TWI832839B - Printed circuit board - Google Patents

Abstract

A printed circuit board in accordance with an aspect of the present disclosure includes: first insulating layer; second insulating layer made of a flexible material and laminated on the first insulating layer; first circuit formed on a lower surface of the first insulating layer and embedded in the first insulating layer; second circuit formed on a lower surface of the second insulating layer and laminated in the first insulating layer; and third circuit formed on an upper surface of the second insulating layer, wherein a pitch of the second circuit is smaller than a pitch of the first circuit.

Description

printed circuit board

The invention relates to a printed circuit board.

When printed circuit boards used for packaging are required to be thin and small, there is also a requirement to form fine-pitch wiring on these printed circuit boards. The thickness of the printed circuit board can be controlled to a minimum through a coreless method or by using thin materials. In addition, the width and space of the wiring can be controlled to have a precise pitch through a modified Semi-Additive Process (MSAP) or a Semi-Additive Process (SAP).

Related technology is described in Korean Patent No. 10-1593280 (February 11, 2016).

The present invention is directed to a printed circuit board including precision pitch circuits.

An aspect of the present invention provides a printed circuit board, which includes: a first insulating layer; a second insulating layer made of flexible material and laminated on the first insulating layer; and a first circuit forming on the lower surface of the first insulating layer and embedded in the first insulating layer; a second circuit formed on the lower surface of the second insulating layer and laminated in the first insulating layer; and The third circuit, formed in the On the upper surface of the second insulating layer, the pitch of the second circuit is smaller than the pitch of the first circuit.

100:Insulating materials

100a: Reinforcement material

100b: Through passage

110: First insulation layer

120: Second insulation layer

130:Third insulation layer

140:Fourth insulation layer

210:First circuit

220: Second circuit

230:Third circuit

240: Fourth circuit

250:Fifth circuit

260:Sixth Circuit

310:First Passage

320:Second channel

330:Third channel

340:Fourth channel

350, 360: Integrated channel

410:First pad

420:Second pad

430:Third pad

440:Fourth pad

450:Fifth pad

460:Sixth pad

500: Connecting parts

600: Solder mask

(a), (b), (c), (d), (e), (f), (g): steps

D: Remove the core

M1, M2, M3: metal layer

P, P’: conductive paste

S: seed metal layer

VH1, VH2, VH3, VH4, VH5, VH5’, VH6, VH7, VH7’: through hole

Figure 1 shows a printed circuit board according to an embodiment of the invention.

Figure 2 shows a printed circuit board according to an embodiment of the invention.

Figure 3 shows a printed circuit board according to an embodiment of the invention.

4 and 5 illustrate a method of manufacturing a printed circuit board according to an embodiment of the present invention.

Figure 6 illustrates a method of manufacturing a printed circuit board according to an embodiment of the invention.

7 and 8 illustrate a method of manufacturing a printed circuit board according to an embodiment of the present invention.

The following detailed description is provided to assist the reader in fully understanding the methods, apparatus, and/or systems described herein. However, various modifications, modifications, and equivalents to the methods, apparatus, and/or systems described herein will be apparent to those skilled in the art. The order of operations described herein is an example only, and is not limited to the examples described herein, but as one skilled in the art will understand, changes may be made, except for operations that must occur in a specific order. In addition, descriptions of functions and structures well known to those skilled in the art may be omitted for the sake of clarity and conciseness.

Features described herein may be embodied in different forms and should not be construed as limited to the examples described herein. Instead, the examples described in this article have been provided to This disclosure will be thorough and complete, and will fully convey the full scope of the invention to those skilled in the art.

Unless otherwise defined, all terms including technical terms and scientific terms used herein have the same meaning as commonly understood by those familiar with the invention. Any term defined in a general dictionary should be understood to have the same meaning in the context of the relevant technology, and unless otherwise explicitly defined, such term should not be interpreted as having an idealized or overly formal meaning.

Regardless of the figure number, the same or corresponding elements will be assigned the same reference numbers, and the same or corresponding elements will not be described again. Throughout the description of the present invention, when the description of a certain related conventional technology is determined to be irrelevant to the viewpoint of the present invention, the relevant detailed description will be omitted. Terms such as "first" and "second" may be used to describe various elements, but the elements described above should not be limited by the above terms. The above terms are only used to distinguish one element from another element. In the drawings, some elements may be exaggerated, omitted, or briefly illustrated, and the sizes of elements do not necessarily reflect the actual sizes of the elements.

In the following, certain embodiments of the invention will be explained in detail with reference to the accompanying drawings.

Figure 1 shows a printed circuit board according to an embodiment of the invention.

Referring to FIG. 1 , a printed circuit board according to an embodiment of the present invention includes a first insulation layer 110 , a second insulation layer 120 , a first circuit 210 , a second circuit 220 and a third circuit 230 .

The first insulating layer 110 is a layer that has insulating properties and is mainly made of insulating material. The first insulation layer 110 may be made of a rigid material with little flexibility. Example For example, epoxy resin, phenolic resin or bismaleimide triazine (BT) resin can be used as the rigid material. Epoxy resins may be (but are not limited to), for example: naphthalene epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, novolac epoxy resin, cresol novolac epoxy resin, rubber modified epoxy resin, cyclic aliphatic epoxy resin, silicone epoxy resin, nitrogen epoxy resin or phosphorus epoxy resin.

The first insulation layer 110 may be a prepreg (PPG) containing fiber reinforcement (such as fiberglass fabric). The first insulating layer 110 may be a laminated film filled with inorganic filler such as silicon dioxide. Ajinomoto Build-up Film (ABF) can be used as this build-up film.

The second insulating layer 120 is a layer that has insulating properties and is mainly made of insulating material. The second insulating layer 120 is stacked on the first insulating layer 110, in which case the first insulating layer 110 and the second insulating layer 120 are bonded to each other.

The second insulation layer 120 may be made of a flexible material with high flexibility. Polyimide (PI), liquid crystal polymer (LCP), etc. can be used as the flexible material.

The first circuit 210 , the second circuit 220 and the third circuit 230 are used for transmitting electrical signals and may be made of copper (Cu), palladium (Pd), aluminum (Al), nickel (Ni), titanium (Ti), gold ( It is made of metals such as Au), platinum (Pt), or an alloy of some of these metals in consideration of the conductivity of these metals.

The first circuit 210, the second circuit 220, and the third circuit 230 may each be made of conductive wiring, and the conductive wiring may be provided in plural numbers.

The first circuit 210 is formed on the lower surface of the first insulation layer 110 and embedded in the first insulation layer 110 . Since the first circuit 210 is embedded in the first insulating layer 110, all other parts of the first circuit 210 except the lower surface of the first circuit 210 (ie, the surface of the first circuit 210 placed on the lower side in FIG. 1) The outer surfaces are all in contact with the first insulating layer 110 . At the same time, the lower surface of the first circuit 210 may be located further inside the lower surface of the first insulation layer 110 .

The second circuit 220 is formed on the lower surface of the second insulation layer 120 and embedded in the first insulation layer 110 . The upper surface of the second circuit 220 (that is, the surface of the second circuit 220 placed on the upper side in FIG. 1 ) is in contact with the lower surface of the second insulating layer 120 , and the second circuit 220 is in contact with the lower surface of the second circuit 220 except for the second circuit 220 . All surfaces other than the upper surface are in contact with the first insulating layer 110 .

The third circuit 230 is formed on the upper surface of the second insulation layer 120 . The third circuit 230 is in contact with the upper surface of the second insulation layer 120 and protrudes from the upper surface of the second insulation layer 120 to outside the second insulation layer 120 .

The pitch of the second circuit 220 is smaller than the pitch of the first circuit 210 . In addition, the width of the second circuit 220 may be smaller than the width of the first circuit 210 , and the space of the second circuit 220 may be smaller than the space of the first circuit 210 .

Here, the "pitch" of a circuit may refer to the distance between the centers of the conductors that make up the circuit. Additionally, the "width" of a circuit may refer to the width of the conductors that make up the circuit, and the "space" of a circuit may refer to the separation distance between the conductors that make up the circuit (e.g., the distance between the opposite inner sides of each conductor). distance).

In addition, the pitch of the third circuit 230 may be smaller than the pitch of the first circuit 210 . The width of the third circuit 230 may be smaller than the width of the first circuit 210 , and the space of the third circuit 230 may be smaller than the space of the first circuit 210 .

For example, the pitch of the second circuit 220 and the pitch of the third circuit 230 may each be about 20 microns, and the pitch of the first circuit 210 may be greater than this pitch.

In other words, the second circuit 220 and the third circuit 230 may be formed denser than the first circuit 210 . In addition, the second circuit 220 and the third circuit 230 may be formed more precisely than the first circuit 210 .

Referring to FIG. 1 , the printed circuit board according to the embodiment of the present invention may further include a first via 310 and a second via 320 .

The first via 310 is a conductive structure that penetrates the first insulating layer 110 to electrically connect the first circuit 210 and the second circuit 220 . The second via 320 is a conductive structure that penetrates the second insulation layer 120 to electrically connect the second circuit 220 and the third circuit 230 .

The melting point of the first via 310 may be lower than the melting point of the first circuit 210 . The first via 310 may be made of conductive paste. Here, the conductive paste may be a paste containing metal, or a paste made of conductive polymer but not containing any metal. The metal contained in the paste may be one or more of silver (Ag), tin (Sn), nickel (Ni) and copper (Cu). In an example, first circuit 210 may be primarily made of copper, and first via 310 may be primarily made of tin. This example of conductive paste is filled in the via and then metallized through a reflow process or a heating/cooling process to become the first via 310 .

The cross-sectional area of the first via 310 may increase from the lower surface of the first insulating layer 110 to the upper surface of the first insulating layer 110 , in which case the longitudinal cross-section of the first via 310 may be in the shape of an inverted trapezoid.

The first circuit 210 may include a first pad 410 , and the first pad 410 may be formed on a lower surface of the first insulating layer 110 to be embedded in the first insulating layer 110 , similar to the first circuit 210 . The first pad 410 may be formed at an end portion of the wire constituting the first circuit 210 . The thickness of the first pad 410 may be substantially the same as the thickness of the first circuit 210 , and the width of the first pad 410 may be greater than the width of the first circuit 210 , and the cross-section of the first pad 410 may be nearly circular. of.

The first via 310 may be in contact with the first pad 410 . Specifically, the lower surface of the first via 310 may be in contact with the upper surface of the first pad 410 .

The melting point of the second passage 320 may be higher than the melting point of the first passage 310 . For example, the second via 320 may be primarily made of copper, and the first via 310 may be primarily made of tin. In addition, the second via 320 may be a plated via formed by plating.

The second via 320 may penetrate the second insulation layer 120 from the upper surface to the lower surface of the second insulation layer 120 . The cross-sectional area of the second via 320 may, but is not limited to, first decrease and then increase from the upper surface toward the lower surface of the second insulation layer 120 .

The second circuit 220 may include second pads 420 , and the second pads 420 may be formed on the lower surface of the second insulating layer 120 to be embedded in the first insulating layer 110 , similar to the second circuit 220 . The second pad 420 may be formed at an end portion of the wire constituting the second circuit 220 . The thickness of the second pad 420 may be substantially the same as the thickness of the second circuit 220 , and the width of the second pad 420 may be greater than the width of the second circuit 220 , and the cross-section of the second pad 420 may be nearly circular. of.

The first via 310 may be in contact with the second pad 420 . Specifically, the upper surface of the first via 310 may be in contact with the lower surface of the second pad 420 . In addition, the second pass The path 320 can be in contact with the second pad 420 . Specifically, the lower surface of the second via 320 may be in contact with the upper surface of the second pad 420 .

The third circuit 230 may include third pads 430 , and the third pads 430 may be formed on the upper surface of the second insulation layer 120 to protrude outward, similar to the third circuit 230 . The third pad 430 may be formed at an end portion of the wire constituting the third circuit 230 . The thickness of the third pad 430 may be substantially the same as the thickness of the third circuit 230 , and the width of the third pad 430 may be greater than the width of the third circuit 230 , and the cross-section of the third pad 430 may be nearly circular. of.

The second via 320 may be in contact with the third pad 430 . Specifically, the upper surface of the second via 320 may be in contact with the lower surface of the third pad 430 .

In an example, the electrical signal can be transmitted through the following route: first circuit 210 - first pad 410 - first via 310 - second pad 420 - second circuit 220; or first circuit 210 - first pad 410 - the first via 310 - the second pad 420 - the second via 320 - the third pad 430 - the third circuit 230.

At the same time, the first pad 410 and the third pad 430 may each be coupled to the connection component 500 . The connection components 500 may be solder bumps or solder balls. Such connection components 500 are configured to electrically connect the printed circuit board and the electronic device (or external board) and to physically engage the printed circuit board and the electronic device. In other words, the printed circuit board and the electronic device (or external board) are joined to each other through the connection part 500 .

In an example, the connecting component 500 placed on the upper side of the printed circuit board (ie, the connecting component 500 coupled to the third pad 430 ) may be coupled to the electronic device, and the connecting component 500 placed on the lower side of the printed circuit board Component 500 (i.e., coupled to the first The connection component 500) of the pad 410 may be coupled to the external board. In this case, the electrical signal can be transmitted through the following route: external board - connecting component 500 - first pad 410 - first via 310 - second pad 420 - second via 320 - third pad 430 - connection Part 500 - Electronic device.

The solder resist layer 600 may be laminated on the lower surface of the first insulating layer 110 , and the solder resist layer 600 may also be laminated on the upper surface of the second insulating layer 120 . The solder resist layer 600 may be configured to protect the first circuit 210 and the third circuit 230 . At the same time, an opening (or a through hole) may be formed in the solder resist layer 600 to partially expose the first pad 410 and the third pad 430, and the connecting component 500 may be coupled in the opening.

Figure 2 shows a printed circuit board according to an embodiment of the invention.

Referring to Figure 2, a printed circuit board according to an embodiment of the present invention includes: an insulating material 100, a first insulating layer 110, a second insulating layer 120, a third insulating layer 130, a fourth insulating layer 140, a first circuit 210, a The second circuit 220 , the third circuit 230 , the fourth circuit 240 , the fifth circuit 250 and the sixth circuit 260 .

The insulating material 100 is a portion that becomes the core of the printed circuit board and supports the printed circuit board. The insulating material 100 may be made of an insulating material such as epoxy resin, and the insulating material 100 may contain a reinforcing material 100a. The reinforcement 100a may be a fiber reinforcement such as fiberglass fabric. The insulating material 100 may be part of a copper clad laminate (CCL) excluding copper foil.

The first insulating layer 110 may be laminated on one surface of the insulating material 100 . The first insulation layer 110 may be laminated on the upper surface of the insulation material 100 . In this case, the insulating material 100 may be in contact with the lower surface of the first insulating layer 110 . In addition, the second unique The insulation layer 120 may be stacked on the first insulation layer 110 .

At the same time, a third insulating layer 130 may be laminated on the other surface of the insulating material 100 . In this case, the insulating material 100 may be in contact with the upper surface of the third insulating layer 130 . In addition, the fourth insulation layer 140 may be stacked below the third insulation layer 130 .

The first insulating layer 110 and the third insulating layer 130 are substantially the same as each other, and the second insulating layer 120 and the fourth insulating layer 140 are substantially the same as each other, and the printed circuit board may be symmetrical about the insulating material 100 .

However, the present invention is not necessarily limited to the structure described above, and when (for example) the first insulating layer 110 and the second insulating layer 120 are stacked on the insulating material 100 and only the third insulating layer 130 is stacked on the insulating material Below 100, the printed circuit board may be asymmetrical with respect to the insulating material 100. In addition, the first insulating layer 110 and the second insulating layer 120 are stacked above the insulating material 100, and the third insulating layer 130 and the fourth insulating layer 140 are stacked below the insulating material, but the first insulating layer 110 and the third insulating layer 130 The second insulating layer 120 and the fourth insulating layer 140 may be substantially different from each other (in terms of material or thickness).

In the following, the first insulating layer 110, the second insulating layer 120, the third insulating layer 130 and the fourth insulating layer 140 will be further explained. However, since the first insulating layer 110 and the second insulating layer 120 have been described above with reference to FIG. 1 , the first insulating layer 110 and the second insulating layer 120 will not be described again herein.

The third insulating layer 130 is a layer that has insulating properties and is mainly made of insulating material. The third insulating layer 130 may be made of a rigid material with little flexibility. For example, epoxy resin, phenolic resin or BT resin can be used as the rigid material. Epoxy The resin may be (but is not limited to), for example: naphthalene epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, novolac epoxy resin, cresol novolak epoxy resin, rubber modified epoxy resin Oxygen resin, cyclic aliphatic epoxy resin, silicone epoxy resin, nitrogen epoxy resin or phosphorus epoxy resin.

The third insulation layer 130 may be a prepreg (PPG) containing fiber reinforcement, such as fiberglass fabric. The third insulating layer 130 may be a laminated film filled with inorganic filler such as silicon dioxide. Ajinomoto laminated film (ABF) can be used as this laminated film.

The fourth insulating layer 140 is a layer that has insulating properties and is mainly made of insulating material. The fourth insulation layer 140 may be made of a flexible material with high flexibility. Polyimide (PI), liquid crystal polymer (LCP), etc. can be used as the flexible material.

The first circuit 210, the second circuit 220, the third circuit 230, the fourth circuit 240, the fifth circuit 250 and the sixth circuit 260 are used to transmit electrical signals, and can be made of copper (Cu), palladium (Pd), aluminum ( It is made of metals such as Al, nickel (Ni), titanium (Ti), gold (Au), platinum (Pt), etc., or is made of alloys of some of these metals in consideration of the conductivity of these metals.

The first circuit 210, the second circuit 220, the third circuit 230, the fourth circuit 240, the fifth circuit 250, and the sixth circuit 260 may each be made of conductive wiring, and the conductive wiring may be provided in plurality.

The first circuit 210 is formed on the lower surface of the first insulation layer 110 and embedded in the first insulation layer 110 . Since the first circuit 210 is embedded in the first insulating layer 110, all parts of the first circuit 210 except the lower surface of the first circuit 210 (ie, the first circuit 210 All surfaces of the path 210 (other than the surface placed on the lower side in FIG. 2 ) are in contact with the first insulating layer 110 .

In addition, the first circuit 210 is formed on one surface (ie, the upper surface) of the insulating material 100 .

The second circuit 220 is formed on the lower surface of the second insulation layer 120 and embedded in the first insulation layer 110 . The upper surface of the second circuit 220 (that is, the surface of the second circuit 220 placed on the upper side in FIG. 2 ) is in contact with the lower surface of the second insulating layer 120 , and all other parts of the second circuit 220 except for the second circuit 220 All surfaces other than the upper surface are in contact with the first insulating layer 110 .

The third circuit 230 is formed on the upper surface of the second insulation layer 120 . The third circuit 230 is in contact with the upper surface of the second insulation layer 120 and protrudes from the upper surface of the second insulation layer 120 to outside the second insulation layer 120 .

The pitch of the second circuit 220 is smaller than the pitch of the first circuit 210 . In addition, the width of the second circuit 220 may be smaller than the width of the first circuit 210 , and the space of the second circuit 220 may be smaller than the space of the first circuit 210 .

In addition, the pitch of the third circuit 230 may be smaller than the pitch of the first circuit 210 . The width of the third circuit 230 may be smaller than the width of the first circuit 210 , and the space of the third circuit 230 may be smaller than the space of the first circuit 210 .

For example, the pitch of the second circuit 220 and the pitch of the third circuit 230 may each be about 20 microns, and the pitch of the first circuit 210 may be greater than this pitch.

In other words, the second circuit 220 and the third circuit 230 may be formed denser than the first circuit 210 . In addition, the second circuit 220 and the third circuit 230 may be formed to be One circuit 210 precision.

The fourth circuit 240 is formed on the other surface (ie, the lower surface) of the insulating material 100 and embedded in the third insulating layer 130 . Since the fourth circuit 240 is embedded in the third insulating layer 130, the fourth circuit 240 except the upper surface of the fourth circuit 240 (ie, the surface of the fourth circuit 240 placed on the upper side in FIG. 2) The surfaces are all in contact with the third insulating layer 130 .

The fifth circuit 250 is formed on the lower surface of the third insulation layer 130 and embedded in the third insulation layer 130 . All surfaces of the fifth circuit 250 except the lower surface of the fifth circuit 250 (ie, the surface of the fifth circuit 250 placed on the lower side in FIG. 2 ) are in contact with the third insulating layer 130 . The fifth circuit 250 is located on one surface (ie, the upper surface) of the fourth insulating layer 140 .

The sixth circuit 260 is formed on the other surface (ie, the lower surface) of the fourth insulating layer 140 . The sixth circuit 260 is in contact with the lower surface of the fourth insulating layer 140 and protrudes outward from the other surface (ie, the lower surface) of the fourth insulating layer 140 .

The pitch of the fifth circuit 250 is smaller than the pitch of the fourth circuit 240 . In addition, the width of the fifth circuit 250 may be smaller than the width of the fourth circuit 240 , and the space of the fifth circuit 250 may be smaller than the space of the fourth circuit 240 .

In addition, the pitch of the sixth circuit 260 may be smaller than the pitch of the fourth circuit 240 . The width of the sixth circuit 260 may be smaller than the width of the fourth circuit 240 , and the space of the sixth circuit 260 may be smaller than the space of the fourth circuit 240 .

For example, the pitch of the fifth circuit 250 and the pitch of the sixth circuit 260 may each be about 20 microns, and the pitch of the fourth circuit 240 may be greater than this pitch.

In other words, the fifth circuit 250 and the sixth circuit 260 may be formed denser than the fourth circuit 240 . In addition, the fifth circuit 250 and the sixth circuit 260 may be formed more precisely than the fourth circuit 240 .

The first circuit 210 and the fourth circuit 240 may be symmetrical to each other, the second circuit 220 and the fifth circuit 250 may be symmetrical to each other, and the third circuit 230 and the sixth circuit 260 may be symmetrical to each other.

Referring to FIG. 2 , the printed circuit board according to the embodiment of the present invention may further include a through via 100 b, a first via 310 , a second via 320 , a third via 330 and a fourth via 340 .

The through via 100b penetrates the insulating material 100 to electrically connect the first circuit 210 and the fourth circuit 240. The through via 100b may be a plated via and may be made of the same metal as the first circuit 210. The through passage 100b may penetrate the insulating material 100 from one surface to another surface of the insulating material 100, and the cross-sectional area of the through passage 100b may first decrease and then increase from one surface toward the other surface of the insulating material 100. . The upper surface of the through via 100b may be in contact with the first pad 410 of the first circuit 210, and the lower surface of the through via 100b may be in contact with the fourth pad 440 of the fourth circuit 240.

The first via 310 is a conductive structure configured to electrically connect the first circuit 210 and the second circuit 220 by penetrating the first insulation layer 110 . In addition, the second via 320 is a conductive structure configured to electrically connect the second circuit 220 and the third circuit 230 by penetrating the second insulation layer 120 .

The melting point of the first via 310 may be lower than the melting point of the first circuit 210 . first pass Path 310 may be made of conductive paste. Here, the conductive paste may be a paste containing metal, or a paste made of conductive polymer but not containing any metal. The metal contained in the paste may be one or more of silver (Ag), tin (Sn), nickel (Ni) and copper (Cu). In an example, first circuit 210 may be primarily made of copper, and first via 310 may be primarily made of tin. This example of conductive paste is filled in the via and then metallized through a reflow process or a heating/cooling process to become the first via 310 .

The cross-sectional area of the first via 310 may increase from the lower surface of the first insulating layer 110 to the upper surface of the first insulating layer 110 , in which case the longitudinal cross-section of the first via 310 may be in the shape of an inverted trapezoid.

The first circuit 210 may include a first pad 410 , and the first pad 410 may be formed on a lower surface of the first insulating layer 110 to be embedded in the first insulating layer 110 , similar to the first circuit 210 . The first pad 410 may be formed at an end portion of the wire constituting the first circuit 210 . The thickness of the first pad 410 may be substantially the same as the thickness of the first circuit 210 , and the width of the first pad 410 may be greater than the width of the first circuit 210 , and the cross-section of the first pad 410 may be nearly circular. of.

The first via 310 may be in contact with the first pad 410 . Specifically, the lower surface of the first via 310 may be in contact with the upper surface of the first pad 410 . In addition, as mentioned above, the through via 100b may be in contact with the first pad 410.

The melting point of the second passage 320 may be higher than the melting point of the first passage 310 . For example, the second via 320 may be primarily made of copper, and the first via 310 may be primarily made of tin. In addition, the second via 320 may be a plated via formed by plating.

The second via 320 can penetrate from the upper surface to the lower surface of the second insulation layer 120 second insulating layer 120. The cross-sectional area of the second via 320 may, but is not limited to, first decrease and then increase from the upper surface toward the lower surface of the second insulation layer 120 .

The second circuit 220 may include second pads 420 , and the second pads 420 may be formed on the lower surface of the second insulating layer 120 to be embedded in the first insulating layer 110 , similar to the second circuit 220 . The second pad 420 may be formed at an end portion of the wire constituting the second circuit 220 . The thickness of the second pad 420 may be substantially the same as the thickness of the second circuit 220 , and the width of the second pad 420 may be greater than the width of the second circuit 220 , and the cross-section of the second pad 420 may be nearly circular. of.

The first via 310 may be in contact with the second pad 420 . Specifically, the upper surface of the first via 310 may be in contact with the lower surface of the second pad 420 . In addition, the second via 320 may be in contact with the second pad 420 . Specifically, the lower surface of the second via 320 may be in contact with the upper surface of the second pad 420 .

The third circuit 230 may include third pads 430 , and the third pads 430 may be formed on the upper surface of the second insulation layer 120 to protrude outward, similar to the third circuit 230 . The third pad 430 may be formed at an end portion of the wire constituting the third circuit 230 . The thickness of the third pad 430 may be substantially the same as the thickness of the third circuit 230 , and the width of the third pad 430 may be greater than the width of the third circuit 230 , and the cross-section of the third pad 430 may be nearly circular. of.

The second via 320 may be in contact with the third pad 430 . Specifically, the upper surface of the second via 320 may be in contact with the lower surface of the third pad 430 .

The third via 330 is a conductive structure configured to electrically connect the fourth circuit 240 and the fifth circuit 250 by penetrating the third insulating layer 130 . In addition, the fourth channel 340 is a conductive structure configured to electrically connect the fifth circuit 250 and the sixth circuit 260 by penetrating the fourth insulating layer 140 .

The melting point of the third via 330 may be lower than the melting point of the fourth circuit 240 . The third via 330 may be made of conductive paste. Here, the conductive paste may be a paste containing metal, or a paste made of conductive polymer but not containing any metal. The metal contained in the paste may be one or more of silver (Ag), tin (Sn), nickel (Ni) and copper (Cu). In an example, the fourth circuit 240 may be primarily made of copper, and the third via 330 may be primarily made of tin. This example of conductive paste is filled in the via and then metallized through a reflow process or a heating/cooling process to become the third via 330 .

The cross-sectional area of the third via 330 may increase from the upper surface to the lower surface of the fourth insulation layer 140 . In this case, the longitudinal section of the third passage 330 may have a trapezoidal shape.

The fourth circuit 240 may include fourth pads 440 , which may be formed on the lower surface of the insulating material 100 to be embedded in the third insulating layer 130 , similar to the fourth circuit 240 . The fourth pad 440 may be formed at an end portion of the wire constituting the fourth circuit 240 . The thickness of the fourth pad 440 may be substantially the same as the thickness of the fourth circuit 240 , and the width of the fourth pad 440 may be greater than the width of the fourth circuit 240 , and the cross-section of the fourth pad 440 may be nearly circular. of.

The third via 330 may be in contact with the fourth pad 440 . Specifically, the upper surface of the third via 330 may be in contact with the lower surface of the fourth pad 440 . In addition, as mentioned above, the through via 100b may be in contact with the fourth pad 440.

The melting point of the fourth passage 340 may be higher than the melting point of the third passage 330 . For example That is, the fourth via 340 may be mainly made of copper, and the third via 330 may be mainly made of tin. In addition, the fourth via 340 may be a plated via formed by plating.

The fourth via 340 may penetrate the fourth insulation layer 140 from the upper surface to the lower surface of the fourth insulation layer 140 . The cross-sectional area of the fourth via 340 may, but is not limited to, first decrease and then increase from the upper surface of the fourth insulating layer 140 toward the lower surface.

The fifth circuit 250 may include fifth pads 450 , and the fifth pads 450 may be formed on the lower surface of the third insulating layer 130 to be embedded in the third insulating layer 130 , similar to the fifth circuit 250 . The fifth pad 450 may be formed at an end portion of the wire constituting the fifth circuit 250 . The thickness of the fifth pad 450 may be substantially the same as the thickness of the fifth circuit 250 , and the width of the fifth pad 450 may be greater than the width of the fifth circuit 250 , and the cross-section of the fifth pad 450 may be nearly circular. of.

The third via 330 may be in contact with the fifth pad 450 . Specifically, the lower surface of the third via 330 may be in contact with the upper surface of the fifth pad 450 . In addition, the fourth via 340 may be in contact with the fifth pad 450 . Specifically, the upper surface of the fourth via 340 may be in contact with the lower surface of the fifth pad 450 .

The sixth circuit 260 may include sixth pads 460 , and the sixth pads 460 may be formed on the lower surface of the fourth insulation layer 140 to protrude outward, similar to the sixth circuit 260 . The sixth pad 460 may be formed at an end portion of the wire constituting the sixth circuit 260 . The thickness of the sixth pad 460 may be substantially the same as the thickness of the sixth circuit 260 , and the width of the sixth pad 460 may be greater than the width of the sixth circuit 260 , and the cross-section of the sixth pad 460 may be nearly circular. of.

The fourth via 340 may be in contact with the sixth pad 460 . Specifically, the fourth pass The lower surface of the path 340 may be in contact with the upper surface of the sixth pad 460 .

In an example, the electrical signal may be transmitted through the following route: sixth circuit 260 - sixth pad 460 - fourth via 340 - fifth pad 450 - third via 330 - fourth pad 440 - through via 100b - th A pad 410 - first via 310 - second pad 420 - second via 320 - third pad 430 - third circuit 230.

At the same time, the third pad 430 and the sixth pad 460 may each be coupled to the connection component 500 . The connection components 500 may be solder bumps or solder balls. Such connection component 500 is configured to electrically connect the printed circuit board and the electronic device (or external board) and to physically engage the printed circuit board and the electronic device. In other words, the printed circuit board and the electronic device (or external board) are joined to each other through the connection part 500 .

In an example, the connecting component 500 placed on the upper side of the printed circuit board (ie, the connecting component 500 coupled to the third pad 430 ) may be coupled to the electronic device, and the connecting component 500 placed on the lower side of the printed circuit board Component 500 (ie, connection component 500 coupled to sixth pad 460) may be coupled to the external board. In this case, the electrical signal can be transmitted through the following route: external board - connecting component 500 - sixth pad 460 - fourth via 340 - fifth pad 450 - third via 330 - fourth pad 440 - through Via 100b - first pad 410 - first via 310 - second pad 420 - second via 320 - third pad 430 - connecting component 500 - electronic device.

The solder resist layer 600 may be laminated on the lower surface of the fourth insulating layer 140 , and the solder resist layer 600 may also be laminated on the upper surface of the second insulating layer 120 . The solder resist layer 600 may be configured to protect the sixth circuit 260 and the third circuit 230 . At the same time, an opening (or through hole) may be formed in the solder resist layer 600 to partially expose the sixth pad 460 and the third pad 430, and a connection component 500 may be coupled in the opening.

Figure 3 shows a printed circuit board according to an embodiment of the invention.

Referring to Figure 3, a printed circuit board according to an embodiment of the present invention includes an insulating material 100, a first insulating layer 110, a second insulating layer 120, a third insulating layer 130, a fourth insulating layer 140, a first circuit 210, a second The circuit 220 , the third circuit 230 , the fourth circuit 240 , the fifth circuit 250 and the sixth circuit 260 may further include through vias 100 b and integrated vias 350 and 360 .

Insulating material 100, first insulating layer 110, second insulating layer 120, third insulating layer 130, fourth insulating layer 140, first circuit 210, second circuit 220, third circuit 230, fourth circuit 240, fifth The circuit 250, the sixth circuit 260 and the through-via 100b have been described above and therefore will not be described again herein.

The integrated via 350 is electrically connected to the first circuit 210 and integrally penetrates the first insulation layer 110 and the second insulation layer 120 . In addition, the integrated via 360 is electrically connected to the fourth circuit 240 and integrally penetrates the third insulating layer 130 and the fourth insulating layer 140 .

The melting point of the integrated via 350 and the integrated via 360 may be lower than the melting point of the first circuit 210 (or the fourth circuit 240). The integrated vias 350 and 360 can be made of conductive paste. Here, the conductive paste may be a paste containing metal, or a paste made of conductive polymer but not containing any metal. The metal contained in the paste may be one or more of silver (Ag), tin (Sn), nickel (Ni) and copper (Cu). In an example, the first circuit 210 may be mainly made of copper, and the integrated vias 350 and 360 may be mainly made of tin. This example of conductive paste is filled in the via and then metallized through a reflow process or a heating/cooling process to become an integrated via 350. Integrated pathway 360.

The integrated via 350 is the first via 310 and the second via 320 described with reference to FIGS. 1 and 2 that are integrated together, but do not have pads. In addition, the integrated via 360 is the third via 330 and the fourth via 340 integrated together, but does not have a pad.

The integrated vias 350 and 360 can extend to the opening of the solder resist layer 600 . In addition, the integrated vias 350 and 360 can be coupled to the connecting component 500 without the presence of pads between the integrated vias 350 and 360 and the connecting component 500 .

4 and 5 illustrate a method of manufacturing a printed circuit board according to an embodiment of the present invention.

FIG. 4 illustrates the steps of forming the second circuit 220 , the third circuit 230 and the second via 320 on or in the second insulating layer 120 , and FIG. 5 illustrates the use of various components prepared in FIG. 4 ( (hereinafter referred to as "unit substrate") to manufacture a printed circuit board.

Referring to step (a) in FIG. 4 , a through hole VH1 is formed in the substrate in which the metal layer M1 is laminated on both surfaces of the second insulating layer 120 .

As mentioned above, the second insulation layer 120 may be made of a flexible material such as polyimide. The second insulating layer 120 has been described in detail above and therefore will not be described again herein. The metal layer M1 may be made of the same metal as the second circuit 220 and the third circuit 230 . Metal layer M1 can be used as a seed layer.

The through hole VH1 penetrates both the metal layer M1 and the second insulation layer 120 . The through hole VH1 may be formed using, for example, a laser drill, or if necessary, the second insulating layer 120 may be laser drilled after partially removing the metal layer M1 using, for example, etching. _CO2 lasers can be used as laser drills.

The cross-sectional area of the through hole VH1 may first decrease and then increase from one surface of the second insulation layer 120 to the other surface. Specifically, in the case of using a laser drill to form a through hole, the cross-sectional area of the hole may be largest at the surface where the laser is incident. Therefore, the shape of the through hole VH1 shown in step (a) of FIG. 4 can be formed by irradiating laser on both one surface and the other surface of the second insulation layer 120 . However, the present invention is not necessarily limited to this shape. Different from the shape shown in step (a) of FIG. 4 , the cross-sectional area of the through hole may be constant, continuously decreasing, or always increasing from one surface of the second insulating layer 120 to another surface.

Referring to step (b) in FIG. 4, a plating layer may be formed within the through hole VH1. The plating layer may be formed only within the through hole VH1, or may be formed not only within the through hole VH1 but also on the surface of the metal layer M1. The plating layer may be made of the same metal as the metal layer M1. Although an interface may be formed between the plating layer and the metal layer M1, the interface is not shown in FIG. 4 .

Referring to step (c) in FIG. 4 , circuits are formed on both surfaces of the second insulating layer 120 . The second circuit 220 is formed on one surface (ie, the lower surface) of the second insulating layer 120, and the third circuit 230 is formed on the other surface (ie, the upper surface) of the second insulating layer 120. At the same time, the second pad 420 is formed together with the second circuit 220 , and the third pad 430 is formed together with the third circuit 230 .

The second circuit 220 and the third circuit can be formed using roll-to-roll equipment through subtractive technology or tenting technology. 230. In the case where the plating layer is only formed in the through hole VH1, the metal layer M1 is etched to form the second circuit 220 and the third circuit 230. In the case where the plating layer is formed not only within the through hole VH1 but also on the surface of the metal layer M1 , the metal layer M1 and the plating layer are etched together to form the second circuit 220 and the third circuit 230 .

In the case where the circuit is formed by the subtractive technology or the capped hole technology, the circuits can each have a precise pitch, and the manufacturing cost of the circuit can be reduced. Meanwhile, when a circuit is formed using a subtractive technology or a capped hole technology, the sides of the circuit may be inclined, and the cross-sectional area of each of the circuits may be reduced outward.

Referring to step (a) in Figure 5, a first circuit 210 is formed. The first circuit 210 may be formed through subtractive technology, capped hole technology, SAP (semi-additive process) technology or MSAP (modified semi-additive process) technology.

Specifically, a detach core (or carrier) D is provided, and the first circuit 210 is formed on one surface of the detach core D.

The detachable core D is a final detachable substrate, on which metal layers can be formed on both surfaces of the insulating material layer. In addition, the metal layers may each include a carrier metal layer and a seed metal layer S, wherein the carrier metal layer is stacked on the insulating material layer and the seed metal layer S is stacked on the carrier metal layer. The thickness of the carrier metal layer may be smaller than the thickness of the seed metal layer S. In step (a), FIG. 5 only shows the seed metal layer S and not the carrier metal layer.

One of the advantages of using knockdown cores is that two PCBs can be manufactured simultaneously. That is, as illustrated in step (a) of FIG. 5 , in addition to one surface of the disassembly core D, the first circuit 210 may also be formed on another surface of the disassembly core D. The same or similar circuit. In this case, the carrier metal layer and the seed metal layer S are laminated on both surfaces of the disassembly core D.

The first circuit 210 may be formed by forming a plating layer on the seed metal layer S and then selectively etching the plating layer corresponding to the resist pattern according to the subtractive technology or the capping technology. Furthermore, according to SAP technology or MSAP technology, the first circuit 210 may be formed by selectively plating the seed metal layer S corresponding to the pattern of the plating resist.

The first pad 410 can also be formed using the same technology as the first circuit 210 .

Referring to step (b) in FIG. 5 , the first insulating layer 110 is laminated on the disassembly core D. The first insulation layer 110 covers the first circuit 210 . The first insulating layer 110 may be stacked on one surface of the detachable core D, and an insulating layer that is the same as or similar to the first insulating layer 110 may also be stacked on the other surface of the detachable core D.

A through hole VH2 is formed in the first insulation layer 110 to partially expose the first pad 410 . A laser drill can be used to form via VH2. _CO2 lasers can be used as laser drills. The cross-sectional area of the through hole VH2 may be reduced inward.

Referring to step (c) in Figure 5, conductive paste P is filled into the through hole VH2. Conductive paste can be squeezed into via VH2. The melting point of the conductive paste P may be lower than the melting point of the first circuit 210 .

Referring to step (d) in FIG. 5 , the unit substrate manufactured through the steps illustrated in FIG. 4 is laminated on the first insulating layer 110 . The second pad 420 of the unit substrate may be positioned on the upper surface of the conductive paste P.

The unit substrate can be pressurized and laminated on the first insulating layer 110 in a high temperature environment. And the pressurization may be performed at a temperature higher than the melting point of the conductive paste P and lower than the melting point of the first circuit 210 . In this case, only the conductive paste P is melted, but the first circuit 210 and the second circuit 220 are not melted, and the conductive paste P is hardened to become the first via 310 during cooling. In a series of steps, the conductive paste P is used as an adhesive for the first circuit 210 and the second circuit 220 .

In addition, through the steps shown in (d) of FIG. 5 , the second circuit 220 and the second pad 420 are embedded in the first insulating layer 110 . To this end, when the step shown in (d) of FIG. 5 is started, the first insulating layer 110 may be in the B phase.

Referring to step (e) in Figure 5, remove the disassembly core D. The disassembly core D may be removed by first removing portions other than the seed metal layer S and then etching away the seed metal layer S. Specifically, after first separating the carrier metal layer and the seed metal layer S from each other and then leaving the seed metal layer S where it will become part of the printed circuit board, it is removed by a separate step, that is, etching. Seed metal layer S. When the seed metal layer S is etched, the lower surface of the first circuit 210 (ie, the surface on one side of the disassembly core) may be partially etched.

Referring to step (f) in FIG. 5 , the solder resist layer 600 is laminated on the first insulating layer 110 and the second insulating layer 120 , and a through hole VH3 is formed in the solder resist layer 600 . The through hole VH3 can be formed through a photolithography process, which includes exposure and development. The through hole VH3 may expose part of the first pad 410 and part of the third pad 430 .

Referring to step (g) in FIG. 5 , a connection component 500 (such as a solder bump or a solder ball) is coupled into the via VH3 . The connecting component 500 can be coupled with the first pad 410 and the third pad 430 .

Figure 6 illustrates a method of manufacturing a printed circuit board according to an embodiment of the invention. The method shown in FIG. 6 is another method of manufacturing a printed circuit board using the unit substrate manufactured through the steps shown in FIG. 4 .

Referring to step (a) in FIG. 6 , an insulating material 100 (for example, a double-sided copper-clad laminate) with a metal layer M2 laminated on both surfaces is provided, and a through hole VH4 is formed in the insulating material. The via hole VH4 may be formed using, for example, a laser drill.

Referring to step (b) in FIG. 6 , a through passage 100b is formed in the through hole VH4. In addition, the first circuit 210 and the fourth circuit 240 are formed on the surface of the insulating material 100 . The first pad 410 and the fourth pad 440 are also formed simultaneously with the first circuit 210 and the fourth circuit 240 .

Referring to step (c) in FIG. 6 , the first insulating layer 110 and the third insulating layer 130 are laminated on the insulating material 100 , and through holes VH5 and through holes are formed in the first insulating layer 110 and the third insulating layer 130 respectively. Hole VH5'.

Referring to step (d) in FIG. 6 , the conductive paste P is filled into the through hole VH5, and the conductive paste P' is filled into the through hole VH5'. The conductive paste P and conductive paste P’ can be squeezed into the through hole VH5 and the through hole VH5’. The melting point of the conductive paste P and the conductive paste P' may be lower than the melting point of the first circuit 210 (or the fourth circuit 240).

Referring to step (e) in FIG. 6 , the unit substrate is stacked on each of the first insulating layer 110 and the third insulating layer 130 . The unit substrate can be manufactured through the steps shown in FIG. 4 . The first insulating layer 110 may be stacked together with the unit substrate including the second insulating layer 120 , and the third insulating layer 130 may be stacked together with the unit substrate including the fourth insulating layer 140 . When the unit substrates are stacked, the second pad 420 corresponds to the conductive Electrical paste P, and the fifth pad 450 corresponds to the conductive paste P'.

The unit substrate can be stacked on each of the first insulating layer 110 and the third insulating layer 130 under high temperature environment, and the pressure can be higher than the melting point of the conductive paste P and the conductive paste P' and lower than The temperature of the first circuit 210 (or the fourth circuit 240) is the melting point. In this case, only the conductive paste P and the conductive paste P' are melted, but the first circuit 210 (or the fourth circuit 240) is not melted, and the conductive paste P is hardened during cooling to become the first via 310, And during the cooling period, the conductive paste P′ is hardened to form the third via 330 .

In addition, the second circuit 220 is embedded in the first insulation layer 110 , and the fifth circuit 250 is embedded in the third insulation layer 130 .

Referring to step (f) in FIG. 6 , the solder resist layer 600 is laminated on each of the second insulating layer 120 and the fourth insulating layer 140 , and a through hole VH6 is formed in the solder resist layer 600 . The through hole VH6 can be formed through a photolithography process, which includes exposure and development. The through hole VH6 may expose part of the third pad 430 and part of the sixth pad 460 .

Referring to step (g) in FIG. 6 , a connection component 500 (such as a solder bump or a solder ball) may be coupled within the via VH6 . The connecting component 500 can be coupled with the third pad 430 and the sixth pad 460 . The connection component 500 may be formed by inserting solder material into the through hole VH6 and then performing a reflow process.

7 and 8 illustrate a method of manufacturing a printed circuit board according to an embodiment of the present invention.

FIG. 7 illustrates formation of a unit substrate different from that shown in FIG. 4 . steps, and FIG. 8 shows a step of manufacturing a printed circuit board using the unit substrate prepared through the steps shown in FIG. 7 .

Referring to FIG. 7 , the second circuit 220 and the third circuit 230 are formed on the second insulation layer 120 , and the through hole VH7 is formed in the second insulation layer 120 . No via is used to fill via VH7.

Step (a) in FIG. 8 is the same as step (a) in FIG. 6 , and step (b) in FIG. 8 is the same as step (b) in FIG. 6 .

Referring to steps (c) and (d) in FIG. 8 , the first insulating layer 110 and the third insulating layer 130 are laminated on both surfaces of the insulating material 100 , and the first insulating layer 110 and the third insulating layer are respectively The through hole VH5 and the through hole VH5' are formed in the layer 130. The first insulating layer 110 and the third insulating layer 130 , each including the metal layer M3 , may first be laminated on the insulating material 100 , and then may be formed by, for example, etching after the via holes VH5 and VH5 ′ are formed. Remove metal layer M3.

Referring to step (e) in FIG. 8 , the unit substrate is stacked on each of the first insulating layer 110 and the third insulating layer 130 . Here, the through hole VH7 formed in the second insulating layer 120 corresponds to the through hole VH5 formed in the first insulating layer 110 , and the through hole VH7 ′ formed in the fourth insulating layer 140 corresponds to the through hole VH7 ′ formed in the third insulating layer 110 . Via hole VH5' in insulating layer 130.

Referring to step (f) in FIG. 8 , a solder resist layer 600 is formed on each of the second insulating layer 120 and the fourth insulating layer 140 , and then the solder resist layer 600 is formed to expose the third pad 430 and the opening of the sixth pad 460 , conductive paste P is integrally filled in the through hole VH5 , the through hole VH7 and the opening of the solder resist layer 600 . In addition, it will The conductive paste is integrally filled in the through hole VH5', the through hole VH7' and the openings of the solder resist layer 600. The integrally filled conductive paste is melted and then cooled to form integrated vias 350 and 360 .

Referring to step (g) in FIG. 8 , connecting components 500 (such as solder bumps or balls) are coupled to integrated vias 350 , 360 .

Although the present invention includes specific examples, it will be understood by those skilled in the art that various changes in form and details can be made in these examples without departing from the spirit and scope of the claimed scope and equivalents thereof. The examples set forth herein should be considered illustrative only and not for purposes of limitation. Descriptions of features or aspects in each instance should be deemed to apply to similar features or aspects in other instances. This may be achieved if the techniques are performed in a different order, and/or if components in the systems, architectures, devices or circuits are combined in a different manner and/or are replaced or supplemented by other components or their equivalents. suitable results. Therefore, the scope of the present invention is defined not by the detailed description, but by the patented scope and its equivalents, and all changes within the scope of the patented scope and its equivalents should be understood to include in the present invention.

110‧‧‧First insulation layer

120‧‧‧Second insulation layer

210‧‧‧First Circuit

220‧‧‧Second circuit

230‧‧‧Third circuit

310‧‧‧First Avenue

320‧‧‧Second Access

410‧‧‧First pad

420‧‧‧Second pad

430‧‧‧Third pad

500‧‧‧Connecting parts

600‧‧‧Solder mask

Claims (18)

A printed circuit board includes: a first insulating layer; a second insulating layer stacked on the first insulating layer; a first circuit formed on the lower surface of the first insulating layer and embedded in the first insulating layer. in the insulating layer; a second circuit formed on the lower surface of the second insulating layer and stacked in the first insulating layer; and a third circuit formed on the upper surface of the second insulating layer, wherein The second insulating layer includes a flexible material that is more flexible than a material of the first insulating layer, the flexible material includes at least one of polyimide and a liquid crystal polymer, and each of the The pitch of the second circuit and the third circuit is smaller than the pitch of the first circuit. The printed circuit board according to claim 1, wherein the third circuit protrudes outward on the upper surface of the second insulating layer. The printed circuit board according to item 1 of the patent application, wherein the first insulating layer is made of rigid material. The printed circuit board according to item 1 of the patent application further includes: a first via penetrating the first insulating layer and configured to electrically connect the first circuit and the second circuit; and Two vias, penetrating the second insulating layer and configured to electrically connect the third the second circuit and the third circuit. According to the printed circuit board of claim 4, the melting point of the first via is lower than the melting point of the first circuit. According to the printed circuit board of claim 4, the melting point of the first via is lower than the melting point of the second via. The printed circuit board according to claim 4, wherein the first pad is coupled to the lower surface of the first via, wherein the second pad is coupled to the lower surface of the second via, and the third pad is coupled to the lower surface of the second via. A pad is coupled to an upper surface of the second via, wherein the first pad and the second pad are embedded in the first insulating layer, and wherein the third pad is removed from the second via The upper surface protrudes outward. According to the printed circuit board of claim 7, the connecting component is coupled to each of the first pad and the third pad. The printed circuit board according to item 1 of the patent application further includes a solder resist layer laminated on the lower surface of the first insulating layer and the upper surface of the second insulating layer. superior. The printed circuit board according to item 1 of the patent application further includes an insulating material laminated on the lower surface of the first insulating layer, wherein the first circuit is located on the insulating material. On the surface. According to the printed circuit board described in item 10 of the patent application, the insulating material contains a reinforcing material. The printed circuit board according to item 10 of the patent application further includes: a third insulating layer laminated on the lower surface of the insulating material and made of rigid material; and a fourth insulating layer laminated on the lower surface of the insulating material. Three insulating layers are on the lower surface and are made of flexible material. The printed circuit board according to item 12 of the patent application further includes: a fourth circuit formed on the lower surface of the insulating material to be embedded in the third insulating layer; and a fifth circuit formed on one surface of the fourth insulating layer to be embedded in the third insulating layer, wherein the pitch of the fifth circuit is smaller than the pitch of the fourth circuit. The printed circuit board according to claim 13 of the patent application further includes a sixth circuit formed on another surface of the fourth insulating layer to protrude outward so as to be positioned with the The fifth circuit is opposite, wherein the pitch of the sixth circuit is smaller than the pitch of the fourth circuit. The printed circuit board according to claim 13 of the patent application further includes a through-via that penetrates the insulating material to electrically connect the first circuit and the fourth circuit. The printed circuit board according to item 12 of the patent application further includes a solder resist layer laminated on the upper surface of the second insulating layer and the on the lower surface of the fourth insulating layer. The printed circuit board according to claim 10 of the patent application further includes a via, the via integrally penetrating the first insulating layer and the second insulating layer to be electrically connected to the first circuit. According to the printed circuit board of claim 17, the melting point of the via is lower than the melting point of the first circuit.