 nm is extracted from the captured image.

  In addition, it is preferable that the maximum value of the light intensity in the wavelength region of 400 nm or more and 500 nm or less is 10 times or more with respect to the maximum value of the light intensity in the wavelength region of greater than 500 nm. Moreover, it is preferable that the maximum value of the light intensity in the wavelength region of 400 nm or more and 500 nm or less is 10 times or more with respect to the maximum value of the light intensity in the wavelength region of less than 400 nm.

  Furthermore, it is more preferable to use light having a maximum light intensity in a wavelength region of 425 nm or more and 475 nm or less.

(4) Effects of the present embodiment As described above, in the present embodiment, the filler having an average particle diameter of 0.002 μm or more and 0.5 μm or less is added to the insulating layer 1 and, in the inspection process, 400 nm or more and 500 nm. Light having the maximum light intensity in the following wavelength region is used as inspection light.

  In this case, the slipperiness of the wiring pattern 6 is sufficiently improved by the filler. Further, in the inspection process, the reflected light from the ground layer 2 or the reflected light from the filler is prevented from being erroneously recognized as reflected light from the wiring pattern 6.

  Accordingly, the printed circuit board 100 can be smoothly conveyed by the roll-to-roll method, and a defect of the wiring pattern 6 can be accurately detected in the inspection process.

(5) Examples and Comparative Examples A printed circuit board 100 was produced using various fillers having different average particle diameters, and the wiring pattern 6 was inspected.

  In Table 1, the average particle diameter of the filler used in Examples 1-7 and Comparative Examples 1-4 is shown.

  The thickness of the insulating layer 1 was 35 μm, and the thickness of the wiring pattern 6 was 8.5 μm. Further, as the inspection light, light having a wavelength of 450 nm and light having a wavelength of 500 nm were used.

(5-1) Examples 1-8
In Examples 1 to 7, a filler having an average particle diameter of 0.003 μm or more and 0.5 μm or less was added to the insulating layer 1.

(5-2) Comparative Examples 1-4
In Comparative Example 1, no filler was added to the insulating layer 1. In Comparative Examples 2 to 4, a filler having an average particle size of 0.7 μm or more and 1 μm or less was added to the insulating layer 1.

(5-3) Evaluation Table 1 shows the static friction coefficient and the dynamic friction coefficient between the wiring pattern 6 and the conveyance roller in Examples 1 to 7 and Comparative Examples 1 to 4, and Examples 1 to 7 and the comparison. In Examples 1 to 4, whether or not the reflected light from the filler is erroneously recognized as reflected light from the wiring pattern 6 is shown.

  In Examples 1 to 8, the friction between the wiring pattern 6 and the conveyance roller was sufficiently reduced. Further, when the wiring pattern 6 was inspected, the reflected light from the filler was hardly erroneously recognized as the reflected light from the wiring pattern 6.

  In Comparative Example 1, since no filler was added to the insulating layer 1, the reflected light from the filler was not erroneously recognized as the reflected light from the wiring pattern 6 when the wiring pattern 6 was inspected. Friction with the transport roller increased.

  In Comparative Examples 2 to 4, although the friction between the wiring pattern 6 and the transport roller was reduced, reflected light from the filler was erroneously recognized as reflected light from the wiring pattern 6 when the wiring pattern 6 was inspected.

  Accordingly, the filler having an average particle diameter of 0.002 μm or more and 0.5 μm or less is added to the insulating layer 1, so that the slipping property of the wiring pattern 6 with respect to the transport roller is sufficiently improved, and the reflected light from the filler is reduced. It has been found that the occurrence of erroneous recognition of the reflected light by the wiring pattern 6 is prevented.

  The present invention can be effectively used when manufacturing various printed circuit boards.

It is a manufacturing process figure which shows the outline | summary of the manufacturing method of the printed circuit board which concerns on this Embodiment. It is a manufacturing process figure which shows the outline | summary of the manufacturing method of the printed circuit board which concerns on this Embodiment. It is a schematic diagram for demonstrating an inspection process. It is a typical side view for demonstrating the problem which generate | occur | produces in an inspection process.

Explanation of symbols

1 Insulating layer
2 Ground layer
3 Conductive thin film
4 Photoresist 5 Conductor layer 6 Wiring pattern 55 Light irradiation part 56 Light receiving part L1, L2 Light

Claims (4)

Forming a polyimide layer containing a filler having an average particle size of 0.002 μm or more and 0.5 μm or less;
Forming a wiring pattern on the polyimide layer;
Irradiating the polyimide layer with light having a maximum light intensity in the wavelength region of 400 nm or more and 500 nm or less by the light irradiator and detecting the defect of the wiring pattern by receiving the reflected light by the light receiver. A method for manufacturing a printed circuit board, comprising: 2. The method of manufacturing a printed circuit board according to claim 1, wherein the filler includes at least one of silica, calcium phosphate, calcium hydrogen phosphate, and alumina. 3. The step of inspecting the defect of the wiring pattern, wherein the light irradiating unit irradiates the polyimide layer with light having a maximum light intensity in a wavelength region of 425 nm or more and 475 nm or less. A method for manufacturing a printed circuit board. 4. The light-receiving portion having a higher sensitivity to light in a wavelength region of 400 nm or more and 500 nm or less than sensitivity to light in a wavelength region greater than 500 nm is used in the step of inspecting the defect of the wiring pattern. The manufacturing method of the printed circuit board in any one of.

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