Printed circuit board

Abstract

To provide a printed circuit board which can be connected to an electronic component with a high-density fine circuit, and a print circuit board in which a structure realizing a fine circuit protrudes to the outermost side.SOLUTION: The printed circuit board includes: a first insulation layer 111; a first metal layer 120, of which part protrudes above the first insulation layer 111 and of which another part is buried in the first insulation layer 111; and a barrier layer 130 arranged on the first insulation layer 111. A barrier layer 130 contains an inorganic oxide film.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a printed circuit board.

Background Art

[0002] Recently, in order to meet the trend of weight reduction and miniaturization of mobile devices, there has been an increasing need to achieve thinner, lighter, shorter, and smaller printed circuit boards implemented thereon. Also, as the demand for high-performance printed circuit boards for servers increases, the demand for high-density circuits connecting logic semiconductors and memory semiconductors, or logic semiconductors and logic semiconductors, has also increased rapidly. Research continues to improve the reliability of connections with electronic components such as semiconductor chips having high-density fine circuits and the reliability of connections with the main board.

Summary of the Invention

Problems to be Solved by the Invention

[0003] One of several objects of the present invention is to provide a printed circuit board capable of making connections with electronic components having high-density fine circuits.

[0004] Another one of several objects of the present invention is to provide a printed circuit board in which the structure with fine circuits realized protrudes to the outermost side.

[0005] Another one of several objects of the present invention is to provide a printed circuit board capable of improving reliability.

Means for Solving the Problems

[0006] One of several solutions proposed through the present invention is to provide a printed circuit board including a first insulating layer, a first metal layer, a part of which protrudes on the first insulating layer and another part of which is embedded in the first insulating layer, and a barrier layer disposed on the first insulating layer, the barrier layer including an inorganic oxide film.

[0007] Another one of the several solutions proposed through the present invention is to provide a printed circuit board including a first insulating layer, a protruding portion protruding on the first insulating layer, an embedded portion embedded in the first insulating layer, and a protruding portion protruding in the outer peripheral surface direction, wherein the protruding portion, the embedded portion, and the protruding portion are integrally formed.

Advantages of the Invention

[0008] As one of the various advantages of the present invention, it is possible to provide a printed circuit board capable of connecting to an electronic component having a high-density fine circuit.

[0009] As another one of the various advantages of the present invention, it is possible to provide a printed circuit board in which a structure with a fine circuit is protruded on the outermost side.

[0010] As another one of the various advantages of the present invention, it is possible to provide a printed circuit board capable of improving reliability.

Brief Description of the Drawings

[0011]

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Embodiments for Carrying Out the Invention

[0012] Hereinafter, the present invention will be described with reference to the accompanying drawings. The shape and size of elements in the drawings can be exaggerated or reduced for clearer explanation.

[0013] Electronic device FIG. 1 is a block diagram schematically showing an example of an electronic device system.

[0014] Referring to the drawings, the electronic device 1000 houses a main board 1010. Chip-related components 1020, network-related components 1030, and other components 1040 are physically and / or electrically connected to the main board 1010. These are also coupled to other electronic components described later to form various signal lines 1090.

[0015] Examples of chip-related components 1020 include, but are not limited to, memory chips such as volatile memory (e.g., DRAM), non-volatile memory (e.g., ROM), and flash memory; application processor chips such as central processors (e.g., CPU), graphics processors (e.g., GPU), digital signal processors, encryption processors, microprocessors, and microcontrollers; and logic chips such as analog-to-digital converters and ASICs (application-specific ICs). Needless to say, other different forms of chip-related electronic components may also be included. Also, these chip-related components 1020 may be combined with each other. The chip-related components 1020 may be in a package form including the above-described chips and electronic components.

[0016] Examples of network-related components 1030 include, but are not limited to, Wi-Fi (such as the IEEE 802.11 family), WiMAX (such as the IEEE 802.16 family), IEEE 802.20, LTE (long term evolution), Ev-DO, HSPA+, HSDPA+, HSUPA+, EDGE, GSM, GPS, GPRS, CDMA, TDMA, DECT, Bluetooth, 3G, 4G, 5G, and any other wireless and wired protocols designated for future use. Needless to say, the network-related components 1030 may be combined with the chip-related components 1020.

[0017] Other components 1040 include high-frequency inductors, ferrite inductors, power inductors, ferrite beads, LTCC (Low Temperature Co-Firing Ceramics), EMI (Electro Magnetic Interference) filters, MLCC (Multi-Layer Ceramic Condensers), etc. However, it is not limited thereto, and other passive elements in the form of chip components used for other different applications may also be included. Needless to say, other components 1040 may be combined with chip-related components 1020 and / or network-related components 1030 with each other.

[0018] Depending on the type of the electronic device 1000, the electronic device 1000 may include other electronic components that are physically and / or electrically connected or not connected to the main board 1010. Examples of other electronic components include a camera module 1050, an antenna module 1060, a display 1070, a battery 1080, etc. However, it is not limited thereto, and it may be an audio codec, a video codec, a power amplifier, a compass, an accelerometer, a gyroscope, a speaker, a mass storage device (e.g., a hard disk drive), a CD (compact disk), a DVD (digital versatile disk), etc. Needless to say, other electronic components used for various applications depending on the type of the electronic device 1000 may also be included.

[0019] The electronic device 1000 may be, for example, a smart phone, a personal digital assistant, a digital video camera, a digital still camera, a network system, a computer, a monitor, a tablet, a laptop, a netbook, a television, a video game, a smart watch, an Automotive, or the like. However, it is not limited thereto, and needless to say, any other electronic device that processes data may be used.

[0020] FIG. 2 is a perspective view schematically showing an example of the electronic device.

[0021] Referring to the drawings, the electronic device may be, for example, a smart phone 1100. Inside the smart phone 1100, a motherboard 1110 is housed, and various components 1120 are physically and / or electrically connected to such a motherboard 1110. Also, other components that are or are not physically and / or electrically connected to the motherboard 1110, such as a camera module 1130 and / or a speaker 1140, are housed inside. A part of the components 1120 may be the above-described chip-related components, for example, a component package 1121, but is not limited thereto. The component package 1121 may be in the form of a printed circuit board on which electronic components including active components and / or passive components are surface-mounted. Alternatively, the component package 1121 may be in the form of a printed circuit board with active components and / or passive components built therein. On the other hand, the electronic device is not necessarily limited to the smart phone 1100, and needless to say, it may be other electronic devices as described above.

[0022] Printed circuit board FIG. 3 is a cross-sectional view schematically showing a printed circuit board according to an example.

[0023] Referring to FIG. 3, a printed circuit board according to an example includes a first insulating layer 111, a protruding portion 121 protruding on the first insulating layer 111, and a first metal layer 120 including an embedded portion 122 embedded in the first insulating layer 111, and includes a barrier layer 130 disposed on the first insulating layer 111, and the barrier layer 130 can include an inorganic oxide film. Further, a printed circuit board according to an example can have a protruding portion 123 where the first metal layer 120 protrudes in the outer peripheral surface direction.

[0024] The first insulating layer 111 can include an insulating material. Examples of the insulating material can include a thermosetting resin such as an epoxy resin, a thermoplastic resin such as a polyimide, or a material including an inorganic filler, an organic filler, and / or glass fiber (Glass Fiber, Glass Cloth, and / or Glass Fabric) together with such a resin. The insulating material may be a photosensitive material and / or a non-photosensitive material. For example, preferably, the insulating material of the first insulating layer 111 may be an insulating material of ABF (Ajinomoto Build-up Film), but is not limited thereto, and may include PPG (Prepreg), RCC (Resin Coated Copper), PID (Photo Imageable Dielectric), FR-4, BT (Bismaleimide Triazine), etc. However, it is not limited thereto, and other materials excellent in rigidity may be used as necessary.

[0025] A printed circuit board according to an example can have a so-called coreless structure, and the first insulating layer 111 can be disposed on the outermost side of the printed circuit board according to an example. More specifically, the first insulating layer 111 is disposed on the uppermost side of the printed circuit board, and the first metal layer 120 formed on the first insulating layer 111 can function as a post for connecting to an electronic component such as a semiconductor chip.

[0026] The first metal layer 120 can contain a metallic substance. As the metallic substance, copper (Cu), aluminum (Al), silver (Ag), tin (Sn), gold (Au), lead (Pb), titanium (Ti), or an alloy thereof can be used. The metallic substance can preferably contain copper (Cu), but is not limited thereto. The first metal layer 120 can be an area for mounting electronic components and semiconductor chips, etc., can be an area for connection with a main board, etc., or can be connected to a circuit pattern for signal connection with other pads. The first metal layer 120 can contain a plurality of metal posts, and is not limited thereto, and can further contain a plurality of patterns and / or pads. The metal posts or patterns / pads of the first metal layer 120 can perform various functions according to the design. For example, it can contain a ground pattern / pad, a power pattern / pad, a signal pattern / pad, etc. Here, the signal pattern / pad can contain a pattern / pad for electrical connection of various signals excluding ground, power, etc., for example, a data signal. Also, the patterns / pads of the first metal layer 120 can electrically transmit and receive signals with different patterns / pads from each other, and can also perform functions by being electrically short-circuited with other patterns / pads.

[0027] In the first metal layer 120, when a high-density fine pitch is required for mounting electronic components such as semiconductor chips, the interval between the respective metal posts and / or patterns of the first metal layer 120 can be narrowed. When it is for mounting electronic components such as passive components, the interval of the first metal layer 120 can be made wider, and the height of the first metal layer 120 can also be formed lower.

[0028] The first metal layer 120 may be formed by any one of SAM (Semi Additive Process), MSAP (Modified Semi Additive Process), TT (Tenting), or Subtractive process, but is not limited thereto. As a non-limiting example, the first metal layer 120 can be formed by performing electroless copper plating (chemical copper) followed by electroplating (electrolytic copper), and the first metal layer 120 can also be formed by firing a paste containing a metal substance. The method of forming the first metal layer 120 is not limited thereto, and can further include configurations or methods available to those with ordinary knowledge in the technical field. As a non-limiting example, the first metal layer 120 can include a seed layer 125 and a plating layer 126, respectively.

[0029] The seed layer 125 is disposed on the outermost side of the first metal layer 120 and can be disposed along the upper side and the side surface of the first metal layer 120. This can be the result of forming the seed layer 125 along the wall surfaces of the temporary layer and the through holes formed in the first insulating layer 111. The seed layer 125 can function as a seed for forming the plating layer 126. The seed layer 125 can include an electroless plating layer (or chemical copper) formed by electroless plating, but is not limited thereto, and may include a sputtering layer formed by sputtering instead of electroless plating, or may include both an electroless plating layer and a sputtering layer. Without being limited thereto, if necessary, a copper foil may be included, and any metal that can function as a seed for electroplating can be used without limitation.

[0030] The plating layer 126 is disposed on the seed layer 125 and can be formed using the seed layer 125 as a plating seed. The plating layer 126 can be formed to fill the temporary layer and the through holes formed in the first insulating layer 111. Since it is formed on the seed layer 125 formed on the inner wall of the through hole, the plating layer 126 is disposed on the seed layer 125, but can be formed in the inner or lower direction of the printed circuit board. The plating layer 126 can include an electrolytic plating layer (or electrolytic copper) formed by electrolytic plating. However, it is not limited thereto, and the plating layer 126 may be formed by baking a paste containing a metal substance, and does not necessarily have to be formed by plating. That is, the plating layer 126 is for expressing that it is a separate metal layer distinguishable from the seed layer 125, and the method of forming this is not necessarily limited by the text itself, and those having ordinary knowledge in the technical field can further include available configurations or methods.

[0031] The first metal layer 120 can function as a means for connecting the printed circuit board to an electronic component such as a semiconductor chip or to another component such as a main board. In particular, since the first metal layer 120 includes a protruding portion 121 protruding above the first insulating layer 111, connection with an electronic component having a fine pitch can be performed more smoothly, and defects due to short circuits or disconnections of connection members during the formation of the electrical connection path can be prevented. In the printed circuit board according to an example, after forming through holes through the first insulating layer 111, the barrier layer 130, and the temporary layer, the first metal layer 120 is formed to fill the through holes, and the protruding portion 121 of the first metal layer 120 is formed by removing the temporary layer. Therefore, the protruding portion of the first metal layer 120 can have a certain height.

[0032] The printed circuit board according to one example is a so-called coreless substrate, and a part of the first metal layer 120 disposed on the uppermost side of the substrate may be embedded in the first insulating layer 111. However, since the temporary layer and the barrier layer 130 are formed first at the stage of forming the first metal layer 120 and then the first insulating layer 111 is formed, the printed circuit board according to one example can have a structure in which the protruding portion 121 of the first metal layer 120 protrudes more than the first insulating layer 111 even though it is a coreless substrate.

[0033] The first metal layer 120 can include an embedded portion 122 embedded in the first insulating layer 111 together with a protruding portion 121 protruding above the first insulating layer 111. The embedded portion 122 is a portion that penetrates the upper and lower surfaces of the first insulating layer 111 and corresponds to a region disposed within the first insulating layer 111. The side surface of the embedded portion 122 can be covered by the first insulating layer 111.

[0034] On the other hand, the first metal layer 120 can include a protruding portion 123 together with the protruding portion 121 and the embedded portion 122. The protruding portion 123 can correspond to a plating foot of the first metal layer 120 protruding in the outer peripheral surface direction of the first metal layer 120. The protruding portion 123 can be formed across the protruding portion 121 and the embedded portion 122 of the first metal layer 120. The lower side of the protruding portion 123 can be in contact with the first insulating layer 111, the upper side of the protruding portion 123 is not covered by the first insulating layer 111, and can be exposed by the first insulating layer 111. A part of the protruding portion 123 can be disposed within the first insulating layer 111, and another part can have a structure protruding more than the first insulating layer 111.

[0035] The protrusion 123 may be the result of the first metal layer 120 filling a groove formed by removing a part of the barrier layer 130. After forming a through hole that penetrates the dummy layer, the barrier layer 130, and the first insulating layer 111, when removing a part of the barrier layer 130 exposed on the inner wall of the through hole, a groove may be formed in which a part of the dummy layer located above the barrier layer 130 and a part of the first insulating layer 111 located below the barrier layer 130 are removed, and it may be the result of the first metal layer 120 being formed such that the groove is filled in the step of forming the first metal layer 120.

[0036] In the printed circuit board according to an example, since the protrusion 123 is included in the first metal layer 120, the area where the first metal layer 120 contacts the first insulating layer 111 can be widened, and the protrusion 123 is disposed on the upper surface of the first insulating layer 111 to generate an anchoring effect, etc., so that the adhesion and bonding force between the first metal layer 120 and the first insulating layer 111 can be enhanced. Since the first metal layer 120 connected to an electronic component such as a semiconductor chip can be stably bonded to the first insulating layer 111, the printed circuit board according to an example can improve the connection reliability.

[0037] The protruding portion 123 may have an annular shape so as to correspond to the shape of the first metal layer 120, but is not necessarily limited thereto. As an example of not being limited, the width of the protruding portion 123 in the central portion may be wider than the width in the upper side and / or the lower side. The width of the protruding portion can be measured by photographing a cross-section cut in the stacking direction of the printed circuit board with a scanning microscope or the like. That the width of the protruding portion 123 in the central portion may be wider than the width in the upper side and / or the lower side means that the central region may have a convex shape rather than the upper and lower sides in the cross-section of the printed circuit board. In FIG. 3, the protruding portion 123 is shown as having a trapezoidal shape, but is not limited thereto, and the protruding portion 123 may have a curved surface or a surface with irregularities. Further, the shape of the protruding portion 123 is not limited to that shown in FIG. 3, and may not be vertically symmetric with respect to the surface on which the barrier layer 130 is formed. This is because the degree of removal of the temporary layer and the degree of removal of the first insulating layer 111 may be different at the stage where the groove is formed.

[0038] The seed layer 125 of the first metal layer 120 can extend along the outside of the protruding portion 123. That is, the seed layer 125 can be disposed outside the first metal layer 120 and can be disposed so as to extend along the protruding portion 121, the protruding portion 123, and the embedded portion 122. The seed layer 125 is disposed along the inner walls of the through holes and the grooves, and since the plating layer 126 is formed on the seed layer 125, the seed layer 125 can be disposed on the outermost side of the first metal layer 120. At this time, since the thickness of the seed layer 125 may be smaller than the thickness of the groove, the seed layer 125 can be conformally disposed along the boundary of the first insulating layer 111 and the boundary of the temporary layer so as to follow the inside of the groove.

[0039] On the one hand, the protrusion 121, the embedded portion 122, and the protrusion 123 of the first metal layer 120 are not distinct in terms of their boundaries, but rather are concepts for distinction based on position and shape. The first metal layer 120 is integrally formed, and there may be cases where the boundaries between the protrusion 121, the embedded portion 122, and the protrusion 123 are unclear. That is, the seed layer 125 disposed outside the protrusion 121 extends along the outside of the protrusion 123 and extends outside the embedded portion 122, and the seed layers 125 disposed in each region can be integrally formed. Also, the plating layer 126 disposed on the protrusion 121 can also extend to the protrusion 123 and the embedded portion 122, and the plating layers 126 disposed in each region can be integrally formed.

[0040] The first metal layer 120 can have an upward taper shape, and each of the protrusion 121 and the embedded portion 122 can have an upward taper shape. For the first metal layer 120 to have an upward taper shape means that it can have a substantially tapered shape such that the width of the upper surface of the protrusion 121 of the first metal layer 120 is narrower than the width of the lower surface of the embedded portion 122 of the first metal layer 120. Since the first metal layer 120 is formed to fill a through-hole penetrating the dummy layer and the first insulating layer 111, the first metal layer 120 can have the same shape as the through-hole. Since the step of forming the through-hole by penetrating the dummy layer and the first insulating layer 111 is performed from the lower side to the upper side, the upper width, which is the bottom surface of the through-hole, can be formed to be narrower than the lower width, which is the opening, and can have a tapered shape. However, it is not necessarily limited to this, and the first metal layer 120 may have a shape without a taper, with the width of the lower surface and the width of the upper surface being substantially the same.

[0041] That is, the first metal layer 120 can have an upward taper shape, and at this time, the protrusion 121 and the embedded portion 122 can have a taper shape in substantially the same direction as each other. The printed circuit board according to an example has a coreless structure, and since the first metal layer 120 is formed to fill a through-hole penetrating the dummy layer and the first insulating layer 111, the first metal layer 120 can have an upward taper shape.

[0042] The barrier layer 130 is disposed above the first insulating layer 111 and can be used as a means for separating the temporary layer from the first insulating layer 111 as will be described later in the manufacturing method. After forming the temporary layer, since the barrier layer 130 is formed to form the first insulating layer 111, it can have a form in which a release layer is formed between the temporary layer and the first insulating layer 111. By removing the temporary layer disposed above the barrier layer 130, the protrusion 121 of the first metal layer 120 can be formed. At this time, even if the temporary layer and the first insulating layer 111 contain substantially the same insulating material, since the barrier layer 130 is disposed between the temporary layer and the first insulating layer 111, it is possible to prevent the first insulating layer 111 from being damaged in the step of removing the temporary layer.

[0043] The barrier layer 130 can contain a material substantially different from that of the first insulating layer 111. The barrier layer 130 may be a thin oxide film containing a metal oxide. As the metal oxide, it can contain at least one substance among Al2O3, SiO2, TiO2, ZnO, ZrO2, HfO2, La2O3, but can also contain a doped metal oxide with a different metal element. The metal oxide can preferably contain alumina (Al2O3). On the other hand, the material of the barrier layer 130 is not necessarily limited to a metal oxide, and can also contain a metal substance with low reactivity such as Pt and Ru.

[0044] The barrier layer 130 can be formed using a thin film deposition method, such as an ALD (Atomic Layer Deposition) method, an MVD (Molecular Vapor Deposition) method, etc. By forming the barrier layer 130 using a thin film deposition method, the barrier layer 130 can include a thinner oxide film compared to the first insulating layer 111. As a non-limiting example, the barrier layer 130 can include a thin oxide film with a thickness of less than 0.1 μm, preferably about 0.001 μm to 0.05 μm. The barrier layer 130 may be thinner than the first insulating layer 111 and may be formed thinner than the seed layer 125. On the other hand, in FIG. 3, the barrier layer 130 is shown as having the same thickness as the seed layer 125, but it is not limited thereto, and the seed layer 125 may be formed thicker than the barrier layer 130. As a non-limiting example, the seed layer 125 can include an electroplated layer with a thickness of less than 1 μm, preferably about 0.1 μm to 0.5 μm.

[0045] The thickness of the barrier layer 130 can be measured by photographing a cross-sectional cut in the stacking direction of the printed circuit board with a scanning microscope or the like. For example, the thickness of the barrier layer 130 can be the average value of the vertical distances of the barrier layer 130 measured at any five points. Such a measurement method can also be applied to the thickness measurement method of the seed layer 125. Since the seed layer 125 can be conformally disposed along the outer surface of the first metal layer 120, the thickness of the seed layer 125 can be interpreted as the distance across the outer and inner surfaces of the seed layer 125, but it can include measurement errors or errors in the manufacturing process.

[0046] By being formed using a thin film deposition method, the barrier layer 130 can be disposed along the upper surface of the first insulating layer 111. More specifically, since the first insulating layer 111 is formed after forming the barrier layer 130 on the temporary layer, after the barrier layer 130 is formed along the temporary layer, the first insulating layer 111 is laminated.

[0047] The barrier layer 130 can be in contact with the side portion of the first metal layer 120. Specifically, the barrier layer 130 can be in contact with the protrusion of the first metal layer 120. This can be the result of the protrusion 123 being formed to fill a groove that is an area where a part of the barrier layer 130 and the first insulating layer 111 have been removed.

[0048] In order to form protrusions on a conventional coreless substrate, a step of further forming a separate metal layer on the outermost embedded pattern of the coreless substrate or a step of removing a part of the outermost insulating layer was performed. However, in the printed circuit board according to an example, since the barrier layer 130 is disposed on the first insulating layer 111, the protrusion 121 and the embedded portion 122 of the first metal layer 120 can be integrally formed, and the first insulating layer 111 can be protected by the barrier layer 130.

[0049] Therefore, the printed circuit board according to the first embodiment can overcome the alignment problem of protrusions having a fine pitch and can minimize defects generated at the interface between two metal layers and undercut defects. Also, since a step of removing a part of the first insulating layer 111 is not required, the first insulating layer 111 can be protected at the step of removing the temporary layer. As a result, defects such as a crevice not occurring between the first metal layer 120 and the first insulating layer 111 can be prevented, and defects occurring in the protruding relationship between the outermost insulating layer and the first metal layer 120 can be avoided.

[0050] That is, it is a structural feature that occurs because the protrusion can be formed by a single plating, different from the conventional method of performing multiple platings to have a protruding structure while having a coreless structure. By having such a structure, problems such as alignment and detachment occurring between the protrusion and the embedded portion do not occur.

[0051] Moreover, unlike the conventional method of removing a part of the insulating layer so as to have a protruding structure while having a coreless structure, after forming through-holes and grooves in the insulating layer, a metal layer is formed by a single plating so as to fill these, and it is a structural feature that occurs because the upper temporary layer can be easily removed with the barrier layer 130 as a boundary. By having such a structure, problems such as crevice, depression, or crack do not occur near the boundary between the metal layer and the insulating layer.

[0052] A printed circuit board according to an example may further include a second insulating layer 112 disposed below the first insulating layer 111, a first wiring layer 151 disposed on the second insulating layer 112, and a first via layer 155 that penetrates at least a part of the second insulating layer 112 so as to connect the first wiring layer 151 and the first metal layer 120 or to connect the first wiring layers 151 to each other.

[0053] The second insulating layer 112 can include an insulating material. As the insulating material, a thermosetting resin such as an epoxy resin, a thermoplastic resin such as polyimide, or a material including an inorganic filler, an organic filler, and / or glass fiber (Glass Fiber, Glass Cloth, and / or Glass Fabric) together with such a resin can be included. The insulating material may be a photosensitive material and / or a non-photosensitive material. For example, as the insulating material of the second insulating layer 112, it may be an insulating material of ABF (Ajinomoto Build-up Film), but is not limited thereto, and may also include PPG (Prepreg), RCC (Resin Coated Copper), PID (Photo Imageable Dielectric), FR-4, BT (Bismaleimide Triazine), etc. However, it is not limited thereto, and other materials excellent in rigidity may be used as necessary. The second insulating layer 112 can include substantially the same type of insulating material as the first insulating layer 111. That is, it means that the first insulating layer 111 may be a build-up insulating layer like the second insulating layer 112.

[0054] The thickness of the first insulating layer 111 may be formed thinner than the thickness of the second insulating layer 112. Since the first metal layer 120 must be able to make fine connections, it is advantageous for the first metal layer 120 to include thin and fine pads and posts. Therefore, in order to penetrate the upper and lower surfaces of the first insulating layer 111, the thickness of the first insulating layer 111 may be realized thinner than that of the second insulating layer 112 which is a general build-up layer. On the other hand, the thickness relationship between the first insulating layer 111 and the second insulating layer 112 is not necessarily limited to this, and the thickness of the first insulating layer 111 and the thickness of the second insulating layer 112 can be variously designed as required. The thickness of the insulating layer can be measured by photographing a cross-sectional cut in the stacking direction of the printed circuit board with a scanning microscope or the like, and can be the average value of the vertical distances measured at any five points, but it is not necessarily limited to this, and as long as the thickness measurement method of the first insulating layer 111 and the thickness measurement method of the second insulating layer 112 can be made the same to compare the thicknesses with each other.

[0055] On the other hand, the second insulating layer 112 can be composed of a plurality of insulating layers, and those skilled in the art can apply available configurations for the number of layers and the thickness.

[0056] The first wiring layer 151 can contain a metallic substance. As the metallic substance, copper (Cu), aluminum (Al), silver (Ag), tin (Sn), gold (Au), lead (Pb), titanium (Ti), or an alloy thereof can be used. The metallic substance can preferably contain copper (Cu), but is not limited thereto. The first wiring layer 151 can respectively contain an electroless plating layer (or chemical copper) and an electrolytic plating layer (or electrolytic copper), but is not limited thereto. A sputtering layer may be formed instead of the electroless plating layer, or both may be included. Further, a copper foil can be included.

[0057] The first wiring layer 151 can include a plurality of pads / patterns, each of which can perform various functions according to the design. For example, it can include a ground pad / pattern, a power pad / pattern, a signal pad / pattern, etc. Here, the signal pad / pattern can include pads / patterns for electrical connection of various signals excluding ground, power, etc., such as data signals.

[0058] As a non-limiting example, the first wiring layer 151 can include a first pad 152 and a first pattern 153. The first pad 152 can be configured to be connected to the first via layer 155, and the first pattern 153 can be a wiring connecting the first pads 152 to each other, but is not limited thereto and can also be patterns of various shapes.

[0059] The width of the first pad 152 of the first wiring layer 151 may be wider than the distance between both ends of the protrusion 123 of the first metal layer 120. That is, the width between both ends of the protrusion 123 of the first metal layer 120 may be narrower than the width of the first pad 152 of the first wiring layer 151. The width of the first pad 152 and the width between both ends of the protrusion 123 of the first metal layer 120 can be measured by photographing a cross-section in the stacking direction of the printed circuit board with a scanning microscope or the like. The first wiring layer 151 is configured to be disposed inside the printed circuit board as a build-up wiring layer, while the first metal layer 120 is disposed on the outermost side of the printed circuit board and connected to electronic components such as semiconductor chips. Therefore, the first metal layer 120 can be realized more finely than the first wiring layer 151. In particular, since the width between both ends of the protrusion 123 of the first metal layer 120 can correspond to the longest width of the first metal layer 120, when the width of the first metal layer 120 is larger than the width of the first pad 152, it is not only disadvantageous in the connection with electronic components having a fine structure, but also the possibility of a short circuit defect due to solder or the like increases. Therefore, forming the width between both ends of the protrusion 123 of the first metal layer 120 smaller than the first pad 152 of the first wiring layer 151 can be more advantageous in connection reliability.

[0060] The first via layer 155 can each include micro vias. The micro vias may be filled vias that fill via holes, or may be conformal vias arranged along the wall surfaces of the via holes. The micro vias can be arranged in a stacked type and / or a staggered type. The first via layer 155 can each include a metal, and the metal can include copper (Cu), aluminum (Al), silver (Ag), tin (Sn), gold (Au), nickel (Ni), lead (Pb), titanium (Ti), or alloys thereof, etc., and preferably can include copper (Cu), but is not limited thereto. The first via layer 155 can each include an electroless plating layer (or electroless copper) and an electroplating layer (or electrolytic copper), but is not limited thereto. A sputtering layer may be formed instead of the electroless plating layer, or both may be included. The first via layer 155 can each perform various functions according to the design of the layer. For example, it can include ground vias, power vias, signal vias, etc.

[0061] On the other hand, since the number of layers of the second insulating layer 112 can be diverse, the first wiring layer 151 arranged on the second insulating layer 112 and the first via layer 155 penetrating at least a part of the second insulating layer 112 can also have various numbers of layers.

[0062] In addition, the printed circuit board according to an example can further include a solder resist layer 160 disposed below the second insulating layer 112. That is, the printed circuit board according to an example can further include the solder resist layer 160 at the lowermost side. The solder resist layer 160 can include an insulating material and can include a liquid or film-type solder resist, but is not limited thereto, and other types of insulating materials may be used. The solder resist layer 160 can have an opening that exposes at least a part of the first wiring layer 151. A part of the first wiring layer 151 exposed through the opening can function as a pad for connection to other components such as a main board, but is not necessarily limited thereto.

[0063] The printed circuit board according to an example can further include a surface treatment layer 140 disposed on the first metal layer 120. The surface treatment layer 140 is disposed on the first metal layer 120 and can cover the region of the first metal layer 120 exposed from the first insulating layer 111. That is, the surface treatment layer 140 can cover the protruding portion 121 of the first metal layer 120 and can cover the upper portion of the protruding portion 123.

[0064] The surface treatment layer 140 can contain any one of nickel (Ni), palladium (Pd), and gold (Au), and a plurality of these metal layers can also be realized. For example, the surface treatment layer 140 may be at least a part of an ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold) structure or at least a part of an ENIG (Electroless Nickel Immersion Gold) structure. The surface treatment layer 140 is not limited to this and can also include an OSP (Organic Solder Passivation) structure containing organic substances. The surface treatment layer 140 can improve the adhesion and signal transmission force between the first metal layer 120 and connection means such as solder. In FIG. 3, the surface treatment layer 140 is shown as being composed of one layer, but it is not limited to this, and the surface treatment layer 140 may be realized by a plurality of metal layers as described above.

[0065] The thickness of the surface treatment layer 140 may be greater than the thickness of the barrier layer 130. As described above, the barrier layer 130 may be an oxide film formed by surface vapor deposition. However, since the surface treatment layer 140 is an electroless plating layer and can include a plurality of metal layers, the surface treatment layer 140 may be thicker than the barrier layer 130 including a thin oxide film.

[0066] On the other hand, the printed circuit board according to an example is not limited to the configuration shown in FIG. 3, and other configurations may be further included or may be omitted depending on the case. That is, it can further include configurations that can be used by those having ordinary knowledge in the technical field.

[0067] FIG. 4 is a cross-sectional view schematically showing a printed circuit board according to another example.

[0068] Referring to FIG. 4, in a printed circuit board according to another example, the protrusion 123 of the first metal layer 120 can have a shape with rounded ends. This may be the result of the etching solution penetrating more widely at the stage of removing a part of the barrier layer 130 and the first insulating layer 111 to form a groove. Since the ends of the protrusion 123 have a rounded shape, the area of the first metal layer 120 of the printed circuit board according to another example in contact with the first insulating layer 111 can be increased.

[0069] On the other hand, among the configurations other than the content related to the shape of the first metal layer 120, the same configurations as those of the printed circuit board according to other embodiments can also be applied to the printed circuit board according to another example. Therefore, duplicate descriptions regarding this are omitted.

[0070] Manufacturing method of printed circuit board FIGS. 5 to 15 are cross-sectional views schematically showing a manufacturing method of a printed circuit board according to an example.

[0071] A manufacturing method of a printed circuit board according to an example can include steps of forming a temporary layer T on a carrier substrate C, forming a barrier layer 130 on the temporary layer T, forming a first insulating layer 111 on the barrier layer 130, forming a through hole h penetrating the first insulating layer 111, the barrier layer 130, and the temporary layer T, removing a part of the barrier layer 130, the first insulating layer 111, and the temporary layer T to form a groove g, forming a first metal layer 120 so as to fill the through hole h and the groove g, and removing the carrier substrate C and the temporary layer T.

[0072] Since the manufacturing method of the printed circuit board according to an example forms the first insulating layer 111 after forming the barrier layer 130 on the temporary layer T, damage to the first insulating layer 111 can be prevented at the stage of removing the temporary layer T. In particular, even if the temporary layer T and the first insulating layer 111 contain substantially the same insulating material, damage to the first insulating layer 111 can be prevented at the stage of removing the temporary layer T. Also, since the first metal layer 120 is formed after forming the through hole h and the groove g, the protruding portion 121, the embedded portion 122, and the protruding portion 123 of the first metal layer 120 can be integrally formed.

[0073] Referring to FIG. 5, the method for manufacturing a printed circuit board may include a step of forming a temporary layer T on a carrier substrate C. Further, before the step of forming the temporary layer T on the carrier substrate C, a step of forming a stopper layer S on the carrier substrate C may be further included. In this case, the temporary layer T can be disposed on the stopper layer S.

[0074] The carrier substrate C is for supporting when forming an insulating layer, a wiring layer, etc., and can be formed of an insulating material or a metallic material. In FIG. 5, the carrier substrate C is shown as including a core C1 and seeds C2 formed on both surfaces of the core C1, but it is not limited thereto. The carrier substrate C may be a single-layer carrier substrate C, or the seeds C2 may be double-layered. That is, the carrier substrate C is an example of one case, and the carrier substrate C can be used by those having ordinary knowledge in the technical field, is used as a support substrate, and can be detached or removed later, and can be used without particular limitation in the present invention as long as it can be detached or removed later.

[0075] Before the step of forming the temporary layer T, a step of forming a stopper layer S on the carrier substrate C may be further included. The stopper layer S can then perform a function of separating the carrier substrate C and the first metal layer 120. The stopper layer S can contain a metallic substance, and as the metallic substance, nickel (Ni), aluminum (Al), tin (Sn), gold (Au), lead (Pb), titanium (Ti), or an alloy thereof, etc. can be used. The stopper layer S preferably can contain nickel (Ni), but is not limited thereto. Since the stopper layer S needs to be separated from the temporary layer T and the first metal layer 120 in a later detachment step, the stopper layer S may be a different metal material from the temporary layer T, and can be used without particular limitation as long as it is a substance that easily separates the first metal layer 120 and the carrier substrate C in the step of removing the carrier substrate C.

[0076] The temporary layer T is a temporary structure for forming the protruding portion 121 of the first metal layer 120, and may be a temporary structure that is disposed on the carrier substrate C and removed after forming the first metal layer 120.

[0077] The temporary layer T can contain an insulating material. As the insulating material, a thermosetting resin such as an epoxy resin, a thermoplastic resin such as polyimide, or a material containing an inorganic filler, an organic filler, and / or glass fiber (Glass Fiber, Glass Cloth, and / or Glass Fabric) together with such a resin can be included. The insulating material may be a photosensitive material and / or a non-photosensitive material. For example, as the insulating material of the second insulating layer 112, it may be an insulating material of ABF (Ajinomoto Build-up Film), but is not limited thereto, and may include PPG (Prepreg), RCC (Resin Coated Copper), PID (Photo Imageable Dielectric), FR-4, BT (Bismaleimide Triazine), etc. However, it is not limited thereto, and other materials with excellent rigidity may be used as necessary. The temporary layer T can contain substantially the same type of insulating material as the first insulating layer 111. Even if the temporary layer T contains substantially the same type of insulating material as the first insulating layer 111, since the barrier layer 130 is formed in a later stage, the temporary layer T can be easily separated from the first insulating layer 111, and damage to the first insulating layer 111 can be prevented.

[0078] On the other hand, without being limited thereto, the temporary layer T can also contain a metallic substance without containing an insulating material. In this case, the temporary layer T contains a substance different from the metallic substance of the first metal layer 120, and the first metal layer 120 may not react during the removal stage of the temporary layer T.

[0079] Referring to FIG. 6, the method for manufacturing a printed circuit board can include a step of forming a barrier layer 130 on the temporary layer T.

[0080] The barrier layer 130 can be formed using a thin film deposition method, for example, an ALD (Atomic Layer Deposition), MVD (Molecular Vapor Deposition) method, etc. Since the barrier layer 130 is formed by a thin film deposition method, the barrier layer 130 can include a thinner oxide film compared to the temporary layer T and the first insulating layer 111. Since the method of forming the barrier layer 130 can be performed by a deposition method, the barrier layer 130 can be thinly formed along the lower surface of the temporary layer T.

[0081] Since the barrier layer 130 includes a material different from that of the temporary layer T and the first insulating layer 111, after the step of forming the first metal layer 120, the temporary layer T can be removed more smoothly while protecting the first insulating layer 111 in the step of removing the temporary layer T.

[0082] Referring to FIG. 7, the method of manufacturing a printed circuit board can include a step of forming the first insulating layer 111 on the barrier layer 130.

[0083] The description of the first insulating layer 111 is as described above for the printed circuit board, and the method of forming the first insulating layer 111 can be used without limitation as long as it is a known method of forming an insulating layer available to those having ordinary knowledge in the art.

[0084] Referring to FIG. 8, the method of manufacturing a printed circuit board can include a step of forming a through hole h that penetrates the first insulating layer 111, the barrier layer 130, and the temporary layer T. The method of forming the through hole h can be used without limitation as long as it is a method of processing so as to penetrate the first insulating layer 111 and the temporary layer T. As a non-limiting example, it can be performed by laser drilling, mechanical drilling, etc., but is not limited thereto, and any method that can penetrate the insulating layer can be used without limitation. On the other hand, when using laser drilling, a CO2 laser or a YAG laser can be used, but is not limited thereto.

[0085] At this time, the through hole h can be formed by a single process, but it is not limited thereto. After penetrating the first insulating layer 111, after removing a part of the barrier layer, the through hole h can also be formed by a method of penetrating the temporary layer T. Since the through hole h penetrates the temporary layer T, the barrier layer 130, and the first insulating layer 111, the stopper layer S can be exposed through the through hole h. Since the through hole h can be processed from the lower side to the upper side with reference to FIG. 8, the through hole h can have an upward tapered shape. On the other hand, the degree of taper of the through hole h can be determined by the processing method and conditions.

[0086] Referring to FIG. 9, the method of manufacturing a printed circuit board can include a step of forming a groove g. The step of forming the groove can be performed by removing a part of the barrier layer 130 exposed by the through hole h, and removing a part of the first insulating layer 111 adjacent to the barrier layer 130 and a part of the temporary layer T.

[0087] The groove g may be an area for forming the protrusion 123 of the first metal layer 120. Based on the through hole h, a part of the barrier layer 130, the first insulating layer 111, and the temporary layer T can be removed in the horizontal direction or the direction of the outer peripheral surface of the through hole h. The method of forming the groove g can be utilized without limitation as long as it can remove a part of the insulating material. As a non-limiting example, the step of processing the groove can include the step of removing a part of the barrier layer 130 and the step of performing desemear. The step of removing a part of the barrier layer 130 can be performed by etching, and desemear is a method of removing residues generated in the step of forming the through hole h and can be performed by wet desemear. After the step of removing a part of the barrier layer 130, since a wet process can be performed in the step of removing a part of the first insulating layer 111 and the temporary layer T, the solution can be concentrated in the area where a part of the barrier layer 130 has been removed, whereby the groove g can be formed. By forming the groove g, the area where the first metal layer 120 contacts the first insulating layer 111 becomes wider, and the adhesion of the first metal layer 120 can be improved. In addition, since a part of the barrier layer 130 has been removed, the adhesion between the temporary layer T and the barrier layer 130 may decrease compared to before the groove g is formed. Therefore, in subsequent steps, the separation of the barrier layer 130 and the temporary layer T becomes easier, and the formation of the protrusion 121 of the first metal layer 120 can be facilitated.

[0088] In FIG. 10, in the vertical cross-sectional view of the printed circuit board, the shape of the groove g is shown as triangular or trapezoidal, but it is not limited thereto, and the shape of the groove g can be various according to the degree of penetration of the solution. For example, it may have a curved surface, and it goes without saying that the upper and lower sides of the groove g may have an asymmetric structure.

[0089] Referring to FIG. 10, the manufacturing method of the printed circuit board can include the step of forming the first metal layer 120. The step of forming the first metal layer 120 can include the step of forming the seed layer 125 along the through hole h and the groove g.

[0090] The seed layer 125 can be formed inside the through holes h and the grooves g and arranged along the lower surface of the first insulating layer 111. That is, the seed layer 125 may be conformally formed along the through holes h and the grooves g. The seed layer 125 can constitute the outermost side of the first metal layer 120. The step of forming the seed layer 125 may be performed by electroless plating, but is not limited thereto, and may be performed by sputtering. On the other hand, the step of forming the seed layer 125 is not limited thereto, and any method for forming the seed layer 125 for electrolytic plating can be used without limitation.

[0091] Referring to FIG. 11, the method for manufacturing a printed circuit board may include a step of forming a first metal layer 120. The step of forming the first metal layer 120 may include a step of forming a plating layer 126 on the seed layer 125.

[0092] The plating layer 126 is arranged on the seed layer 125 and can be formed using the seed layer 125 as a plating seed. The plating layer 126 can be formed to fill the through holes h and the grooves g and can also be formed on the lower side of the first insulating layer 111. The formation of the plating layer 126 can be performed by electrolytic plating, and any method for forming the plating layer 126 available to those with ordinary knowledge in the art can be used without particular limitation.

[0093] Referring to FIG. 12, the method for manufacturing a printed circuit board may include a step of forming a first metal layer 120. The step of forming the first metal layer 120 may include a step of removing a part of the seed layer 125 and the plating layer 126 to complete the first metal layer 120.

[0094] Since the seed layer 125 functions as a plating lead-in line for the plating layer 126, it is formed over the entire lower surface of the first insulating layer 111. The plating layer 126 is disposed on the seed layer 125, fills both the first through hole h1 and the second through hole h2, and can also be formed on the lower side of the first insulating layer 111. Therefore, there is a possibility that the seed layer 125 and the plating layer 126 cannot perform their respective functions while being electrically connected to each other. Thus, by removing a part of the seed layer 125 and the plating layer 126, the respective first metal layers 120 can perform independent functions. At this time, the step of removing a part of the first metal layer 120 can be performed by etching, but is not limited thereto.

[0095] On the other hand, referring to FIGS. 10 to 12, it is shown that after forming the seed layer 125 by electroless plating, the plating layer 126 is formed by electroplating to form the first metal layer 120. However, it is not necessarily limited thereto. The method of forming the first metal layer 120 is not limited to this, and the first metal layer 120 may be formed so as to fill the through hole h and the groove g. Any method of forming a metal layer available to those with ordinary knowledge in the technical field can be used without particular limitation.

[0096] Referring to FIG. 13, the method of manufacturing a printed circuit board may include forming a second insulating layer 112 on the lower surface of the first insulating layer 111, forming a first wiring layer 151 on the second insulating layer 112, and connecting the first metal layer 120 and the first wiring layer 151 to each other, or forming a first via layer 155 that penetrates at least a part of the second insulating layer 112 so as to connect the first wiring layers 151 to each other. Further, it may further include forming a solder resist layer 160 on the second insulating layer 112.

[0097] The method of forming the second insulating layer 112, the method of forming the first wiring layer 151 and the first via layer 155, and the method of forming the solder resist layer 160 can be used without limitation as long as they are build-up methods of insulating layers and wiring layers available to those with ordinary knowledge in the technical field.

[0098] Referring to FIG. 14, the method for manufacturing a printed circuit board may include a step of removing the carrier substrate C, a step of removing the stopper layer S, and a step of removing the temporary layer T.

[0099] The step of removing the carrier substrate C can apply various methods according to the form of the carrier substrate C. For example, in the step of removing the carrier substrate C, after removing the core contained in the carrier substrate, the copper foil may be sequentially removed, or the carrier substrate may be removed integrally, that is, the core and the copper foil may be removed simultaneously. The step of removing the carrier substrate C can be performed by unrestrictedly using the processes used in known carrier detachment.

[0100] The step of removing the stopper layer S can be performed by etching, but is not limited thereto. The step of removing the stopper layer S can be performed by different processes according to the constituent material of the stopper layer S, and any process that can remove the constituent material of the stopper layer S can be used without restriction. That is, different conditions can be realized according to the material of the stopper layer S. Since the stopper layer S contains a metal different from the first metal layer 120, there is a possibility that the first metal layer 120 is not removed in the step of removing the stopper layer S.

[0101] The step of removing the temporary layer T can be performed by delamination, but is not limited thereto, and can also be performed by etching. Depending on the constituent material of the temporary layer T, it can be performed by different processes, and any process that can remove the constituent material of the temporary layer T can be used without restriction. That is, different conditions can be realized according to the material of the temporary layer T. Since a barrier layer 130 is formed between the temporary layer T and the first insulating layer 111, damage to the first insulating layer 111 can be prevented in the step of removing the temporary layer T. Also, since a part of the temporary layer T and a part of the barrier layer 130 are removed in the step of forming the groove g, the temporary layer T and the barrier layer 130 can be easily separated from each other.

[0102] Through the step of removing the temporary layer T, the protrusion 121 of the first metal layer 120 can protrude more than the first insulating layer 111. That is, the protrusion 121 of the first metal layer 120 can function as a metal post.

[0103] Referring to FIG. 15, the method for manufacturing a printed circuit board may further include a step of forming a surface treatment layer 140 on the first metal layer 120. The surface treatment layer 140 can be formed in a region of the first metal layer 120 that is exposed to the outside, and can be formed on the protrusion 121 of the first metal layer 120 and a part of the groove g. The surface treatment layer 140 can be formed by electroless plating and replacement plating, but is not necessarily limited thereto, and different manufacturing methods can be applied according to the structure of the surface treatment layer 140. Further, when the surface treatment layer is an organic film structure containing an organic substance, it can also be formed by organic film coating. The method of forming the surface treatment layer 140 in this way can be used without particular limitation as long as it is a method for forming the surface treatment layer 140 that can be used by those having ordinary knowledge in the technical field.

[0104] FIGS. 5 to 15 are shown assuming that the configuration is formed only on the lower side of the carrier substrate C based on each figure, but the same process can be performed on the upper surface of the carrier substrate C to manufacture a printed circuit board having a symmetric structure. In this case, two printed circuit boards having the same structure can be manufactured via one carrier substrate C. Further, it is not limited thereto, and after a plurality of substrates are realized in the form of a strip substrate on one carrier substrate C, each printed circuit board can be cut to manufacture a plurality of printed circuit boards.

[0105] In addition, it may further include a general configuration of a printed circuit board, as described above in the description of the printed circuit board, and can be freely added or omitted as long as the technical significance of the present invention is not changed.

[0106] In the present invention, the meaning in cross-section can mean the cross-sectional shape when the object is vertically cut, or the cross-sectional shape when the object is viewed in a side view. Further, the meaning on a plane can mean the shape when the object is horizontally cut, or the planar shape when the object is viewed in a top view or a bottom view.

[0107] In the present invention, terms such as "upper side, upper part, upper surface" are used, for the sake of convenience, to mean the direction toward the surface on which electronic components can be mounted based on the cross-section of the drawing, and terms such as "lower side, lower part, lower surface" are used to mean the opposite direction. However, this is only for the convenience of explanation and defines the direction, and it goes without saying that the scope of rights in the claims is not particularly limited by the description of such a direction.

[0108] In the present invention, "connected" includes not only being directly connected but also being indirectly connected via an adhesive layer or the like. Further, "electrically connected" is a concept that includes both the case of being physically connected and the case of not being connected. Furthermore, expressions such as "first, second" are used to distinguish one component from another component, and do not limit the order and / or importance of the said component. In some cases, within the scope not departing from the scope of rights, the first component may be named the second component, and similarly, the second component may be named the first component.

[0109] In the present invention, it can be judged including, for example, process errors, position deviations, errors during measurement, etc. that occur in the manufacturing process. For example, "substantially perpendicular" can include not only the case of being completely perpendicular but also the case of being approximately perpendicular. Further, "substantially coplanar" can include not only the case of existing on exactly the same plane but also the case of existing on approximately the same plane. Also, "substantially tapered" can include not only the case where the width changes with a completely constant inclination but also the case where the width generally changes such that the widths on one side and the opposite side are different.

[0110] In the present invention, the "same material" can mean not only completely identical materials, but also materials of the same type. Therefore, although the compositions of the materials are substantially the same, their specific composition ratios may vary slightly.

[0111] The expression "an example" used in the present invention does not mean the same embodiments as each other, but is provided to emphasize and explain their respective unique features. However, the above-provided examples do not exclude being combined with the features of other examples. For example, even if a matter described in a specific example is not described in other examples, in other examples, as long as there is no description contrary to or conflicting with that matter, it can be understood as an explanation related to other examples.

[0112] The terms used in the present invention are merely used to explain an example and are not intended to limit the present invention. At this time, the singular expression includes plural expressions unless the context clearly indicates a different meaning.

Explanation of Reference Numerals

[0113] 111: First insulating layer 112: Second insulating layer 120: First metal layer 121: Protrusion 122: Embedded portion 123: Protruding portion 125: Seed layer 126: Plated layer 130: Barrier layer 140: Surface treatment layer 151: First wiring layer 155: First via layer 152: First pad 153: First pattern 160: Solder resist layer C: Carrier substrate C1: Core C2: Seed S: Stopper layer T: Temporary layer h: Through hole g: groove 1000: electronic device 1010: main board 1020: chip-related components 1030: network-related components 1040: other components 1050: camera module 1060: antenna module 1070: display 1080: battery 1090: signal line 1100: smartphone 1110: main board inside the smartphone 1120: electronic components inside the smartphone 1121: antenna module inside the smartphone 1130: camera module inside the smartphone 1140: speaker inside the smartphone

Claims

1. A first insulating layer; a first metal layer, a portion of which protrudes above the first insulating layer and another portion of which is embedded within the first insulating layer; a barrier layer disposed on the first insulating layer; The barrier layer comprises an inorganic oxide film.

2. The printed circuit board of claim 1 , wherein the embedded portion of the first metal layer penetrates the upper and lower surfaces of the first insulating layer.

3. A second insulating layer disposed below the first insulating layer; a first wiring layer disposed on the second insulating layer; The printed circuit board according to claim 1 , further comprising: a first via layer penetrating at least a portion of the second insulating layer to connect the first wiring layer and the first metal layer to each other.

4. The printed circuit board of claim 3 , wherein the first and second insulating layers comprise substantially the same insulating material as each other.

5. The printed circuit board of claim 1 , wherein the barrier layer is disposed over at least a portion of the first insulating layer and contacts a side of the first metal layer.

6. The printed circuit board of claim 1 , wherein the barrier layer has a thickness less than a thickness of the first insulating layer.

7. the first metal layer includes a seed layer disposed on an outer side and a plating layer disposed on the seed layer; The printed circuit board of claim 1 , wherein the barrier layer has a thickness less than a thickness of the seed layer.

8. A first insulating layer; a first metal layer having a protruding portion protruding above the first insulating layer, a buried portion buried in the first insulating layer, and a protruding portion protruding toward an outer circumferential surface of the first metal layer; a barrier layer disposed on the first insulating layer; The protruding portion, the recessed portion and the protruding portion are integrally formed on the printed circuit board.

9. The printed circuit board according to claim 8 , wherein a portion of the protrusion is disposed inside the first insulating layer and another portion is disposed outside the first insulating layer.

10. A second insulating layer disposed below the first insulating layer; The printed circuit board of claim 8 , further comprising: a first wiring layer disposed on the second insulating layer, the first wiring layer including a first pad and a first pattern.

11. The printed circuit board of claim 10 , wherein a width between both ends of the protrusion is narrower than a width of the first pad.

12. The printed circuit board according to claim 8 , wherein the first metal layer includes a seed layer extending along the outside of the protruding portion, the protruding portion and the buried portion, and a plating layer disposed on the seed layer.

13. The printed circuit board of claim 8 , further comprising a surface treatment layer disposed on the first metal layer.

14. The printed circuit board according to claim 13 , wherein the surface treatment layer covers at least a portion of the protrusion and the projection.

15. The printed circuit board of claim 8 , wherein the recessed portion has an upwardly tapered shape.

16. The printed circuit board of claim 8 , wherein the barrier layer contacts the protrusion.

Images