TWI793139B - Printed circuit board - Google Patents

Abstract

A printed circuit board according to an aspect of the present invention comprises, an insulating layer of which a metal pad is formed on one surface; an opening part located on one surface of the metal pad and penetrating the insulating layer; a first protruding part located in the opening part and formed on one surface of the metal pad; a second protruding part formed on the other surface of the metal pad; and a filling member filling inside the opening part to be in contact with the first protruding part, wherein a melting point of the filling member is lower than that of the metal pad, and wherein the second protruding part projected on the other surface of the insulating layer is located in the opening part on the other surface of the insulating layer.

Description

A printed circuit board

The following description is for a printed circuit board.

There are parallel build up lamination and sequential lamination in the manufacture of printed circuit boards. Parallel build-up lamination involves high temperature pressing, while sequential lamination involves low temperature pressing. When using the parallel build-up lamination method, paste can be used as the connection structure between the unit layers. In such a case, the adhesion and connectivity between the internal wiring and the paste may deteriorate.

Japanese Laid-Open Patent No. 2003-179356 describes an example of a printed circuit board.

The object of the present invention is to provide a printed circuit board with excellent interlayer adhesion and connectivity.

According to an aspect of the present invention, a printed circuit board is provided, and the printed circuit board includes: an insulating layer, a metal pad is formed on one surface of the insulating layer; an opening part is located on a surface of the metal pad and penetrate the insulating layer; the first protruding part is located in the opening part and formed on the one of the metal pads a second protruding part formed on the other surface of the metal pad; and a filling member filled in the opening part to contact the first protruding part, wherein the filling member has a melting point lower than The melting point of the metal pad, and wherein the second protruding part projected on the other surface of the insulating layer is located in the opening part region on the other surface of the insulating layer.

According to another aspect of the present invention, a printed circuit board is provided. The printed circuit board includes: an insulating layer, a first metal pad is formed on one surface of the insulating layer and a second metal pad is embedded in the other surface. a metal pad; an opening part, located between the first metal pad and the second metal pad and penetrating through the insulating layer; a first protruding part, located in the opening part and facing from the first metal pad A surface of the first metal pad of the two metal pads protrudes; a second protruding part is located in the opening part and protrudes from a surface of the second metal pad facing the first metal pad. and a filling member filled in the opening part so that the first protruding part contacts the second protruding part, wherein a melting point of the filling member is lower than a melting point of the first metal pad.

1, 2, 3: Unit substrate

10: Opening parts

20, 30: through holes

100: insulating layer

110: metal pad/first metal pad

110a: a surface of the metal pad/a surface of the first metal pad

110b: the other surface of the metal pad/the other surface of the first metal pad

110c: side surface of the metal pad/side surface of the first metal pad

111: circuit/first circuit

120: first protruding part

120': third protruding part

130: electroless plating layer

140: Plating layer

150: seed layer

200: insulating layer/upper insulating layer

210: Second metal pad

210a: a surface of the second metal pad

211: second circuit

220: second protruding part

220': Fourth protruding part

230: electroless plating layer

300: insulating layer/lower insulating layer/third insulating layer

B: Back mask

C: Outermost circuit layer

F1, F2: protective film

M: metal foil

P1: filling member

P2, P3: through hole

R1, R2, R3: resist film

FIG. 1 shows a printed circuit board according to a first embodiment of the present invention.

Fig. 2 shows a printed circuit board according to a second embodiment of the invention.

Fig. 3 shows a printed circuit board according to a third embodiment of the present invention.

Fig. 4 shows a printed circuit board according to a fourth embodiment of the present invention.

Fig. 5 shows a printed circuit board according to a fifth embodiment of the present invention.

6(a) and 6(b) show a printed circuit board according to a sixth embodiment of the present invention.

7 to 19 are cross-sectional views illustrating processes used in a method of manufacturing a printed circuit board according to an embodiment of the present invention.

20 to 29(b) are cross-sectional views illustrating processes used in a method of manufacturing a printed circuit board according to another embodiment of the present invention.

Like reference numbers refer to like elements throughout the drawings and detailed description. The drawings may not be drawn to scale, and the relative size, proportion, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience.

The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, devices, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatus, and/or systems described herein will be apparent to those having ordinary skill in the art. The order of operations described herein are examples only and are not limited to those mentioned herein, but as would be apparent to one of ordinary skill in the art, unless operations must occur in a particular order Otherwise, changes may be made. Also, descriptions of functions and constructions that are well known to one having ordinary skill in the art may be omitted for increased clarity and certainty.

The features described herein may be implemented in different forms and should not be construed as limited to only the examples described herein. Rather, the examples described herein are provided so that this disclosure will be thorough and complete, and will convey to those of ordinary skill in the art. up to the full scope of the invention.

Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. Any terms defined in commonly used dictionaries should be construed as having the same meaning as in the context of the relevant technology, and unless otherwise clearly defined, should not be construed as having an idealized or overly formal meaning.

Regardless of the figure number, the same or corresponding components will be given the same reference numerals and will not be described repeatedly. Throughout the description of the present invention, when explaining a certain related conventional art is determined to be irrelevant to the gist of the present invention, the relevant detailed description will be omitted. Terms such as "first" and "second" may be used in describing various components, but the above components should not be limited to the above terms. The above terms are only used to distinguish individual components. In the drawings, some components may be exaggerated, omitted, or briefly shown, and the size of the components does not necessarily reflect the actual size of the components.

Hereinafter, specific embodiments of the present invention will be explained in detail with reference to the accompanying drawings.

FIG. 1 shows a printed circuit board according to a first embodiment of the present invention.

Referring to FIG. 1, a printed circuit board according to a first embodiment of the present invention includes an insulating layer 100 formed with a metal pad 110, an opening part 10 formed in the insulating layer 100, a first protruding part 120, a second protruding part 220, And the filling member P1 filled in the opening part 10 . Here, the filling member P1 may be a paste containing metal powder.

The insulating layer 100 is made of insulating material such as resin. The resin of the insulating layer 100 may be made of various materials such as thermosetting resin and thermoplastic resin.

The insulating layer 100 may be made of a material having a low dielectric constant (Dk) and a low dielectric loss (Df). Specifically, the insulating layer 100 can be made of liquid crystal polymer (liquid crystal polymer, LCP), polytetrafluoroethylene (polytetrafluoroethylene, PTFE), polyphenylene ether (polyphenylene ether, PPE), cyclo olefin polymer (cyclo olefin polymer, COP) , and at least one of polyperfluoroalkoxy (perfluoroalkoxy, PFA). However, it is not limited to this. All materials with low dielectric constant and low dielectric loss can be used. This material is suitable for reducing signal loss in substrates used to transmit high-frequency signals.

However, the insulating layer 100 is not limited to the above materials, and may be formed of epoxy resin, polyimide, or the like. Examples of the epoxy resin include naphthalene epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolak epoxy resin Resin (novolak epoxy resin), cresol novolak epoxy resin (cresol novolak epoxy resin), rubber modified epoxy resin (rubber modified epoxy resin), cycloaliphatic epoxy resin (cycloaliphatic epoxy resin), silicon epoxy Resin (silicon-based epoxy resin), nitrogen-based epoxy resin (nitrogen-based epoxy resin), phosphorus-based epoxy resin (phosphorus-based epoxy resin), etc. However, it is not limited to this.

The insulating layer 100 may be a prepreg including a fiber reinforcement material such as glass cloth in a resin. (prepreg, PPG). The insulating layer 100 may be a build-up film in which inorganic fillers such as silicon oxide (silica) are filled in a resin. As such a build-up film, an ajinomoto build-up film (ABF) or the like can be used.

Circuits 111 and metal pads 110 are formed on a surface of the insulating layer 100 . The circuit 111 is a conductor patterned to transmit electrical signals. The metal pad 110 is a conductor connected to the end of the circuit 111 . The circuit 111 and the metal pad 110 are made of metals such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof. form.

The opening part 10 is formed in the insulating layer 100 . The opening part 10 penetrates the insulating layer 100 to be positioned on a surface 110 a of the metal pad 110 . That is, at least a portion of a surface 110 a of the metal pad 110 is exposed through the opening part 10 . The opening part 10 may be formed in a cylindrical shape, but the area of one surface facing each other may be different from the area of the other surface. That is, the cross-sectional area of the opening member 10 can become larger toward the surface to be processed.

The first protruding part 120 is formed on a surface 110 a of the metal pad 110 and located in the opening part 10 . The first protruding part 120 protrudes upward from a surface 110 a of the metal pad 110 . The first protrusion member 120 may be formed of metal such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof. The first protruding part 120 can also be made of the same metal as the circuit 111 and the metal pad 110 .

The height (protrusion length) of the first protrusion part 120 is smaller than the height (thickness) of the opening part 10 . The area where the first protruding part 120 is in contact with the metal pad 110 is It is formed to be equal to or smaller than the area where the opening part 10 and the metal pad 110 contact each other (the area where the metal pad 110 is exposed through the opening part 10 ).

A space may be provided between a side surface of the first protrusion part 120 and the insulating layer 100 . The space may exist even if the area where the first protruding part 120 and the metal pad 110 contact each other is equal to the area where the opening part 10 and the metal pad 110 contact each other (the area where the metal pad 110 is exposed through the opening part 10 ).

The second protruding part 220 is formed on the other surface 110 b (the surface opposite to the one surface) of the metal pad 110 . The second protrusion part 220 protrudes in a direction opposite to the first protrusion part 120 . The second protruding member 220 may be formed of a metal such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or an alloy thereof, and It can also be made of the same metal as the circuit 111 and the metal pad 110 .

When the second protruding part 220 is projected on the other surface of the insulating layer 100 , the second protruding part 220 projected on the other surface of the insulating layer 100 may be formed in the opening part in the other surface of the insulating layer 100 10 in the area. That is, when the upper surface of the second protrusion part 220 is moved parallel to the other surface of the insulating layer 100 , the second protrusion part 220 is positioned in the opening part 10 . In addition, when the second protruding part 220 is symmetrical to the plane of the metal pad 110 , the second protruding part 220 can be positioned in the opening part 10 .

The height (protrusion length) of the second protrusion part 220 is smaller than the height (thickness) of the opening part 10 .

An electroless plating layer can be formed on the surface of the circuit 111 and the surface of the metal pad 130. The electroless plating layer 130 may be formed on the surface of the circuit 111 not in contact with the insulating layer 100 and the surface of the metal pad. Specifically, the electroless plating layer 130 may be formed on the other surface 110 b and the side surface 110 c of the metal pad 110 . The electroless plating layer 130 may not be formed on a surface 110 a of the metal pad 110 .

The second protruding part 220 may be formed on the electroless plating layer 130 formed on the other surface 110 b of the metal pad 110 . When the first protruding part 120 and the second protruding part 220 are formed by electroplating, the electroless plating layer 130 becomes a lead-in wire.

The filling member P1 is filled in the opening part 10 and contacts the first protruding part 120 . The filling height of the filling member P1 may be equal to or greater than the height of the opening part 10 . The filling member P1 has conductivity and may be a paste containing metal such as copper (Cu), tin (Sn), silver (Ag), and the like. However, the filling member P1 is not limited to this material. All conductive materials can be used. The filling member P1 may have a lower melting point than other conductors in the printed circuit board. Specifically, the melting point of the filling member P1 may be lower than the melting point of at least one of the circuit 111 , the metal pad 110 , the first protruding part 120 , and the second protruding part 220 . Preferably, the filling member P1 may have the lowest melting point among the printed circuit boards.

When a space is provided between the side surface of the first protrusion part 120 and the insulating layer 100 , the filling member P1 may be filled in the space.

Fig. 2 shows a printed circuit board according to a second embodiment of the invention.

Referring to FIG. 2, a printed circuit board according to a second embodiment of the present invention includes an insulating layer 100 formed with a first metal pad 110 and a second metal pad 210, formed on The opening part 10 on the insulating layer 100 , the first protruding part 120 , the second protruding part 220 , and the filling member P1 filled in the opening part 10 . Here, the filling member P1 may be a paste containing metal powder.

The insulating layer 100 is made of insulating material such as resin. The resin of the insulating layer 100 may be made of various materials such as thermosetting resin and thermoplastic resin.

The insulating layer 100 may be made of a material having a low dielectric constant (Dk) and a low dielectric loss (Df). Specifically, the insulating layer 100 can be made of liquid crystal polymer (LCP), polytetrafluoroethylene (PTFE), polyphenylene ether (PPE), cycloolefin polymer (COP), and polyperfluoroalkoxy (PFA). At least one is made. However, it is not limited to this. All materials with low dielectric constant and low dielectric loss can be used. This material is suitable for reducing signal loss in substrates used to transmit high-frequency signals.

However, the insulating layer 100 is not limited to the above materials, and may be epoxy resin, polyimide, or the like. Its description is the same as the above description.

A first circuit 111 and a first metal pad 110 are formed on a surface of the insulating layer 100 . A second circuit 211 and a second metal pad 210 are formed on the other surface of the insulating layer 100 . The first circuit 111 and the second circuit 211 are conductors that are patterned to transmit electrical signals. The first metal pad 110 is a conductor connected to the end of the first circuit 111 , and the second metal pad 210 is a conductor connected to the end of the second circuit 211 .

The first circuit 111 and the first metal pad 110 are formed on one surface of the insulating layer 100 , and the second circuit 211 and the second metal pad 210 are embedded in the other surface of the insulating layer 100 .

The first circuit 111, the second circuit 211, the first metal pad 110, and the second The two metal pads 210 may be formed of metals such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof.

The opening part 10 is formed in the insulating layer 100 . The opening part 10 penetrates the insulating layer 100 to be positioned between the first metal pad 110 and the second metal pad 210 . The opening part 10 contacts a surface 110 a of the first metal pad 110 and a surface 210 a of the second metal pad 210 . The opening part 10 may be formed in a cylindrical shape, but the cross-sectional area of the opening part 10 may increase from the first metal pad 110 toward the second metal pad 210 .

The first protruding part 120 is formed on a surface 110 a of the first metal pad 110 and located in the opening part 10 . The first protruding part 120 protrudes from a surface 110 a of the first metal pad 110 facing the second metal pad 210 . The first protrusion member 120 may be formed of metal such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof.

The height (protrusion length) of the first protrusion part 120 is smaller than the height (thickness) of the opening part 10 . The area where the first protruding part 120 and the first metal pad 110 contact each other may be equal to or smaller than the area where the opening part 10 and the first metal pad 110 contact each other (the area where the first metal pad 110 is exposed through the opening part 10 ). .

A space may be provided between a side surface of the first protrusion part 120 and the insulating layer 100 . Even if the area where the first protruding part 120 and the first metal pad 110 contact each other is equal to the area where the opening part 10 and the first metal pad 110 contact each other (the area where the metal pad 110 is exposed through the opening part 10), there may still be the space.

The second protruding part 220 is formed on a surface 210 a of the second metal pad 210 and located in the opening part 10 . The second protruding part 220 faces the first metal A surface 210 a of the second metal pad 210 of the pad 110 protrudes. The second protrusion part 220 may be formed of metal such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof.

A third protruding part 120' having the same structure as the first protruding part 120 may be formed on the other surface of the second metal pad 210. Referring to FIG. A fourth protruding part 220' having the same structure as the second protruding part 220 may be formed on the other surface 110b of the first metal pad 110. Referring to FIG. That is, the structure of the metal pad 110 and the protruding part can be repeatedly formed on one surface and the other surface of the insulating layer 100 . However, all of the first to fourth protruding parts may not be formed together, and the third protruding part 120' and the fourth protruding part 220' may be formed as required. For example, as will be described later, when an additional insulating layer 100 is laminated on the upper and lower portions of the insulating layer 100 and interlayer connections are made through via holes, the third protruding part 120' or the fourth protruding part 220' may contacts the vias.

The electroless plating layer 130 can be formed on the surface of the first circuit 111 and the first metal pad 110 and on the surface of the second circuit 211 and the second metal pad 210 . The electroless plating layer 130 is formed on the surface of the first circuit 111 and the surface of the first metal pad 110 that are not in contact with the insulating layer 100 . The electroless plating layer 130 is formed on the surface of the second circuit 211 in contact with the insulating layer 100 and the surface of the second metal pad 210 . Specifically, the electroless plating layer 130 can be formed on the other surface 110 b and the side surface 110 c of the first metal pad 110 , and on the one surface 210 a and the side surface of the second metal pad 210 .

The second protruding part 220 may be formed on a surface of the second metal pad 210 On the electroless plating layer 130 formed on the surface 210a. The fourth protruding part 220' may be formed on the electroless plating layer 130 formed on the other surface 110b of the first metal pad 110. Referring to FIG. When the first to fourth protrusion parts are formed by electroplating, the electroless plating layer 130 becomes the lead-in.

The filling member P1 is filled in the opening part 10 and contacts the first protruding part 120 and the second protruding part 220 . The filling member P1 is conductive and may be a paste containing metal such as copper (Cu), tin (Sn), silver (Ag), and the like. However, the filling member P1 is not limited to this material. All conductive materials can be used. The filling member P1 may have a lower melting point than other conductors in the printed circuit board. Specifically, the melting point of the filling member P1 may be lower than the melting point of at least one of the circuit 111 , the metal pad 110 , the first protruding part 120 , and the second protruding part 220 . Preferably, the filling member P1 may have the lowest melting point among the printed circuit boards.

When a space is provided between the side surface of the first protrusion part 120 and the insulating layer 100 , the filling member P1 may be filled in the space.

Fig. 3 shows a printed circuit board according to a third embodiment of the present invention.

Referring to FIG. 3 , a printed circuit board according to a third embodiment of the present invention includes an insulating layer 200 and an insulating layer 300 formed on an upper portion and/or a bottom portion of an insulating layer 100 as shown in FIG. 1 or 2 .

In detail, in addition to the insulating layer 100, the protruding part, and the filling member P1, the printed circuit board according to the third embodiment of the present invention further includes an upper insulating layer 200, a lower insulating layer 300, and through holes P2 and P3.

The upper insulating layer 200 is laminated on the upper portion of the insulating layer 100 and the lower portion The insulating layer 300 is laminated on the lower portion of the insulating layer 100 . The detailed description thereof is the same as that explained above for the insulating layer 100 . The upper insulating layer 200 and the lower insulating layer 300 are not necessarily laminated on the upper portion and the lower portion of the insulating layer 100 together, but may be selectively laminated. That is, if the insulating layer 100 described above is located at the uppermost or lowermost portion of the multilayer printed circuit board, the upper insulating layer 200 or the lower insulating layer 300 may be laminated on the insulating layer 100 .

The upper insulating layer 200 may include a via hole P2. The through hole P2 of the upper insulating layer 200 is located on the other surface of the second metal pad 210 and penetrates the upper insulating layer 200 . Here, the third protruding part 120' formed on the other surface of the second metal pad 210 may be recessed into the through hole P2. Specifically, when the via hole P2 is formed by filling the metal paste in the via hole 20, the third protruding part 120' may be recessed into the via hole P2 by parallel build-up lamination. The through hole P2 may be the same material as the filling member P1 filled in the opening part 10 described above.

The lower insulating layer 300 also includes a via hole P3. The through hole P3 of the lower insulating layer 300 is located under the other surface 110 b of the first metal pad 110 and penetrates through the lower insulating layer 300 . Here, the fourth protruding part 220' formed on the other surface 110b of the first metal pad 110 may be recessed into the through hole P3. Specifically, when the via hole P3 is filled in the via hole 30 with metal paste, the fourth protruding part 220' can be recessed into the via hole P3 by parallel build-up lamination. The through hole P3 may be the same material as the filling member P1 filled in the opening part 10 described above.

The structure of such protruding parts can be repeatedly formed in the plurality of insulating layers 100 , 200 , and 300 . However, not necessarily all of the plurality of insulating layers 100, 200, and 300 have protruding features, and the protruding features can be selectively formed in one or more desired insulating layers.

The via holes P2 and P3 and the opening part 10 of the insulating layer 100 may be arranged to overlap each other in a vertical direction. Preferably, the opening part 10 and the through holes P2 and P3 can be arranged in a line in the vertical direction.

Fig. 4 shows a printed circuit board according to a fourth embodiment of the present invention.

Referring to FIG. 4 , in the printed circuit board according to the fourth embodiment of the present invention, no space may be provided between the side surface of the first protruding part 120 and the insulating layer 100 as compared with the first to third embodiments. That is, the side surface of the first protrusion part 120 and the insulating layer 100 may contact each other. In this case, the first protruding part 120 is formed on the entire surface of the opening part 10 (the area where the metal pad 110 is exposed through the opening part 10 in contact with the metal pad 110).

Since other detailed descriptions are the same as those of the first embodiment to the third embodiment, they will not be repeated here.

Fig. 5 shows a printed circuit board according to a fifth embodiment of the present invention.

Referring to FIG. 5 , in the printed circuit board according to the fifth embodiment of the present invention, compared with the second and third embodiments, the first protruding part 120 and the second protruding part 220 are in contact with each other. In this case, the sum of the height of the first protruding part 120 and the height of the second protruding part 220 may be equal to or greater than the thickness of the opening part 10 . Inter-layer transmission of signals is performed through the first protruding part 120 and the second protruding part 220, so that the signal transmission speed can be fast.

Fig. 6 (a) and Fig. 6 (b) show the print according to the sixth embodiment of the present invention Brush the circuit board.

Referring to FIG. 6, the printed circuit board according to the sixth embodiment of the present invention includes an insulating layer 100 on which a first metal pad 110 and a second metal pad 210 are formed, an opening part 10 located in the insulating layer 100, a first The protruding part 120 , the second protruding part 220 , and the filling member P1 filled in the opening part 10 . The filling member P1 may be a metal paste containing metal powder.

The insulating layer 100 is made of insulating material such as resin. The resin of the insulating layer 100 may be made of various materials such as thermosetting resin and thermoplastic resin.

The insulating layer 100 may be made of a material having a low dielectric constant (Dk) and a low dielectric loss (Df). Specifically, the insulating layer 100 can be made of liquid crystal polymer (LCP), polytetrafluoroethylene (PTFE), polyphenylene ether (PPE), cycloolefin polymer (COP), and polyperfluoroalkoxy (PFA). At least one is made. However, it is not limited to this. All materials with low dielectric constant and low dielectric loss can be used. This material is suitable for reducing signal loss in substrates used to transmit high-frequency signals.

However, the insulating layer 100 is not limited to the above materials, and may be formed of epoxy resin, polyimide, or the like. Its description is the same as the above description.

A first circuit 111 and a first metal pad 110 are formed on a surface of the insulating layer 100 . A second circuit 211 and a second metal pad 210 are formed on the other surface of the insulating layer 100 . The first circuit 111 and the first metal pad 110 are formed on one surface of the insulating layer 100 , and the second circuit 211 and the second metal pad 210 are embedded in the other surface of the insulating layer 100 .

The first circuit 111, the second circuit 211, the first metal pad 110, and the second The two metal pads 210 may be formed of metals such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof.

The opening part 10 is formed in the insulating layer 100 . The opening part 10 penetrates the insulating layer 100 to be positioned between the first metal pad 110 and the second metal pad 210 . The opening part 10 contacts a surface 110 a of the first metal pad 110 and a surface 210 a of the second metal pad 210 . The opening part 10 may be formed in a cylindrical shape, but the cross-sectional area of the opening part 10 may increase from the first metal pad 110 toward the second metal pad 210 .

The first protruding part 120 is formed on a surface 110 a of the first metal pad 110 and located in the opening part 10 . The first protruding part 120 protrudes from a surface 110 a of the first metal pad 110 facing the second metal pad 210 . The first protrusion member 120 may be formed of metal such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof.

A side surface of the first protrusion part 120 and the insulating layer 100 may contact each other. In this case, the first protruding part 120 is formed on the entire surface of the opening part 10 contacting the metal pad 110 (the area where the metal pad 110 is exposed through the opening part 10 ).

The printed circuit board according to the sixth embodiment of the present invention further includes a plating layer 140 extending from the first protruding part 120 along the inner sidewall of the opening part 10 . In this case, since the first protruding part 120 and the electroplating layer 140 are formed simultaneously by electroplating, no interface may be formed between the first protruding part 120 and the electroplating layer 140 .

As shown in FIG. 6( a ), the first protruding part 120 and the plating layer 140 may be formed to have the same thickness. However, as shown in Fig. 6(b), the first protrusion The thickness of the member 120 may be greater than the thickness of the plating layer 140 . In the latter case, since the first protruding part 120 and the plating layer 140 are formed by isotropic electroplating, the thickness of the first protruding part 120 may be relatively large.

The printed circuit board according to the sixth embodiment of the present invention may further include a seed layer 150 located on the bottom portion of the first protruding member 120 and the bottom portion of the plating layer 140 . That is, the seed layer 150 may be formed along the inner sidewall of the opening part 10 and a surface 110 a of the first metal pad 110 exposed through the opening part 10 . The seed layer 150 may be formed by electroless plating and becomes the lead-in for electrolytic plating. The seed layer 150 may be formed to a thickness of 2 micrometers (μm) or less.

The second protruding part 220 is formed on a surface 210 a of the second metal pad 210 and located in the opening part 10 . The second protruding part 220 protrudes from a surface 210 a of the second metal pad 210 facing the first metal pad 110 . The second protrusion part 220 may be formed of metal such as copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), or alloys thereof.

As shown in FIGS. 6( a ) and 6 ( b ), the second protruding part 220 may be formed not to contact the plating layer 140 , but the second protruding part 220 may be formed to contact the plating layer 140 .

A third protruding part 120' having the same structure as the first protruding part 120 may be formed on the other surface of the second metal pad 210. Referring to FIG. Here, the plating layer 140 may also be formed to extend from the third protruding part 120'. A fourth protruding part 220' having the same structure as the second protruding part 220 may be formed on the other surface 110b of the first metal pad 110. Referring to FIG. That is, the structure of the metal pad 110 and the protruding part can be repeated formed on one surface and the other surface of the insulating layer 100 . However, all of the first to fourth protruding parts may not be formed together, and the third protruding part 120' and the fourth protruding part 220' may be formed as required.

The filling member P1 is filled in the opening part 10 and contacts the first protruding part 120 and the second protruding part 220 . The filling member P1 is conductive and may be a paste containing metal such as copper (Cu), tin (Sn), silver (Ag), and the like. However, the filling member P1 is not limited to this material. All conductive materials can be used. The filling member P1 may have a lower melting point than other conductors in the printed circuit board. Specifically, the melting point of the filling member P1 may be lower than the melting point of at least one of the circuit 111 , the metal pad 110 , the first protruding part 120 , and the second protruding part 220 . Preferably, the filling member P1 may have the lowest melting point among the printed circuit boards.

Hereinafter, a method of manufacturing a printed circuit board will be explained.

7 to 19 are cross-sectional views illustrating processes used in a method of manufacturing a printed circuit board according to an embodiment of the present invention.

Referring to FIG. 7 , a board in which a metal foil M is laminated on one surface and the other surface of an insulating layer 100 is prepared. The metal foil M corresponds to the circuit 111 and the metal pad 110 , and can be a metal such as copper. Metal foil M may have a thickness of 18 micrometers. As an insulating material such as liquid crystal polymer (LCP), the insulating layer 100 may have a thickness of 50 micrometers.

Referring to FIG. 8 , the metal foil M laminated on the other surface of the insulating layer 100 is removed. The removal of the metal foil M may be performed by half etching. When half-etching is performed, on the unetched metal foil M, for example, foam tape (foam tape) is laminated. tape) or the like (not shown) and the film is used as an etch mask. However, in preparing the board, a board in which the metal foil M is laminated on only one surface of the insulating layer 100 is provided so that the processes shown in FIGS. 7 and 8 can be reduced.

Referring to FIGS. 9 and 10 , a resist film R1 is applied on the metal foil M. As shown in FIG. The resist film R1 may be a dry film. A film (not shown) such as foam tape is laminated on the surface of the insulating layer 100 on which the metal foil M is not formed so that the surface can be protected. The resist film R1 is photosensitive and selectively exposed using a mask. When the resist film R1 is a negative type, the regions other than the regions where the circuits 111 and the metal pads 110 are formed in the resist film R1 are exposed and photo-cured. Thereafter, the resist film R1 in the area where the circuit 111 and the metal pad 110 are formed is removed by a developing process, and a conductor is formed in the corresponding area by a plating process or the like.

Referring to FIG. 11 , an electroless plating layer 130 is continuously formed on the surfaces of the circuit 111 and the metal pad 110 and on one surface of the insulating layer 100 . The electroless plating layer 130 may be formed by electroless plating a metal such as copper.

Referring to FIG. 12 , a resist film R2 is coated on the electroless plating layer 130 again. The resist film R2 in the region where the second protruding part 220 will be formed is selectively removed. In this case, the resist film R2 may be selectively removed by a photolithography method.

13 and 14, the protective film F1 may be formed on the other surface of the insulating layer 100, and the opening part 10 may be formed in the other surface of the insulating layer 100 as the processed surface. The opening part 10 can be formed by laser processing such as CO ₂ laser. The protective film F1 can be polyethylene terephthalate (PET) and prevents burrs that may occur during laser processing.

The opening part 10 is formed on the first metal pad 110 to expose a surface 110 a of the first metal pad 110 . The bottom diameter of the opening part 10 is smaller than the diameter of the first metal pad 110 .

Referring to FIG. 15, the first protruding part 120 and the second protruding part 220 are formed by plating. The first protruding part 120 and the second protruding part 220 may be formed by electroplating, using the electroless plating layer 130 as the lead-in wire. When the formation of the second protruding part 220 is completed, the resist film R2 is removed.

Plating conditions may be adjusted such that the side surface of the first protrusion part 120 may be separated from or contact the insulating layer 100 .

Referring to FIG. 16 , unnecessary electroless plating layer 130 is removed by etching, and a back mask B is attached on one surface of insulating layer 100 . The back mask B minimizes any effects on the substrate as it is subjected to handling during processing.

Referring to FIG. 17 , the filling member P1 is filled in the opening part 10 . The filling member P1 may be a metal-containing paste. The filling member P1 may be printed in the opening part 10 under vacuum or atmospheric pressure conditions, and the filling member P1 may be printed, for example, by screen printing or the like.

Referring to FIG. 18, the protection film F1 and the back mask B are removed to provide a unit substrate. A plurality of unit substrates are formed.

19, the plurality of unit substrates 1, 2, and 3 are vertically Aligned upward and then the plurality of unit substrates 1, 2, and 3 are pressed together at a temperature of 300°C or higher. By such lamination, the second protruding part 220 and the fourth protruding part 220' are recessed into the relatively soft filling member P1. The filling member P1 filled in the opening part 10 can perform interlayer signal transmission.

The second protruding part 220 is recessed into the filling member P1 and the first protruding part 120 is located inside the filling member P1. The first protrusion part 120 and the second protrusion part 220 may contact each other in the filling member P1.

20 to 29(b) are cross-sectional views illustrating processes used in a method of manufacturing a printed circuit board according to another embodiment of the present invention.

Referring to FIG. 20 , there is provided a board in which a metal foil is laminated on only one surface of the insulating layer 100 . The circuit 111 and the metal pad 110 are formed by patterning the metal foil M. Such a board can be prepared by preparing a board in which a metal foil M is laminated on one surface and the other surface of the insulating layer 100 and then removing the metal foil M laminated on the other surface of the insulating layer 100 . In addition, the circuit 111 and the metal pad 110 can be formed by a photolithography process using a resist film.

Referring to FIG. 21, a resist film R3 covering the circuit 111 and the metal pad 110 is laminated on one surface of the insulating layer 100, and the resist film R3 on a region where the second protruding part 220 will be formed is removed. Removal of the resist film R3 may be performed through exposure and development processes.

Referring to FIG. 22 and FIG. 23 , the protective film F1 is attached to the other surface of the insulating layer 100 , and the opening part 10 is processed by using the other surface of the insulating layer 100 as a processing surface. The opening part 10 can be formed by laser processing such as CO ₂ laser. The protective film F1 may be PET and prevents burrs that may occur during laser processing.

The opening part 10 is formed on the first metal pad 110 to expose a surface 110 a of the first metal pad 110 . The bottom diameter of the opening part 10 is smaller than the diameter of the first metal pad 110 .

Referring to FIG. 24 , a seed layer 150 is formed in the opening part 10 and on the other surface of the insulating layer 100 . The seed layer 150 may be formed by electroless plating. The seed layer 150 may be formed after the protective film F1 is removed.

25(a) and 25(b), the first protruding part 120 and the plating layer 140 are formed on the seed layer 150, and the resist film R3 is removed. The first protruding part 120 is formed on a surface of the metal pad 110 and the plating layer 140 is formed to extend from the first protruding part 120 along the inner sidewall of the opening part 10 . The first protruding part 120 and the electroplating layer 140 may be formed simultaneously by electrolytic plating.

As shown in FIG. 25( a ), the thickness of the first protruding part 120 and the thickness of the plating layer 140 may be equal to each other. In addition, compared to FIG. 25( a ), as shown in FIG. 25( b ), the plating time may be increased so that the thickness of the first protruding part 120 is greater than the thickness of the plating layer 140 .

Referring to FIGS. 26 and 27 , after the back mask B is attached to one surface of the insulating layer 100 and the protective film F2 is attached to the other surface of the insulating layer 100 , the filling member P1 is filled in the opening part 10 . The protective film F2 may be PET. The filling member P1 may be a metal-containing paste. The filling member P1 may be printed in the opening part 10 by a screen printing method.

Referring to FIG. 28, peel off both the back mask B and the protective film F2, and prepare Multiple unit substrates.

Referring to FIGS. 29( a ) and 29 ( b ), the plurality of unit substrates 1 , 2 , and 3 are laminated together after the plurality of unit substrates 1 , 2 , and 3 are bonded together. Finally, Fig. 29(a) corresponds to Fig. 6(a) and Fig. 29(b) corresponds to Fig. 6(b). In parallel build-up lamination, the outermost circuit layer C may also be laminated together.

Although this disclosure includes specific examples, it will be apparent to those skilled in the art that various forms may be made in these examples without departing from the spirit and scope of claims and equivalents thereof. and changes in details. The examples set forth herein should be considered in an illustrative sense only and not in a limiting sense. Descriptions of features or aspects within each example should be considered as available for similar features or aspects in the other examples. If the described techniques are performed in a different order and/or if components in the described system, architecture, device, or circuit are combined in a different manner and/or are substituted or supplemented with other components or their equivalents, then achieve suitable results. Therefore, the scope of the present invention is not defined by the detailed description, but by the scope of the patent application and its equivalent scope, and all changes within the scope of the patent application and its equivalent scope should be deemed to be included in the present invention middle.

10‧‧‧opening parts

100‧‧‧Insulation layer

110‧‧‧Metal pad/first metal pad

110a‧‧‧a surface of the metal pad/a surface of the first metal pad

110b‧‧‧The other surface of the metal pad/the other surface of the first metal pad

110c‧‧‧The side surface of the metal pad/the side surface of the first metal pad

111‧‧‧circuit/first circuit

120‧‧‧The first protruding part

130‧‧‧Electroless coating

220‧‧‧The second protruding part

P1‧‧‧Filler

Claims (27)

A printed circuit board comprising: an insulating layer having a metal pad formed on one surface of the insulating layer; an opening part positioned on one surface of the metal pad and penetrating through the insulating layer; a first protruding part, located in the opening part and formed on the one surface of the metal pad; a second protruding part formed on the other surface of the metal pad; and a filling member filled in the opening part to contact the first protruding part, wherein the melting point of the filling member is lower than the melting point of the metal pad, and wherein the second protruding part projected on the other surface of the insulating layer is on the other side of the insulating layer The other surface of is located in the opening part, and wherein the first height of the first protruding part is smaller than the thickness of the opening part, and the second height of the second protruding part is smaller than the opening part of the thickness. The printed circuit board according to claim 1, wherein a space is provided between a side surface of the first protruding part and the insulating layer and the filling member is filled in the space. The printed circuit board according to claim 1, wherein the side surface of the first protruding member contacts the insulating layer. The printed circuit board according to claim 3 of the patent application further includes an electroplating layer extending from the first protruding part along the inner sidewall of the opening part. The printed circuit board as described in item 4 of the patent scope of the application, wherein said item A protruding part has a thickness greater than that of the plating layer. The printed circuit board according to claim 1 of the patent application, wherein the sum of the height of the first protruding part and the height of the second protruding part is equal to or greater than the thickness of the opening part. The printed circuit board according to claim 1, wherein an electroless plating layer is formed on the other surface and the side surface of the metal pad. The printed circuit board according to claim 7, wherein the electroless plating layer is not formed on the one surface of the metal pad. The printed circuit board as described in item 1 of the patent scope of the application, wherein the insulating layer is made of liquid crystal polymer (LCP), polytetrafluoroethylene (PTFE), polyphenylene ether (PPE), cycloolefin polymer ( COP), and at least one of polyperfluoroalkoxy (PFA). A printed circuit board, comprising: an insulating layer, a first metal pad is formed on one surface of the insulating layer and a second metal pad is embedded in the other surface; an opening part is located on the first metal pad Between the second metal pad and through the insulating layer; a first protruding part, located in the opening part and facing from a surface of the first metal pad facing the second metal pad protruding; a second protruding part located in the opening part and protruding from a surface of the second metal pad facing the first metal pad; and a filling member filled in the opening part so that the The first protruding part connects touches the second protruding part, wherein the melting point of the filling member is lower than the melting point of the first metal pad, and wherein the first height of the first protruding part is smaller than the thickness of the opening part, and the The second height of the second protruding part is smaller than the thickness of the opening part. The printed circuit board according to claim 10, wherein the insulating layer is provided between the side surface of the first protruding member and the insulating layer There is a space and the filling member is filled in the space. The printed circuit board according to claim 10, wherein the side surface of the first protruding member contacts the insulating layer. The printed circuit board according to claim 10, wherein the first protruding part contacts the second protruding part. The printed circuit board according to claim 10, wherein an electroless plating layer is formed on the other surface and the side surface of the first metal pad. The printed circuit board according to claim 14, wherein the electroless plating layer is not formed on the one surface of the first metal pad. The printed circuit board as described in item 10 of the patent scope of the application, wherein the insulating layer is made of liquid crystal polymer (LCP), polytetrafluoroethylene (PTFE), polyphenylene ether (PPE), cycloolefin polymer ( COP), and at least one of polyperfluoroalkoxy (PFA). The printed circuit board described in item 10 of the scope of the patent application further includes: An upper insulating layer is formed on an upper portion of the insulating layer; and a via hole is formed on the other surface of the second metal pad and penetrates the upper insulating layer. The printed circuit board as described in claim 10 of the patent application further includes a third protruding part formed on the other surface of the second metal pad. The printed circuit board as described in claim 18 of the scope of the patent application, further comprising: an upper insulating layer formed on the upper portion of the insulating layer; and a via hole formed on the other of the second metal pad. on the surface and through the upper insulating layer. The printed circuit board according to claim 19, wherein at least part of the opening member and at least part of the through hole are arranged to overlap in the vertical direction. The printed circuit board as claimed in claim 18 further includes a fourth protruding part formed on the other surface of the first metal pad. The printed circuit board according to claim 21, further comprising: a lower insulating layer formed on a bottom portion of the insulating layer; and a via hole located on the other surface of the first metal pad below and through the lower insulating layer, wherein the fourth protruding part is recessed in the through hole. The printed circuit board as described in claim 10, further comprising: a lower insulating layer formed on a bottom portion of the insulating layer; and a via hole located on the other surface of the first metal pad below and through the lower insulating layer. A printed circuit board comprising: an insulating layer having a metal pad formed on one surface of the insulating layer; an opening part positioned on one surface of the metal pad and penetrating through the insulating layer; a first protruding part, located in the opening part and formed on the one surface of the metal pad; a second protruding part formed on the other surface of the metal pad; a filling member filled in the opening part to contacting the first protruding part; and a plating layer extending from the first protruding part along an inner sidewall of the opening part, wherein the filling member has a melting point lower than that of the metal pad, wherein the projection on the The second protruding part on the other surface of the insulating layer is located in the opening part on the other surface of the insulating layer, wherein the seed layer is along the inner sidewall of the opening part and via A surface of the metal pad exposed by the opening part is formed under the first protruding part and the electroplating layer. A printed circuit board, comprising: an insulating layer, a first metal pad is formed on one surface of the insulating layer and a second metal pad is embedded in the other surface; an opening part is located on the first metal pad between the second metal pad and through the insulating layer; the first protruding part is located in the opening part and faces the second metal pad A surface of the first metal pad of the pad protrudes; a second protruding part is located in the opening part and protrudes from a surface of the second metal pad facing the first metal pad; filling a member filled in the opening part so that the first protruding part contacts the second protruding part; and a plating layer extending from the side surface of the first protruding part along an inner side wall of the opening part , wherein the filling member has a melting point lower than that of the first metal pad. The printed circuit board as described in item 25 of the scope of the patent application, wherein the seed layer is on the side of the first metal pad exposed along the inner sidewall of the opening part and the opening part. The first protruding part is formed under the electroplating layer. The printed circuit board according to claim 25, wherein the thickness of the first protruding part is greater than the thickness of the electroplating layer.

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