Printed circuit board and method for manufacturing the same
By using vacuum hot pressing technology of insulating layer on printed circuit boards, the problem of insufficient insulation characteristics after increasing wiring density is solved, and a high-density and good insulation printing circuit board manufacturing method is realized.
Patent Information
- Application Number
- CN202210663132.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Priority Date
- 2016-10-12
- Filing Date
- 2017-10-05
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2037-10-05
AI Technical Summary
After the wiring density of existing printed circuit boards increases, the insulation characteristics between the wiring lines are insufficient, resulting in insufficient insulation effect.
Using a base film with insulating characteristics and a conductive pattern, the insulating layer is filled between the wiring parts through a vacuum hot pressing step, ensuring that the filling area ratio of the insulating layer reaches more than 95%, and achieving high wiring density and good insulation characteristics.
Without increasing the thickness of the insulation layer and the printed circuit board thickness, the wiring density and insulation characteristics are improved to ensure the high density and good insulation performance of the printed circuit board.
Smart Images
Figure CN114945242B_ABST
Abstract
Description
[0001] This application is a divisional application of the invention patent application filed on October 5, 2017, with the invention name “Printed circuit board and its manufacturing method” and application number PCT / JP2017 / 036210 (domestic application number: 2017800634352). Technical Field
[0002] The present invention relates to a printed circuit board and a method for manufacturing the same.
[0003] This application claims priority from Japanese Patent Application No. 2016-201012 filed on October 12, 2016, and the entire contents of this Japanese Patent Application are incorporated herein by reference. Background Art
[0004] As electronic devices are reduced in size and weight, printed circuit boards have been widely used. Such printed circuit boards generally have a structure in which a conductive pattern is formed on a base film containing polyimide or the like as a main component, and the conductive pattern is covered with an insulating layer such as a solder resist or the like (see Japanese Unexamined Patent Application Publication No. 2013-004625).
[0005] Reference List
[0006] Patent Literature
[0007] PTL 1: Japanese Unexamined Patent Application Publication No. 2013-004625 Summary of the invention
[0008] A printed circuit board according to an embodiment of the present invention includes: a base film having insulating properties; a conductive pattern stacked on at least one surface side of the base film and including a plurality of wiring portions arranged adjacent to each other; and an insulating layer covering an outer surface of the base film and an outer surface of the conductive pattern, wherein the plurality of wiring portions have an average spacing of 1 μm or more and 20 μm or less and an average height of 30 μm or more and 120 μm or less, and a filling area ratio of the insulating layer between the plurality of wiring portions adjacent to each other in a cross-sectional view is 95% or more.
[0009] According to an embodiment of the present invention, a method for manufacturing a printed circuit board includes: a stacking step of stacking a conductive pattern on at least one surface side of a base film, the base film having insulating properties, and the conductive pattern including a plurality of wiring portions arranged adjacent to each other; a laminating step of laminating an insulating film on an outer surface of the base film and an outer surface of the conductive pattern; and a vacuum hot pressing step of vacuum hot pressing the stacked body laminated with the insulating film, wherein the plurality of wiring portions have an average spacing of greater than 1 μm and less than 20 μm and an average height of greater than 30 μm and less than 120 μm. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 is a schematic cross-sectional view of a printed circuit board according to an embodiment of the present invention.
[0011] Figure 2 is a flowchart illustrating a method for manufacturing a printed circuit board according to an embodiment of the present invention. DETAILED DESCRIPTION
[0012] [Problems to be Solved by the Present Disclosure]
[0013] In recent years, as the size of electronic devices has further decreased, the wiring density of printed circuit boards has also increased. The increase in wiring density has resulted in extremely small wiring pitches (intervals). Therefore, in existing printed circuit boards, areas where no insulating layer is filled between wiring lines may be generated near the surface of the base film, which may result in insufficient insulation properties between the wiring lines.
[0014] The present invention has been made in view of the above circumstances. An object of the present invention is to provide a printed circuit board having a relatively high wiring density and having good insulation properties between wiring lines and a method for manufacturing the printed circuit board.
[0015] [Beneficial Effects of the Present Disclosure]
[0016] The printed circuit board and the method for manufacturing the printed circuit board of the present invention can improve both the wiring density and the insulation characteristics between the wiring lines.
[0017] [Description of Embodiments of the Invention]
[0018] A printed circuit board according to an embodiment of the present invention includes: a base film having insulating properties; a conductive pattern stacked on at least one surface side of the base film and including a plurality of wiring portions arranged adjacent to each other; and an insulating layer covering an outer surface of the base film and an outer surface of the conductive pattern, wherein the plurality of wiring portions have an average spacing of 1 μm or more and 20 μm or less and an average height of 30 μm or more and 120 μm or less, and a filling area ratio of the insulating layer between the plurality of wiring portions adjacent to each other in a cross-sectional view is 95% or more.
[0019] The printed circuit board has an average pitch and an average height of the wiring parts within the above ranges and has a relatively high wiring density, and the printed circuit board has a filling area ratio of the insulating layer between the wiring parts of 95% or more, and thus also has good insulation properties. That is, the printed circuit board has a relatively high wiring density and good insulation properties between the wiring lines.
[0020] The average minimum distance between the outer surface of each wiring portion and the outer surface of the insulating layer is preferably greater than 0 and less than 20 μm. When the average minimum distance between each wiring portion and the insulating layer is within the above range, the insulating properties can be maintained without increasing the thickness of the insulating layer and extending the thickness of the printed circuit board.
[0021] The insulating layer is preferably a solder resist. When the solder resist is used as the insulating layer, filling of the insulating layer can be easily and reliably performed at the above-mentioned filling area ratio.
[0022] According to another embodiment of the present invention, a method for manufacturing a printed circuit board includes: a stacking step of stacking a conductive pattern on at least one surface side of a base film, the base film having insulating properties, and the conductive pattern including a plurality of wiring portions arranged adjacent to each other; a laminating step of laminating an insulating film on an outer surface of the base film and an outer surface of the conductive pattern; and a vacuum hot pressing step of vacuum hot pressing the stacked body laminated with the insulating film, wherein the plurality of wiring portions have an average spacing of greater than 1 μm and less than 20 μm and an average height of greater than 30 μm and less than 120 μm.
[0023] According to the method for manufacturing a printed circuit board, by performing vacuum heat pressing after laminating an insulating film on the outer surface of a conductive pattern, gaps between wiring parts having a relatively high wiring density can be easily and reliably filled with an insulating layer. Therefore, the method for manufacturing a printed circuit board can provide a printed circuit board having a relatively high wiring density and good insulation characteristics.
[0024] In the vacuum heat pressing step, the heating temperature is preferably 50° C. to 150° C., and the pressing time is preferably 5 seconds to 20 seconds. When the pressing temperature and time in the vacuum heat pressing are within the above ranges, the gaps between the wiring parts can be easily and reliably filled with the insulating layer.
[0025] The term "filling area ratio" means: in a cross section perpendicular to the longitudinal direction of the wiring part, in a region between side edges of adjacent wiring parts in a direction parallel to the surface of the printed circuit board, the ratio of the area filled with the insulating layer to the entire area of the region.
[0026] [Details of Embodiments of the Invention]
[0027] Hereinafter, a printed circuit board and a method for manufacturing the printed circuit board according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. Regarding the terms "front and back" of the printed circuit board according to the embodiment, in the thickness direction of the printed circuit board, the side stacked with the conductive pattern is called "front", and the other side opposite to the side stacked with the conductive pattern is called "back", and these front and back do not mean the front and back of the printed circuit board relative to the use state of the printed circuit board.
[0028] [Printed Circuit Board]
[0029] Figure 1 The printed circuit board shown mainly includes a base film 1 having insulating properties, a conductive pattern 2 stacked on one surface side (front surface side) of the base film 1 , and an insulating layer 3 covering the outer surfaces of the base film 1 and the conductive pattern 2 .
[0030] <Base film>
[0031] The base film 1 is a layer made of a synthetic resin and having electrical insulating properties. The base film 1 also serves as a base on which the conductive pattern 2 is formed. The base film 1 may have flexibility, in which case the printed circuit board serves as a flexible printed circuit board.
[0032] The material of the base film 1 is not particularly limited as long as the material has insulating properties. A synthetic resin film having a low dielectric constant and formed into a sheet shape can be used. Examples of the main components of the synthetic resin film include polyimide, polyethylene terephthalate, liquid crystal polymer, and fluororesin. The term "main component" refers to a component with the highest content, for example, a component with a content of 50% by mass or more in the material.
[0033] The lower limit of the average thickness of the base film 1 is preferably 5 μm and more preferably 10 μm. The upper limit of the average thickness of the base film 1 is preferably 50 μm and more preferably 40 μm. When the average thickness of the base film 1 is less than the lower limit, the base film 1 may have insufficient insulation strength. When the average thickness of the base film 1 exceeds the upper limit, the thickness of the printed circuit board may be unnecessarily increased.
[0034] <Conductive Pattern>
[0035] The conductive pattern 2 is a layer made of a material having conductivity, and includes a plurality of wiring portions 2a arranged adjacent to each other. The wiring portion 2 is, for example, a wiring line forming a coil pattern. The conductive pattern 2 may include patterns other than the wiring portion 2a, for example, a pattern of a pad portion, etc. The conductive pattern 2 may be directly stacked on the surface of the base film 1 or have an adhesive layer therebetween.
[0036] The material (main component) of the conductive pattern 2 is not particularly limited as long as the material has conductivity. The material preferably has low resistance. The conductive pattern 2 can be formed of, for example, copper or silver. The conductive pattern 2 can be plated with, for example, gold, silver, tin or nickel.
[0037] The lower limit of the average spacing d1 of multiple wiring parts 2a is 1μm, more preferably 3μm, and even more preferably 5μm. On the other hand, the upper limit of the average spacing d1 of multiple wiring parts 2a is 20μm, more preferably 15μm, and even more preferably 10μm. When the average spacing d1 of multiple wiring parts 2a is less than the lower limit, a short circuit may occur between the wiring parts 2a. On the contrary, when the average spacing d1 of multiple wiring parts 2a exceeds the upper limit, the requirements for wiring density may not be met. In addition, the gaps between the wiring parts 2a can also be easily filled with an insulating layer by existing methods, so the beneficial effects of the present invention may not be fully achieved. The term "average spacing of multiple wiring parts" refers to: a value determined by averaging the minimum distance between the facing side edges of wiring parts adjacent to each other in a cross section perpendicular to the longitudinal direction of the wiring part in the longitudinal direction of the wiring part.
[0038] The lower limit of the average height h of the plurality of wiring parts 2a is 30 μm, more preferably 35 μm, and even more preferably 40 μm. On the other hand, the upper limit of the average height h of the plurality of wiring parts 2a is 120 μm, more preferably 100 μm, and even more preferably 80 μm. When the average height h of the plurality of wiring parts 2a is less than the lower limit, the wiring parts 2a may have too high a resistance as the wiring density increases. In addition, the gaps between the wiring parts 2a can also be easily filled with an insulating layer by existing methods, so the beneficial effects of the present invention may not be fully achieved. On the contrary, when the average height h of the plurality of wiring parts 2a exceeds the upper limit, the thickness of the printed circuit board may be unnecessarily increased. The term "average height of the plurality of wiring parts" refers to: a value determined by averaging the maximum height of each wiring part in a cross section perpendicular to the longitudinal direction of the wiring part in the longitudinal direction of the wiring part.
[0039] The lower limit of the average width of multiple wiring parts 2a is preferably 10μm, more preferably 15μm, and even more preferably 20μm. On the other hand, the upper limit of the average width of multiple wiring parts 2a is preferably 40μm, more preferably 35μm, and even more preferably 30μm. When the average width of multiple wiring parts 2a is less than the lower limit, manufacturing difficulties may occur. On the contrary, when the average width of multiple wiring parts 2a exceeds the upper limit, the requirements for wiring density may not be met. The term "average width of multiple wiring parts" refers to: a value determined by averaging the width of the bottom surface (interface with the base film) of each wiring part in a cross section perpendicular to the longitudinal direction of the wiring part in the longitudinal direction of the wiring part.
[0040] The lower limit of the average aspect ratio of multiple wiring parts 2a is preferably 1.2, more preferably 1.4, and even more preferably 1.6. On the other hand, the upper limit of the average aspect ratio of multiple wiring parts 2a is preferably 5.0, more preferably 4.0, and even more preferably 3.0. When the average aspect ratio of multiple wiring parts 2a is lower than the lower limit, the requirement for wiring density may not be met. On the contrary, when the average aspect ratio of multiple wiring parts 2a exceeds the upper limit, manufacturing difficulties may occur. The term "aspect ratio of multiple wiring parts" refers to the ratio of average height h to average width.
[0041] The lower limit of the ratio (h / d1) of the average height h of the plurality of wiring portions 2a to the average spacing d1 is preferably 2.0, more preferably 3.0, and even more preferably 4.0. On the other hand, the upper limit of the ratio (h / d1) is preferably 12.0, more preferably 10.0, and even more preferably 8.0. When the ratio (h / d1) is lower than the lower limit, the requirement for wiring density may not be met. On the contrary, when the ratio (h / d1) exceeds the upper limit, the thickness of the printed circuit board may be unnecessarily increased.
[0042] Among the wiring portions 2a forming the coil pattern, the cross-sectional areas (average width, average height, and average aspect ratio) of the plurality of wiring portions 2a are preferably equal to one another.
[0043] like Figure 1 As shown, each wiring portion 2a has a tapered portion whose width gradually decreases toward the base film 1 on the bottom surface portion on the base film 1 side. The tapered portion is formed by secondary plating when the wiring portion 2a is formed by further performing secondary plating on a pattern formed by a semi-additive method. In particular, in such a wiring portion 2a, the tapered portion is unlikely to be filled with an insulating layer, and a void is easily formed in the tapered portion.
[0044] <Insulation layer>
[0045] The insulating layer 3 is a layer that mainly protects the conductive pattern 2 in the printed circuit board. The material of the insulating layer 3 is not particularly limited as long as the material has insulating properties. Examples of materials that can be used include materials containing resins (such as polyimide, epoxy resin, phenolic resin, acrylic resin, polyester, thermoplastic polyimide, polyethylene terephthalate, fluororesin or liquid-crystalline polymer) as main components. Among them, thermoplastic resins are preferred. In particular, the use of solder resist as the insulating layer 3 enables the insulating layer 3 to be easily formed by the following manufacturing method. In addition, the insulating layer 3 is preferably formed by laminating resin films.
[0046] The lower limit of the melting point of the resin used as the main component of the insulating layer 3 or the glass transition point when there is no melting point (hereinafter, also referred to as "melting point or glass transition point T") is preferably 30°C, more preferably 40°C, and even more preferably 50°C. On the other hand, the upper limit of the melting point or glass transition point T is preferably 200°C, more preferably 190°C, and even more preferably 180°C. When the melting point or glass transition point T is lower than the lower limit, the insulating layer 3 may have insufficient heat resistance. On the other hand, when the melting point or glass transition point T exceeds the upper limit, it may be difficult to achieve the filling area ratio described below. The term "melting point" means the melting point peak measured by a differential scanning calorimeter (DSC) according to JIS-K-7121 (2012). The term "glass transition point" means the midpoint glass transition point measured by a differential scanning calorimeter (DSC) according to JIS-K-7121 (2012).
[0047] The lower limit of the filling area ratio of the insulating layer 3 between the plurality of wiring portions 2a adjacent to each other in the cross-sectional view is 95%, more preferably 98%, and still more preferably 99%. In addition, the filling area ratio is preferably 100%, that is, there is substantially no void (bubble) between the insulating layer 3 and the base film 1.
[0048] The lower limit of the average thickness of the insulating layer 3 (the average distance from the front surface of the base film 1 to the outer surface of the insulating layer 3) is preferably 40 μm, more preferably 50 μm, and even more preferably 60 μm. On the other hand, the upper limit of the average thickness of the insulating layer 3 is preferably 90 μm, more preferably 80 μm, and even more preferably 70 μm. When the average thickness of the insulating layer 3 is less than the lower limit, the insulating property may become insufficient. On the contrary, when the average thickness of the insulating layer 3 exceeds the upper limit, the thickness of the printed circuit board may be unnecessarily increased.
[0049] The average minimum distance d2 between the outer surface of each wiring portion 2a and the outer surface of the insulating layer 3 is greater than 0. The lower limit of the average minimum distance d2 is preferably 0.1 μm, more preferably 0.5 μm, and even more preferably 1 μm. On the other hand, the upper limit of the average minimum distance d2 is preferably 20 μm, more preferably 15 μm, and even more preferably 10 μm. When the average minimum distance d2 is less than the lower limit, the insulation properties may become insufficient. On the contrary, when the average minimum distance d2 exceeds the upper limit, the thickness of the printed circuit board may increase unnecessarily. That is, when the average minimum distance d2 in the printed circuit board is within the above range, the thickness of the entire printed circuit board can be reduced while maintaining the insulation properties due to the insulating layer 3. The term "average minimum distance between the outer surface of each wiring portion and the outer surface of the insulating layer" refers to a value determined by averaging the minimum distance between the outer surface of the insulating layer and the surface of each wiring portion on the opposite side of the base film in the longitudinal direction of the wiring portion.
[0050] [Method for manufacturing printed circuit board]
[0051] like Figure 2 As shown, the method for manufacturing a printed circuit board mainly includes: a stacking step S1, stacking a conductive pattern on at least one surface side of a base film, the base film has an insulating property, and the conductive pattern includes a plurality of wiring parts arranged adjacent to each other; a stacking step S2, stacking an insulating film on the outer surface of the base film and the outer surface of the conductive pattern; and a vacuum hot pressing step S3, vacuum hot pressing the stacked body stacked with the insulating film.
[0052] <Stacking steps>
[0053] In the stacking step S1, a conductive pattern including a plurality of wiring portions arranged adjacent to each other is stacked on at least one surface side of the base film. A known method can be used as a method for stacking conductive patterns. A subtractive method, a semi-additive method, etc. can be used. In particular, a conductive pattern with a high wiring density can be efficiently obtained by using a semi-additive method.
[0054] <Layering Steps>
[0055] In the stacking step S2, an insulating film forming an insulating layer is stacked on the outer surface of the stacked body obtained in the stacking step S1 and including the base film and the conductive pattern. The main component of the insulating film may be the same as the main component of the insulating layer of the printed circuit board. The insulating film preferably has flexibility.
[0056] The average thickness of the insulating film is appropriately designed according to the thickness of the conductive pattern and the thickness of the insulating layer to be formed. The lower limit of the average thickness is preferably 30 μm, and more preferably 40 μm.
[0057] On the other hand, the upper limit of the average thickness of the insulating film is preferably 80 μm, and more preferably 60 μm.
[0058] <Vacuum heat pressing step>
[0059] In the vacuum hot pressing step S3, the resulting product obtained by laminating the insulating film on the stacked body including the base film and the conductive pattern in the laminating step S2 is vacuum hot pressed. The vacuum hot pressing can be performed by a known press. The vacuum hot pressing is performed in batches for the continuous sheet-like stacked body.
[0060] The lower limit of the heating temperature in vacuum heat pressing is preferably 50° C., more preferably 60° C., and still more preferably 70° C. On the other hand, the upper limit of the heating temperature is preferably 150° C., more preferably 130° C., and still more preferably 110° C.
[0061] The lower limit of the heating time in the vacuum heat pressing is preferably 5 seconds, and more preferably 8 seconds. On the other hand, the upper limit of the heating time is preferably 20 seconds, and more preferably 15 seconds.
[0062] When the heating temperature or heating time is less than the lower limit, the gaps between the wiring parts are not sufficiently filled with the insulating layer, which may lead to reduced insulation properties. Conversely, when the heating temperature or heating time exceeds the upper limit, for example, the base film may be deformed or deteriorated.
[0063] The lower limit of the pressurization pressure in the vacuum hot pressing is preferably 0.3 MPa, more preferably 0.4 MPa, and even more preferably 0.5 MPa. On the other hand, the upper limit of the pressurization pressure is preferably 1.3 MPa, more preferably 1.2 MPa, and even more preferably 1.1 MPa. When the pressurization pressure is lower than the lower limit, the gap between the wiring parts is not fully filled by the insulating layer, which may cause the insulation characteristics to decrease. On the contrary, when the pressurization pressure exceeds the upper limit, for example, the base film may be deformed or broken.
[0064] After the vacuum heat pressing step S3, a step of forming an opening for electrical connection in the insulating layer may be performed. When a dry film of a solder resist is used as the insulating film, the opening may be easily formed through steps such as exposure and development.
[0065] <Advantages>
[0066] The printed circuit board has an average spacing and an average height of wiring parts within the above range and has a relatively high wiring density, and the filling area ratio of the insulating layer between the wiring parts of the printed circuit board is 95% or more, so it also has good insulation properties. That is, the printed circuit board has a relatively high wiring density and good insulation properties between wiring lines. In addition, the method for manufacturing a printed circuit board can provide such a printed circuit board relatively easily compared to the case where the insulating layer is formed by coating insulating ink.
[0067] Since the wiring density in the printed circuit board can be increased, the printed circuit board can be suitably used as an actuator, an antenna, a transformer, etc. of a compact device.
[0068] [Other embodiments]
[0069] It should be understood that the embodiments disclosed herein are illustrative and non-restrictive in all aspects. The scope of the present invention is not limited to the construction of these embodiments, and is defined by the claims described below. The scope of the present invention is intended to cover all modifications within the meaning and scope of the equivalents of the claims.
[0070] In the above embodiment, a printed circuit board has been described, which includes a single base film and a single-layer conductive pattern stacked on one surface of the base film. A printed circuit board having a conductive pattern stacked on each surface of a single base film is also within the intended scope of the present invention. In addition, the printed circuit board may be a multilayer printed circuit board including a plurality of base films, each of which has a conductive pattern on one or both surfaces.
[0071] The insulating layer of the printed circuit board can be formed by coating and drying the resin composition (insulating ink).
[0072] Reference numerals list
[0073] 1 Basement membrane
[0074] 2 Conductive pattern
[0075] 2a Wiring section
[0076] 3 Insulation layer
[0077] S1 stacking steps
[0078] S2 Cascading Steps
[0079] S3 Vacuum hot pressing step
Claims
1. A printed circuit board, comprising: a base film, which has insulating properties; a conductive pattern stacked on at least one surface side of the base film and including a plurality of wiring portions arranged adjacent to each other; as well as an insulating layer covering an outer surface of the base film and an outer surface of the conductive pattern, wherein the wiring portion has an average pitch of 1 μm to 20 μm and an average height of 30 μm to 120 μm, The ratio of the average height to the average pitch of the wiring portion is greater than or equal to 2.0 and less than or equal to 12.0, The average aspect ratio of the wiring portion is greater than 1.2, The average width of the wiring portion is 10 μm or more and 40 μm or less, and A filling area ratio of the insulating layer between the wiring portions adjacent to each other in a cross-sectional view is 95% or more.
2. A printed circuit board, comprising: a base film, which has insulating properties; a conductive pattern stacked on at least one surface side of the base film and including a plurality of wiring portions arranged adjacent to each other; as well as an insulating layer covering an outer surface of the base film and an outer surface of the conductive pattern, wherein the wiring portion has an average pitch of 1 μm to 20 μm and an average height of 30 μm to 120 μm, The ratio of the average height to the average pitch of the wiring portion is greater than or equal to 3.0 and less than or equal to 10.0, The average aspect ratio of the wiring portion is greater than 1.2, The average width of the wiring portion is 10 μm or more and 40 μm or less, and A filling area ratio of the insulating layer between the wiring portions adjacent to each other in a cross-sectional view is 95% or more.
3. A printed circuit board, comprising: a base film, which has insulating properties; a conductive pattern stacked on at least one surface side of the base film and including a plurality of wiring portions arranged adjacent to each other; as well as an insulating layer covering an outer surface of the base film and an outer surface of the conductive pattern, wherein the wiring portion has an average pitch of 1 μm to 20 μm and an average height of 30 μm to 120 μm, The ratio of the average height to the average pitch of the wiring portion is 4.0 or more and 8.0 or less, The average aspect ratio of the wiring portion is greater than 1.2, The average width of the wiring portion is 10 μm or more and 40 μm or less, and A filling area ratio of the insulating layer between the wiring portions adjacent to each other in a cross-sectional view is 95% or more.
4. The printed circuit board according to any one of claims 1 to 3, wherein: The average aspect ratio of the wiring portion is 1.2 or more and 5.0 or less.
5. The printed circuit board according to any one of claims 1 to 3, wherein: The average aspect ratio of the wiring portion is 1.4 or more and 4.0 or less.
6. The printed circuit board according to any one of claims 1 to 3, wherein: The average aspect ratio of the wiring portion is 1.6 or more and 3.0 or less.
7. The printed circuit board according to any one of claims 1 to 3, wherein: An average minimum distance between an outer surface of each of the wiring portions and an outer surface of the insulating layer is greater than 0 and is 20 μm or less.
8. The printed circuit board according to any one of claims 1 to 3, wherein: The insulating layer is a solder resist.
9. A method for manufacturing a printed circuit board, comprising: a stacking step of stacking a conductive pattern on at least one surface side of a base film, the base film having an insulating property, the conductive pattern including a plurality of wiring portions arranged adjacent to each other; a lamination step of laminating an insulating film on an outer surface of the base film and an outer surface of the conductive pattern; as well as a vacuum heat pressing step of vacuum heat pressing the stacked body on which the insulating film is laminated at a pressure of 0.3 MPa to 1.3 MPa and a heating temperature of 50° C. to 150° C., wherein, after the vacuum heat pressing step, the wiring portion has an average pitch of 1 μm to 20 μm and an average height of 30 μm to 120 μm, The ratio of the average height to the average pitch of the wiring portion is greater than or equal to 2.0 and less than or equal to 12.0, The average aspect ratio of the wiring portion is greater than 1.2, The average width of the wiring portion is 10 μm or more and 40 μm or less, and A filling area ratio of the insulating film between the wiring portions adjacent to each other in a cross-sectional view is 95% or more.
10. The method for manufacturing a printed circuit board according to claim 9, wherein: In the vacuum heat pressing step, the pressing time is 5 seconds to 20 seconds.
11. A printed circuit board, comprising: a base film, which has insulating properties; a conductive pattern stacked on at least one surface side of the base film and including a plurality of wiring portions arranged adjacent to each other; as well as an insulating layer covering an outer surface of the base film and an outer surface of the conductive pattern, wherein the wiring portion has an average pitch of 1 μm to 20 μm and an average height of 30 μm to 120 μm, The average aspect ratio of the wiring portion is greater than 1.2, The average width of the wiring portion is 10 μm or more and 40 μm or less, and The filling area ratio of the insulating layer between the wiring parts adjacent to each other in the cross-sectional view is 95% or more, Each of the wiring portions has, on a bottom surface portion on a base film side, a tapered portion in which a width of the wiring portion gradually decreases toward the base film.
12. The printed circuit board according to claim 11, wherein An average minimum distance between an outer surface of each of the wiring portions and an outer surface of the insulating layer is greater than 0 and is 20 μm or less.
13. The printed circuit board according to claim 11 or 12, wherein: The insulating layer is a solder resist.
14. A method for manufacturing a printed circuit board, comprising: a stacking step of stacking a conductive pattern on at least one surface side of a base film, the base film having an insulating property, the conductive pattern including a plurality of wiring portions arranged adjacent to each other; a lamination step of laminating an insulating film on an outer surface of the base film and an outer surface of the conductive pattern; as well as a vacuum heat pressing step of performing vacuum heat pressing on the stacked body on which the insulating film is laminated, wherein the wiring portion has an average pitch of 1 μm to 20 μm and an average height of 30 μm to 120 μm, The average aspect ratio of the wiring portion is greater than 1.2, The average width of the wiring portion is 10 μm or more and 40 μm or less, and The filling area ratio of the insulating film between the wiring portions adjacent to each other in the cross-sectional view is 95% or more, Each of the wiring portions has, on a bottom surface portion on a base film side, a tapered portion in which a width of the wiring portion gradually decreases toward the base film.
15. The method for manufacturing a printed circuit board according to claim 14, wherein: In the vacuum heat pressing step, the heating temperature is 50° C. or higher and 150° C. or lower, and the pressing time is 5 seconds or higher and 20 seconds or lower.