Electronic apparatus comprising interconnected printed circuit boards and manufacturing method therefor

Abstract

This electronic apparatus may comprise: a first printed circuit board (PCB) including a conductive pad; a second PCB including a conductive pad and coupled to a portion of the first PCB; and a conductive connection part disposed between the conductive pad of the first PCB and the conductive pad of the second PCB. The conductive connection part may include: a first portion containing a first solder material and bonded to the conductive pad of the first PCB; and a second portion containing a second solder material different from the first solder material, formed on the conductive pad of the second PCB, and electrically connected to the first portion of the conductive connection part. The first portion of the conductive connection part may be thicker than the second portion of the conductive connection part.

Description

Electronic device including mutually bonded printed circuit boards and method of manufacturing the same

[0001] The present disclosure relates to an electronic device comprising mutually bonded printed circuit boards and a method for manufacturing the same.

[0002] An electronic device may include a printed circuit board (PCB) on which various components are arranged. The PCB may be connected to another PCB. For example, the PCB may be bonded to the other PCB without a connector including a plug and a receptacle. For example, the PCB and the other PCB may be bonded by placing a pad portion of the other PCB on a pad portion of the PCB and then applying pressure and heating.

[0003] The information described above may be provided as related art for the purpose of aiding understanding of the present disclosure. No claim or determination is made as to whether any of the foregoing may be applied as prior art in relation to the present disclosure.

[0004] According to one embodiment, an electronic device may include: a first printed circuit board (PCB) including a conductive pad; a second PCB including a conductive pad and coupled to a portion of the first PCB; and a conductive connection portion disposed between the conductive pad of the first PCB and the conductive pad of the second PCB. The conductive connection portion may include a first portion formed of a first solder material and attached to the conductive pad of the first PCB; and a second portion formed of a second solder material different from the first solder material, formed on the conductive pad of the second PCB, and electrically connected to the first portion of the conductive connection portion. The first portion of the conductive connection portion may be thicker than the second portion of the conductive connection portion.

[0005] In one embodiment, a method for manufacturing a PCB assembly comprising the first PCB, the second PCB, the conductive connection portion, and the non-conductive material may include the steps of attaching a solder ball formed of the first solder material to the conductive pad of the first PCB and attaching a self-aligning film to the second PCB so as to cover the conductive pad of the second PCB. The self-aligning film may include the second solder material and the non-conductive material. The method for manufacturing the PCB assembly may include the steps of aligning the first PCB with the solder ball attached and the second PCB with the self-aligning film attached so that the conductive pad of the first PCB and the conductive pad of the second PCB are aligned; and joining the first PCB and the second PCB that are aligned with each other.

[0006] According to one embodiment, a printed circuit board assembly may include: a first printed circuit board including a conductive pad; a second PCB including a conductive pad and coupled to a portion of the first PCB; and a conductive connection portion disposed between the conductive pad of the first PCB and the conductive pad of the second PCB. The conductive connection portion may include a first portion formed of a first solder material and attached to the conductive pad of the first PCB; and a second portion formed of a second solder material different from the first solder material, formed on the conductive pad of the second PCB, and electrically connected to the first portion of the conductive connection portion. The first portion of the conductive connection portion may be thicker than the second portion of the conductive connection portion.

[0007] FIG. 1a is a drawing showing a printed circuit board assembly of an electronic device according to one embodiment.

[0008] Figure 1b is a drawing showing the joints of PCB assemblies.

[0009] FIG. 2 is a drawing showing a printed circuit board assembly of an electronic device according to one embodiment.

[0010] FIG. 3a is a drawing showing a conductive connection according to one embodiment.

[0011] FIG. 3b is an image showing a conductive connection according to one embodiment.

[0012] FIG. 4 is a flowchart illustrating a method for manufacturing a PCB assembly according to one embodiment.

[0013] FIGS. 5A, FIGS. 5B, and FIGS. 5C are drawings for explaining a method of manufacturing a PCB assembly according to one embodiment.

[0014] FIG. 6 is a drawing for explaining a method of manufacturing a PCB assembly according to one embodiment.

[0015] FIG. 7 is a block diagram of an electronic device in a network environment according to various embodiments.

[0016] Hereinafter, embodiments of the present disclosure are described in detail with reference to the drawings so that those skilled in the art can easily practice them. However, the present disclosure may be embodied in various different forms and is not limited to the embodiments described herein. In relation to the description of the drawings, the same or similar reference numerals may be used for identical or similar components. Furthermore, in the drawings and related descriptions, descriptions of well-known functions and configurations may be omitted for clarity and brevity.

[0017] In the following, redundant descriptions of configurations having the same reference numeral shown in different drawings may not be repeated, and descriptions thereof may be applied identically, similarly, or in a corresponding manner unless otherwise noted. In descriptions referring to specific drawings below, reference numerals of other drawings may be referenced.

[0018] FIG. 1a is a drawing showing a printed circuit board assembly of an electronic device according to one embodiment. FIG. 1b is a drawing showing a joint of PCB assemblies.

[0019] Referring to FIG. 1a, according to one embodiment, the electronic device (e.g., the electronic device (701) of FIG. 7) may include a PCB assembly (10). The PCB assembly (10) may include a first PCB (100) and a second PCB (200). The first PCB (100) may be coupled to the second PCB (200). For example, the first PCB (100) may include a pad portion (101), and the second PCB (200) may include a pad portion (201) coupled to the pad portion (101) of the first PCB (100). For example, the pad portion (101) of the first PCB (100) may be bonded to the pad portion (201) of the second PCB (200). The pad portion (101) and the pad portion (201) may each be referred to as a coupling portion, a bonding portion, or a connecting portion.

[0020] In one embodiment, the electronic device may include various types of devices. For example, the electronic device may include a portable communication device such as a smartphone, a wearable device such as an electronic watch, an electronic ring, electronic glasses, or a head-mounted display (HMD), or an audio output device such as headphones, a headset, earphones, earbuds, or a speaker, but is not limited thereto. For example, the electronic device may include a computer device, a portable multimedia device, a portable medical device, a camera, or a home appliance.

[0021] In one embodiment, the second PCB (200) may be the main board of the electronic device. For example, an application processor of the electronic device (e.g., the processor (720) of FIG. 7) may be placed on the second PCB (200). An electronic component (105) may be placed on the first PCB (100). Unlike in the illustration, the electronic component (105) may be connected to the first PCB (100) through a connector placed on the first PCB (100). The electronic component (105) may be electrically connected to the second PCB (200) through the first PCB (100). For example, the electronic component (105) may be electrically connected to the application processor of the electronic device through the first PCB (100) and the second PCB (200). The electronic component (105) may include, for example, at least some of the components shown in FIG. 7. For example, the electronic component (105) may include an antenna module (e.g., the antenna module (797) of FIG. 7). For example, the electronic component (105) may include a mmWave antenna module.

[0022] For non-limiting examples, the first PCB (100) and / or the second PCB (200) may be a package substrate on which one or more semiconductor chips are mounted. For non-limiting examples, the first PCB (100) and / or the second PCB (200) may be a package substrate of a system in package (SIP) or a system on package (SOP).

[0023] Below, the bonding structure of the pad portion (101) of the first PCB (100) and the pad portion (201) of the second PCB (200) is described.

[0024] Referring to FIG. 1b, according to one embodiment, the first PCB (100) (or pad portion (101)) may include a surface (100A) facing the direction (e.g., -Z direction) of the second PCB (200) (or pad portion (201)). The Z axis shown in FIG. 1b may be a direction substantially perpendicular to the pad portion (101) of the first PCB (100) and the pad portion (201) of the second PCB (200).

[0025] The first PCB (100) may include a conductive pad (110) formed on a surface (100A) and / or defining a portion of the surface (100A). For example, the conductive pad (110) may be formed on a substrate of the first PCB (100). The substrate of the first PCB (100) may include one or more dielectric layers. The conductive pad (110) may define a portion of the surface (100A) of the first PCB (100), and the substrate of the first PCB (100) may define another portion of the surface (100A) corresponding to the periphery of the conductive pad (110). The other portion of the surface (100A) formed by the substrate of the first PCB (100) may be referred to as a non-conductive region of the first PCB (100). The conductive pad (110) may be formed of, for example, an electrically conductive material. For example, the conductive pad (110) can be formed of a metal such as copper, and is not limited to that.

[0026] The second PCB (200) (or pad portion (201)) may include a surface (200A) oriented in the direction (e.g., +Z direction) of the first PCB (100) (or pad portion (101)). The second PCB (200) may include a conductive pad (210) formed on the surface (200A) and / or defining a portion of the surface (200A). For example, the conductive pad (210) may be formed on a substrate of the second PCB (200). The substrate of the second PCB (200) may include one or more dielectric layers. The conductive pad (210) may define a portion of the surface (200A) of the second PCB (200), and the substrate of the second PCB (200) may define another portion of the surface (200A) corresponding to the periphery of the conductive pad (210). The other portion of the surface (200A) formed by the above-mentioned substrate of the second PCB (200) may be referred to as a non-conductive region of the second PCB (200). The conductive pad (210) may be formed, for example, of an electrically conductive material. For example, but not limited to, the conductive pad (210) may be formed of a metal such as copper.

[0027] In one embodiment, the first PCB (100) and / or the second PCB (200) may include an RPCB (rigid PCB), an FPCB (flexible PCB), or an RFPCB (rigid-flexible PCB).

[0028] For example, the substrate of the first PCB (100) and / or the substrate of the second PCB (200) may be formed rigidly, at least partially. As a non-limiting example, the substrate of the first PCB (100) and / or the substrate of the second PCB (200) may be formed at least partially from an epoxy-based resin such as FR4 (flame retardant 4), glass, or ceramic.

[0029] For example, the substrate of the first PCB (100) and / or the substrate of the second PCB (200) may be formed to be at least partially flexible (or bendable). As a non-limiting example, the substrate of the first PCB (100) and / or the substrate of the second PCB (200) may be formed at least partially from a flexible resin such as polyimide.

[0030] According to one embodiment, the PCB assembly (10) may include a conductive connection (300) and a non-conductive material (400).

[0031] A conductive connection part (300) may be disposed between a conductive pad (110) of a first PCB (100) and a conductive pad (210) of a second PCB (200). A conductive connection part (300) may be attached to the first conductive pad (110) and the second conductive pad (210). A conductive connection part (300) may electrically connect the first conductive pad (110) and the second conductive pad (210), and may structurally and / or mechanically combine the first conductive pad (110) and the second conductive pad (210).

[0032] The non-conductive material (400) may include a resin such as epoxy. The non-conductive material (400) may at least partially fill the space between the surface (100A) of the first PCB (100) and the surface (200A) of the second PCB (200) so as to surround the conductive connection (300). For example, the non-conductive material (400) may include a fillet portion attached to the conductive connection (300).

[0033] A non-conductive material (400) may be attached to the first PCB (100), the second PCB (200), and the conductive connection (300). For example, the non-conductive material (400) may be attached to the other part of the surface (100A) of the first PCB (100) (e.g., formed by the substrate of the first PCB (100)), the other part of the surface (200A) of the second PCB (200) (e.g., formed by the substrate of the second PCB (200)), and the side of the conductive connection (300) (e.g., the surfaces (310A and 320A) of FIG. 3A). For example, the non-conductive material (400) may wrap the conductive connection (300). For example, the non-conductive material (400) may seal the conductive connection (300). The non-conductive material (400) can improve the bonding strength between the first PCB (100) and the second PCB (200). The non-conductive material (400) may be referred to as a non-conductive connection or a non-conductive adhesive.

[0034] In one embodiment, the pad portion (101) of the first PCB (100) may include a plurality of first conductive pads, and the pad portion (201) of the second PCB (200) may include a plurality of second conductive pads each connected to the plurality of first conductive pads through a plurality of conductive connections. Each of the plurality of first conductive pads may include a conductive pad (110). Each of the plurality of second conductive pads may include a conductive pad (210). Each of the plurality of conductive connections may include a conductive connection (300). A non-conductive material (400) may be at least partially filled in the space between the surface (100A) of the first PCB (100), the surface (200A) of the second PCB (200), and the plurality of conductive connections so as to surround each of the plurality of conductive connections. A non-conductive material (400) can be attached to the surface (100A) of the first PCB (100), the surface (200A) of the second PCB (200), and the plurality of conductive connections.

[0035] The plurality of first conductive pads of the first PCB (100) may be spaced apart from each other. The pitch of the plurality of first conductive pads of the first PCB (100) (e.g., distance between the centers of adjacent pads) may be about 0.43 mm or less. The pitch of the plurality of first conductive pads of the first PCB (100) may be about 0.4 mm or less. The pitch of the plurality of first conductive pads of the first PCB (100) may be about 0.35 mm or less. The pitch of the plurality of first conductive pads of the first PCB (100) may be about 0.3 mm or less.

[0036] The plurality of second conductive pads of the second PCB (200) may be spaced apart from each other. The pitch of the plurality of second conductive pads of the second PCB (200) (e.g., distance between the centers of adjacent pads) may be about 0.43 mm or less. The pitch of the plurality of second conductive pads of the second PCB (200) may be about 0.4 mm or less. The pitch of the plurality of second conductive pads of the second PCB (200) may be about 0.35 mm or less. The pitch of the plurality of second conductive pads of the second PCB (200) may be about 0.3 mm or less.

[0037] FIG. 2 is a drawing showing a printed circuit board assembly of an electronic device according to one embodiment.

[0038] Referring to FIG. 2, according to one embodiment, the first PCB (100) may further include a non-conductive layer (120) formed on the substrate of the first PCB (100). The non-conductive layer (120) may form a part of the surface (100A), and the conductive pad (110) may form another part of the surface (100A). The non-conductive layer (120) may be referred to as a solder resist, a solder resist layer, a solder mask, a solder mask layer, an insulating layer, or a protective layer.

[0039] In one embodiment, the non-conductive layer (120) may define an opening (or opening region) in which a conductive pad (110) is located at least partially. For example, the conductive pad (110) may be an SMD (solder mask defined) pad whose edges are covered by the non-conductive layer (120). For example, the conductive pad (110) of the first PCB (100) may define a portion of the surface (100A) of the first PCB (100), and the non-conductive layer (120) may define another portion of the surface (100A) that surrounds (and / or extends from) said portion of the surface (100A) of the first PCB (100).

[0040] In one embodiment, the conductive pad (110) of the first PCB (100) may include a first portion (111) and a second portion (112) protruding from the first portion (111). The first portion (111) of the conductive pad (110) may be an example of the conductive pad (110) of FIG. 1B. The second portion (112) may protrude from the center of the first portion (111) in the direction of the second PCB (200) (or pad portion (201)) (e.g., -Z direction). The second portion (112) of the conductive pad (110) may penetrate a part of the conductive connection portion (300) (e.g., the first portion (310) of FIG. 3A).

[0041] When the conductive pad (110) includes a first portion (111) and does not include a second portion (112), the edge portion of the first portion (111) of the conductive pad (110) is covered by a non-conductive layer (120), thereby reducing the bonding area between the conductive connection (300) and the conductive pad (110). The second portion (112) of the conductive pad (110) penetrates the said portion of the conductive connection (300), thereby increasing the bonding area between the conductive pad (110) and the conductive connection (300). Accordingly, the bonding strength between the conductive pad (110) and the conductive connection (300) can be improved. In terms of the second portion (112) protruding from the first portion (111), the second portion (112) may be referred to as a protruding portion of the conductive pad (110).

[0042] According to one embodiment, the second PCB (200) may further include a non-conductive layer (220) formed on the substrate of the second PCB (200). The non-conductive layer (220) may form a part of the surface (200A), and the conductive pad (210) may form another part of the surface (200A). The non-conductive layer (220) may be referred to as a solder resist, a solder resist layer, a solder mask, a solder mask layer, an insulating layer, or a protective layer.

[0043] In one embodiment, the non-conductive layer (220) may define an opening (or opening region) in which a conductive pad (210) is located at least partially. For example, the conductive pad (210) may be an SMD pad whose edges are covered by the non-conductive layer (220). For example, the conductive pad (210) of the second PCB (200) may define a portion of the surface (200A) of the second PCB (200), and the non-conductive layer (220) may define another portion of the surface (200A) that surrounds (and / or extends from) said portion of the surface (200A) of the second PCB (200).

[0044] In one embodiment, the conductive pad (210) of the second PCB (200) may include a first portion (211) and a second portion (212) protruding from the first portion (211). The first portion (211) of the conductive pad (210) may be an example of the conductive pad (210) of FIG. 1B. The second portion (212) may protrude from the center of the first portion (211) in the direction of the first PCB (100) (or pad portion (101)) (e.g., +Z direction). The second portion (212) of the conductive pad (210) may penetrate a part of the conductive connection portion (300) (e.g., the second portion (320) of FIG. 3A).

[0045] When the conductive pad (210) includes a first portion (211) and does not include a second portion (212), the edge portion of the first portion (211) of the conductive pad (210) is covered by a non-conductive layer (220), thereby reducing the bonding area between the conductive connection (300) and the conductive pad (210). The second portion (212) of the conductive pad (210) penetrates the said portion of the conductive connection (300), thereby increasing the bonding area between the conductive pad (210) and the conductive connection (300). Accordingly, the bonding strength between the conductive pad (210) and the conductive connection (300) can be improved. In terms of the second portion (212) protruding from the first portion (211), the second portion (212) may be referred to as a protruding portion of the conductive pad (210).

[0046] A non-conductive material (400) may be placed between the non-conductive layer (120) of the first PCB (100) and the non-conductive layer (220) of the second PCB (200) so as to surround the conductive connection (300). The non-conductive material (400) may be attached to the non-conductive layer (120) of the first PCB (100), the non-conductive layer (220) of the second PCB (200), and the sides (e.g., surfaces (310A and 320A)) of the conductive connection (300).

[0047] The non-conductive layer (120) of the first PCB (100) may define a plurality of first openings, and each of the plurality of first pads may be located within a corresponding opening among the plurality of first openings. The non-conductive layer (220) of the second PCB (200) may define a plurality of second openings, and each of the plurality of second pads may be located within a corresponding opening among the plurality of second openings. A non-conductive material (400) may be disposed between the surface (100A) of the first PCB (100) and the surface (200A) of the second PCB (200) so as to surround each of the plurality of connections.

[0048] Alternatively, the PCB assembly (10) may not include a non-conductive layer (120) of the first PCB (100) and / or a non-conductive layer (220) of the second PCB (200).

[0049] FIG. 3a is a drawing showing a conductive connection according to one embodiment. FIG. 3b is an image showing a conductive connection according to one embodiment.

[0050] Referring to FIGS. 3a and 3b, according to one embodiment, a conductive connection portion (300) may include a first portion (310) and a second portion (320) electrically connected to the first portion (310). The first portion (310) may be formed on a conductive pad (110) of a first PCB (100), and the second portion (320) may be formed on a conductive pad (210) of a second PCB (200). For example, the first portion (310) may be attached to the conductive pad (110) of the first PCB (100), and the second portion (320) may be attached to the conductive pad (210) of the second PCB (200).

[0051] A first portion (310) of the conductive connection (300) may be formed of a first solder material, and a second portion (320) of the conductive connection (300) may be formed of a second solder material different from the first solder material. For example, the melting point of the first solder material may be higher than the melting point of the second solder material. For example, the melting point of the first solder material may be about 217 degrees Celsius, and the melting point of the second solder material may be about 138 degrees Celsius. For example, the first solder material may include tin-silver-copper (SAC) solder. For example, the SAC solder may include SAC305 (Sn-3.0Ag-0.5Cu). The second solder material may include low temperature solder (LTS). For example, but not limited to, the above LTS may include a tin-bismuth (Sn-Bi) alloy (e.g., Sn-58Bi) or a tin-bismuth-silver (Sn-Bi-Ag) alloy.

[0052] The volume of the first portion (310) of the conductive connection (300) may be larger than the volume of the second portion (320) of the conductive connection (300). For example, the thickness (T1) of the first portion (310) of the conductive connection (300) may be thicker than the thickness (T2) of the second portion (320) of the conductive connection (300). The thicknesses (T1 and T2) may be lengths along a direction substantially perpendicular to the pad portion (101) of the first PCB (100) and / or the pad portion (201) of the second PCB (200) (e.g., the Z-axis). For example, the thicknesses (T1 and T2) may be lengths based on a direction perpendicular to the pad portion (101) of the first PCB (100) and / or the pad portion (201) of the second PCB (200) and passing through the center of the pad portion (101) of the first PCB (100) and / or the center of the pad portion (201) of the second PCB (200). For example, the first portion (310) of the conductive connection (300) may be larger than the width of the second portion (320) of the conductive connection (300). The widths may be lengths along a direction perpendicular to the Z-axis.

[0053] A first portion (310) of the conductive connection (300) may include a surface (310A) in contact with a portion of the non-conductive material (400). A second portion (320) of the conductive connection (300) may include a surface (320A) in contact with another portion of the non-conductive material (400).

[0054] The surface (310A) of the first part (310) of the conductive connection (300) may include a portion having a convex cross-sectional shape (e.g., convex toward the non-conductive material (400)). The surface (320A) of the second part (320) of the conductive connection (300) may include a portion having a concave cross-sectional shape (e.g., sunken toward the center of the conductive connection (300)). For example, though not limited to, the area of ​​the surface (310A) of the first part (310) in contact with the said portion of the non-conductive material (400) may be larger than the area of ​​the surface (320A) of the second part (320) in contact with the said other portion of the non-conductive material (400).

[0055] In one embodiment, the first portion (310) of the conductive connection (300) may have a first microstructure, and the second portion (320) of the conductive connection (300) may have a second microstructure different from the first microstructure. For example, the first microstructure may include a Sn-rich phase. For example, the second microstructure of the second portion (320) of the conductive connection (300) may include a lamellar structure of a Bi-rich phase.

[0056] Unlike in the city, the first part (310) of the conductive connection part (300) can be attached to the conductive pad (210) of the second PCB (200), and the second part (320) of the conductive connection part (300) can be attached to the conductive pad (110) of the first PCB (100). This may vary depending on which of the PCBs (100 and 200) the solder ball (501) and self-aligning film (502), which will be described later, are attached to.

[0057] A conductive connection part (300) comprising a first part (310) formed of the first solder material and a second part (320) formed of the second solder material different from the first solder material can be referred to as a hybrid solder.

[0058] The conductive connection portion (300) may include an interface (or interface layer) (330) between the first portion (310) and the second portion (320). The interface (330) may be formed from a material (or alloy material) formed by mixing the first solder material of the first portion (310) and the second solder material of the second portion (320). The thickness (and / or volume) of the interface (330) may vary depending on the temperature during the bonding of the first PCB (100) and the second PCB (200) described later. For example, the thickness (and / or volume) of the interface (330) may increase as the temperature during the bonding of the first PCB (100) and the second PCB (200) described later increases.

[0059] FIG. 4 is a flowchart illustrating a method for manufacturing a PCB assembly according to one embodiment. FIG. 5a, FIG. 5b, and FIG. 5c are drawings for explaining a method for manufacturing a PCB assembly according to one embodiment.

[0060] Referring to FIG. 4, in step (410), a solder ball formed of a first solder material may be attached to a conductive pad of the first PCB. For example, referring to FIG. 5a and FIG. 5b, a solder ball (501) formed of the first solder material may be attached to a conductive pad (110) of the first PCB (100). For example, the solder ball (501) may be soldered to a conductive pad (110) of the first PCB (100).

[0061] Referring to FIG. 4, in step (420), a self-aligning film may be attached to the second PCB. For example, referring to FIG. 5a and FIG. 5b, a self-aligning film (502) may be attached to the surface (200A) of the second PCB (200). For example, the self-aligning film (502) may be attached to the surface (200A) of the second PCB (200) to cover the conductive pad (210) of the second PCB (200). For example, the self-aligning film (502) may be temporarily attached to the second PCB (200) by applying heat and pressure. The self-aligning film (502) may include the second solder material, a non-conductive material (e.g., a non-conductive material (400)), and a flux (or solder flux). For example, referring to FIG. 5a, the self-aligning film (502) may be attached to the substrate and conductive pad (210) of the second PCB (200), which at least partially form the surface (200A) of the second PCB (200). For example, referring to FIG. 5b, the self-aligning film (502) may be attached to the non-conductive layer (220) and conductive pad (210) of the second PCB (200), which at least partially form the surface (200A) of the second PCB (200).

[0062] Referring to FIG. 4, in step (430), the first PCB and the second PCB can be aligned. For example, referring to FIG. 5a and FIG. 5b, the first PCB (100) and the second PCB (200) can be aligned such that the conductive pad (110) of the first PCB (100) and the conductive pad (210) of the second PCB (200) are aligned (e.g., along the Z-axis), and the self-aligning film (502) and the solder ball (501) face each other.

[0063] Referring to FIG. 4, in step (440), the first PCB and the second PCB can be bonded. For example, referring to FIG. 5a and FIG. 5b, the first PCB (100) and the second PCB (200) can be bonded by hot-pressing the first PCB (100) and the second PCB (200) that are aligned with each other. For example, the first PCB (100) and the second PCB (200) can be bonded to each other by hot-pressing the first PCB (100) and the second PCB (200) in a vertical direction (1). For example, the first PCB (100) and the second PCB (200) can be bonded to each other by being heated to a specified temperature while being pressed in a vertical direction (1). For example, the first PCB (100) and the second PCB (200) can be bonded using a hot-bar process. The specified temperature may include a temperature between the melting point of the first solder material and the melting point of the second solder material that is lower than the melting point of the first solder material. For example, the specified temperature may include about 200 degrees Celsius, but is not limited thereto.

[0064] The self-aligning film (502) can be activated by heat and pressure applied to the self-aligning film (502). For example, referring to FIG. 5c, the non-conductive material (400) and the second solder material (503) contained within the self-aligning film (502) can be melted. The melted second solder material (503) can flow within the non-conductive material (400). For example, the melted second solder material (503) can wet the surface of the solder ball (501) and the conductive pad (210). A molten second solder material (503) in contact with the surface of a solder ball (501) and a conductive pad (210) can react with the solder ball (501) and the conductive pad (210) (e.g., intermetallic diffusion), and as the molten second solder material (503) solidifies, the solder ball (501), the second solder material (503), and the conductive pad (210) can be bonded together. Accordingly, a conductive connection (300) can be formed. As the second solder material (503) hardens (or after the second solder material (503) hardens, the non-conductive material (400) hardens, and the non-conductive material (400) can be bonded to the conductive connection (300).

[0065] In step (440), the solder ball (501) may be less melted than the second solder material (503). The solder ball (501) that is less melted than the second solder material (503) may function as a stopper when the first PCB (100) and the second PCB (200) are pressed.

[0066] In a comparative example, the solder resist layers included in the first PCB (100) and the second PCB (200) can function as stoppers. For example, the solder resist layers may have a height greater than that of the conductive pads. Accordingly, even if the solder resist layer of the first PCB (100) and the solder resist layer of the second PCB (200) come into contact due to the pressure of the first PCB (100) and the second PCB (200), a space may be formed between the conductive pad (110) of the first PCB (100) and the conductive pad (210) of the second PCB (200) through which solder, flux, and non-conductive material (400) can flow. However, due to these solder resist layers, it may be difficult to reduce the pitch of the conductive pads. In one embodiment, as shown in FIG. 5a, even if the pad portion (101) of the first PCB (100) and the pad portion (201) of the second PCB (200) do not include a solder resist layer (e.g., non-conductive layers (120 and 220) of FIG. 5b), a space may be provided by the solder ball (501) through which the second solder material (503), non-conductive material (400), and flux contained within the self-aligning film (502) can flow. Accordingly, the pitch of the conductive pads can be reduced while securing the bonding strength of the first PCB (100) and the second PCB (200).

[0067] In a comparative example, when the solder resist layers perform a stopper function, a solder dam may be formed by the solder resist layer included in the first PCB (100) and the solder resist layer included in the second PCB (200) coming into contact with each other. Due to this solder dam, the space between the conductive pad (110) of the first PCB (100) and the conductive pad (210) of the second PCB (200) may become narrow. Due to this narrow space, when the first PCB (100) and the second PCB (200) are joined, a phenomenon may occur where the non-conductive material (400) pushes out the solder, and consequently, a defect in the electrical connection between the conductive pads (110 and 210) may occur.

[0068] In one embodiment, as shown in FIG. 5a, the pad portion (101) of the first PCB (100) and the pad portion (201) of the second PCB (200) do not include a solder resist layer (e.g., non-conductive layers (120 and 220) of FIG. 5b), so the solder dam may not be formed. Additionally, the solder ball (501) may provide a space for the second solder material (503), non-conductive material (400), and flux contained within the self-aligning film (502) to flow. Accordingly, the bonding strength of the first PCB (100) and the second PCB (200) and the reliability of the electrical connection may be improved.

[0069] In one embodiment, as shown in FIG. 5b, even though the pad portion (101) of the first PCB (100) and the pad portion (201) of the second PCB (200) include non-conductive layers (120 and 220), the non-conductive layers (120 and 220) can be separated from each other through a non-conductive material (400) because the solder ball (501) performs the function of a stopper. That is, the solder dam in which the non-conductive layers (120 and 220) are in contact may not be formed. Accordingly, the bonding strength of the first PCB (100) and the second PCB (200) and the reliability of the electrical connection can be improved.

[0070] In a comparative example, the first PCB (100) and the second PCB (200) can be bonded using only a self-aligning film (502) without solder balls (501). If solder balls (501) are omitted, the function of the stopper described above may be lost. Even if the function of the stopper is replaced by a solder resist layer, additional problems as described above may occur. Furthermore, due to the omission of solder balls (501), the amount of solder (e.g., the second solder material (503)) contained in the self-aligning film (502) may be insufficient to bond the first PCB (100) and the second PCB (200). A shortage of solder may reduce bonding strength and the reliability of the electrical connection. According to one embodiment, the printed circuit board assembly (10) can secure a sufficient amount of solder by using solder balls (501) and a self-aligning film (502). Accordingly, voids and bonding strength can be improved.

[0071] FIG. 6 is a drawing for explaining a method of manufacturing a PCB assembly according to one embodiment.

[0072] Referring to FIG. 6, for joining the first PCB (100) and the second PCB (200) (e.g., step (440)), a solder ball (601) and a non-conductive film (602) may be used instead of a self-aligning film (502). For example, in step (420), unlike the self-aligning film (502) being attached to the second PCB (200), a solder ball (601) may be attached to a conductive pad (210) of the second PCB (200). Subsequently, a non-conductive film (602) may be attached to a surface (200A) of the second PCB (200) so as to cover the solder ball (601). The solder ball (601) may have a lower melting point than the solder ball (501). For example, the solder ball (601) may be formed from the second solder material (e.g., LTS).

[0073] The technical problems to be solved in this disclosure are not limited to those mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art to which this disclosure belongs.

[0074] According to one embodiment, an electronic device (701) may include: a first printed circuit board (100) including a conductive pad (110); a second PCB (200) including a conductive pad (210) and coupled to a part of the first PCB (100); and a conductive connection portion (300) disposed between the conductive pad (110) of the first PCB (100) and the conductive pad (210) of the second PCB (200). The conductive connection portion (300) comprises a first portion (310) formed of a first solder material and attached to the conductive pad (110) of the first PCB (100); It may include a second part (320) formed of a second solder material different from the first solder material, formed on the conductive pad (210) of the second PCB (200), and electrically connected to the first part (310) of the conductive connection part (300). The first part (310) of the conductive connection part (300) may be thicker than the second part (320) of the conductive connection part (300).

[0075] In one embodiment, the conductive pad (110) of the first PCB (100) may define a portion of the surface (100A) of the first PCB (100). The first PCB (100) may include a non-conductive region that defines another portion of the surface (100A) of the first PCB (100). The other portion of the surface (100A) of the first PCB (100) may cover the portion of the surface (100A) of the first PCB (100). The conductive pad (210) of the second PCB (200) may define a portion of the surface (200A) of the second PCB (200). The second PCB (200) may include a non-conductive region that defines another portion of the surface (200A) of the second PCB (200). The other part of the surface (200A) of the second PCB (200) may cover the part of the surface (200A) of the second PCB (200). The electronic device (701) may include a non-conductive material (400) attached to the non-conductive region of the first PCB (100), the non-conductive region of the second PCB (200), and the conductive connection (300).

[0076] In one embodiment, the surface (310A) of the first portion (310) of the conductive connection (300) in contact with the first portion (310) of the non-conductive material (400) may have a convex cross-sectional shape. The surface (320A) of the second portion (320) of the conductive connection (300) in contact with the second portion (320) of the non-conductive material (400) may have a concave cross-sectional shape.

[0077] In one embodiment, the first PCB (100) may include a solder resist layer (120) forming the non-conductive region of the first PCB (100). The second PCB (200) may include a solder resist layer (220) forming the non-conductive region of the second PCB (200) and spaced apart from the solder resist layer (120) of the first PCB (100) through the non-conductive material (400).

[0078] In one embodiment, the first portion (310) of the conductive connection portion (300) may be larger than the width of the second portion (320) of the conductive connection portion (300).

[0079] In one embodiment, the melting point of the first solder material may be higher than the melting point of the second solder material.

[0080] In one embodiment, the first portion (310) of the conductive connection portion (300) may have a first microstructure. The second portion (320) of the conductive connection portion (300) may have a second microstructure different from the first microstructure.

[0081] In one embodiment, the conductive pad (110) of the first PCB (100) may include a protruding portion (112) that partially penetrates the first portion (310) of the conductive connection portion (300).

[0082] In one embodiment, the conductive pad (210) of the second PCB (200) may include a protruding portion (212) that partially penetrates the second portion (320) of the conductive connection portion (300).

[0083] In one embodiment, the conductive pad (110) of the first PCB (100) may be an SMD (solder mask defined) pad. The conductive pad (210) of the second PCB (200) may be an SMD pad.

[0084] In one embodiment, the first solder material may be tin-silver-copper (SAC) solder. The second solder material may be low temperature solder (LTS).

[0085] In one embodiment, the electronic device (701) may include an application processor (720) disposed on the first PCB (100); and an electronic component connected to the second PCB (200) and electrically connected to the application processor (720) through the second PCB (200) and the first PCB (100). The second PCB (200) may include a flexible PCB (FPCB).

[0086] In one embodiment, a method for manufacturing a PCB assembly (10) comprising the first PCB (100), the second PCB (200), the conductive connection portion (300), and the non-conductive material (400) may include the step (410) of attaching a solder ball (501) formed of the first solder material to the conductive pad (110) of the first PCB (100), and the step (420) of attaching a self-aligning film (502) to the second PCB (200) to cover the conductive pad (210) of the second PCB (200). The self-aligning film (502) may include the second solder material and the non-conductive material (400). The manufacturing method of the above PCB assembly (10) may include the step (430) of aligning the first PCB (100) to which the solder ball (501) is attached and the second PCB (200) to which the self-aligning film (502) is attached so that the conductive pad (110) of the first PCB (100) and the conductive pad (210) of the second PCB (200) are aligned; and the step (440) of joining the first PCB (100) and the second PCB (200) that are aligned with each other.

[0087] In one embodiment, the method for manufacturing the PCB assembly (10) may include the step (440) of joining the first PCB (100) and the second PCB (200) by hot-pressing the first PCB (100) and the second PCB (200) at a specified temperature. The specified temperature may include a temperature between a first melting point of the first solder material and a second melting point of the second solder material that is lower than the first melting point.

[0088] According to one embodiment, a printed circuit board assembly (10) may include: a first printed circuit board (100) including a conductive pad (110); a second PCB (200) including a conductive pad (210) and coupled to a part of the first PCB (100); and a conductive connection portion (300) disposed between the conductive pad (110) of the first PCB (100) and the conductive pad (210) of the second PCB (200). The conductive connection portion (300) comprises a first portion (310) formed of a first solder material and attached to the conductive pad (110) of the first PCB (100); It may include a second part (320) formed of a second solder material different from the first solder material, formed on the conductive pad (210) of the second PCB (200), and electrically connected to the first part (310) of the conductive connection part (300). The first part (310) of the conductive connection part (300) may be thicker than the second part (320) of the conductive connection part (300).

[0089] In one embodiment, the conductive pad (110) of the first PCB (100) may define a portion of the surface (100A) of the first PCB (100). The first PCB (100) may include a non-conductive region that defines another portion of the surface (100A) of the first PCB (100). The other portion of the surface (100A) of the first PCB (100) may cover the portion of the surface (100A) of the first PCB (100). The conductive pad (210) of the second PCB (200) may define a portion of the surface (200A) of the second PCB (200). The second PCB (200) may include a non-conductive region that defines another portion of the surface (200A) of the second PCB (200). The other part of the surface (200A) of the second PCB (200) may cover the part of the surface (200A) of the second PCB (200). The PCB assembly (10) may include a non-conductive material (400) attached to the non-conductive region of the first PCB (100), the non-conductive region of the second PCB (200), and the conductive connection (300).

[0090] In one embodiment, the surface (310A) of the first portion (310) of the conductive connection (300) in contact with the first portion (310) of the non-conductive material (400) may have a convex cross-sectional shape. The surface (320A) of the second portion (320) of the conductive connection (300) in contact with the second portion (320) of the non-conductive material (400) may have a concave cross-sectional shape.

[0091] In one embodiment, the first PCB (100) may include a solder resist layer (120) forming the non-conductive region of the first PCB (100). The second PCB (200) may include a solder resist layer (220) forming the non-conductive region of the second PCB (200) and spaced apart from the solder resist layer (120) of the first PCB (100) through the non-conductive material (400).

[0092] In one embodiment, the first portion (310) of the conductive connection portion (300) may be larger than the width of the second portion (320) of the conductive connection portion (300).

[0093] In one embodiment, the melting point of the first solder material may be higher than the melting point of the second solder material.

[0094] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure belongs.

[0095] FIG. 7 is a block diagram of an electronic device in a network environment according to various embodiments.

[0096] Referring to FIG. 7, in a network environment (700), an electronic device (701) may communicate with an electronic device (702) through a first network (798) (e.g., a short-range wireless communication network) or with at least one of an electronic device (704) or a server (708) through a second network (799) (e.g., a long-range wireless communication network). According to one embodiment, the electronic device (701) may communicate with the electronic device (704) through the server (708). According to one embodiment, the electronic device (701) may include a processor (720), memory (730), input module (750), sound output module (755), display module (760), audio module (770), sensor module (776), interface (777), connection terminal (778), haptic module (779), camera module (780), power management module (788), battery (789), communication module (790), subscriber identification module (796), or antenna module (797). In some embodiments, at least one of these components (e.g., connection terminal (778)) may be omitted from the electronic device (701), or one or more other components may be added. In some embodiments, some of these components (e.g., sensor module (776), camera module (780), or antenna module (797)) may be integrated into a single component (e.g., display module (760)).

[0097] The processor (720) can control at least one other component (e.g., a hardware or software component) of the electronic device (701) connected to the processor (720) by executing software (e.g., a program (740)), for example, and can perform various data processing or operations. According to one embodiment, as at least part of the data processing or operations, the processor (720) can store commands or data received from other components (e.g., a sensor module (776) or a communication module (790)) in volatile memory (732), process the commands or data stored in volatile memory (732), and store the resulting data in non-volatile memory (734). According to one embodiment, the processor (720) may include a main processor (721) (e.g., a central processing unit or an application processor) or an auxiliary processor (723) that can operate independently or together with it (e.g., a graphics processing unit, a neural processing unit (NPU), an image signal processor, a sensor hub processor, or a communication processor). For example, if the electronic device (701) includes a main processor (721) and an auxiliary processor (723), the auxiliary processor (723) may be configured to use less power than the main processor (721) or to be specialized for a designated function. The auxiliary processor (723) may be implemented separately from the main processor (721) or as part thereof.

[0098] The auxiliary processor (723) may control at least some of the functions or states associated with at least one component of the electronic device (701) (e.g., display module (760), sensor module (776), or communication module (790)) on behalf of the main processor (721) while the main processor (721) is in an inactive (e.g., sleep) state, or together with the main processor (721) while the main processor (721) is in an active (e.g., application execution) state. According to one embodiment, the auxiliary processor (723) (e.g., image signal processor or communication processor) may be implemented as part of another functionally related component (e.g., camera module (780) or communication module (790)). According to one embodiment, the auxiliary processor (723) (e.g., neural network processing unit) may include a hardware structure specialized for processing an artificial intelligence model. The artificial intelligence model may be generated through machine learning. Such learning may be performed, for example, on the electronic device (701) itself where the artificial intelligence model is executed, or through a separate server (e.g., server (708)). The learning algorithm may include, for example, supervised learning, unsupervised learning, semi-supervised learning, or reinforcement learning, but is not limited to the examples described above. The artificial intelligence model may include a plurality of artificial neural network layers.An artificial neural network may be a deep neural network (DNN), a convolutional neural network (CNN), a recurrent neural network (RNN), a restricted Boltzmann machine (RBM), a deep belief network (DBN), a bidirectional recurrent deep neural network (BRDNN), a deep Q-network, or a combination of two or more of the above, but is not limited to the examples described above. In addition to the hardware structure, the artificial intelligence model may include a software structure, either additionally or substantially.

[0099] The memory (730) can store various data used by at least one component of the electronic device (701) (e.g., processor (720) or sensor module (776)). The data may include, for example, software (e.g., program (740)) and input or output data for related commands. The memory (730) may include volatile memory (732) or non-volatile memory (734).

[0100] The program (740) may be stored as software in memory (730) and may include, for example, an operating system (742), middleware (744), or an application (746).

[0101] The input module (750) can receive commands or data to be used for a component of the electronic device (701) (e.g., processor (720)) from outside the electronic device (701) (e.g., user). The input module (750) may include, for example, a microphone, a mouse, a keyboard, a key (e.g., a button), or a digital pen (e.g., a stylus pen).

[0102] The sound output module (755) can output a sound signal to the outside of the electronic device (701). The sound output module (755) may include, for example, a speaker or a receiver. The speaker may be used for general purposes, such as multimedia playback or recording playback. The receiver may be used to receive incoming calls. According to one embodiment, the receiver may be implemented separately from the speaker or as part thereof.

[0103] The display module (760) can visually provide information to an external (e.g., user) of the electronic device (701). The display module (760) may include, for example, a display, a holographic device, or a projector and a control circuit for controlling said device. According to one embodiment, the display module (760) may include a touch sensor configured to detect a touch, or a pressure sensor configured to measure the intensity of the force generated by said touch.

[0104] The audio module (770) can convert sound into an electrical signal or, conversely, convert an electrical signal into sound. According to one embodiment, the audio module (770) can acquire sound through the input module (750) or output sound through the sound output module (755) or an external electronic device (e.g., electronic device (702)) (e.g., speaker or headphones) connected directly or wirelessly to the electronic device (701).

[0105] The sensor module (776) can detect the operating state of the electronic device (701) (e.g., power or temperature) or the external environmental state (e.g., user state) and generate an electrical signal or data value corresponding to the detected state. According to one embodiment, the sensor module (776) may include, for example, a gesture sensor, a gyroscope sensor, a barometric pressure sensor, a magnetic sensor, an accelerometer sensor, a grip sensor, a proximity sensor, a color sensor, an IR (infrared) sensor, a biosensor, a temperature sensor, a humidity sensor, or an illuminance sensor.

[0106] The interface (777) may support one or more specified protocols that can be used for the electronic device (701) to be connected directly or wirelessly to an external electronic device (e.g., electronic device (702)). According to one embodiment, the interface (777) may include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, an SD card interface, or an audio interface.

[0107] The connection terminal (778) may include a connector through which the electronic device (701) can be physically connected to an external electronic device (e.g., electronic device (702)). According to one embodiment, the connection terminal (778) may include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (e.g., a headphone connector).

[0108] The haptic module (779) can convert an electrical signal into a mechanical stimulus (e.g., vibration or movement) or an electrical stimulus that the user can perceive through tactile or kinesthetic senses. According to one embodiment, the haptic module (779) may include, for example, a motor, a piezoelectric element, or an electric stimulation device.

[0109] The camera module (780) can capture still images and video. According to one embodiment, the camera module (780) may include one or more lenses, image sensors, image signal processors, or flashes.

[0110] The power management module (788) can manage power supplied to the electronic device (701). According to one embodiment, the power management module (788) can be implemented, for example, as at least part of a power management integrated circuit (PMIC).

[0111] The battery (789) can supply power to at least one component of the electronic device (701). According to one embodiment, the battery (789) may include, for example, a non-rechargeable primary battery, a rechargeable secondary battery, or a fuel cell.

[0112] The communication module (790) can support the establishment of a direct (e.g., wired) communication channel or a wireless communication channel between an electronic device (701) and an external electronic device (e.g., electronic device (702), electronic device (704), or server (708)), and the performance of communication through the established communication channel. The communication module (790) may include one or more communication processors that operate independently of the processor (720) (e.g., application processor) and support direct (e.g., wired) communication or wireless communication. According to one embodiment, the communication module (790) may include a wireless communication module (792) (e.g., cellular communication module, short-range wireless communication module, or GNSS (global navigation satellite system) communication module) or a wired communication module (794) (e.g., LAN (local area network) communication module, or power line communication module). The corresponding communication module among these communication modules can communicate with an external electronic device (704) through a first network (798) (e.g., a short-range communication network such as Bluetooth, WiFi (wireless fidelity) direct, or IrDA (infrared data association)) or a second network (799) (e.g., a legacy cellular network, a 5G network, a next-generation communication network, the Internet, or a computer network (e.g., a LAN or WAN)). These various types of communication modules may be integrated into a single component (e.g., a single chip) or implemented as multiple separate components (e.g., multiple chips). The wireless communication module (792) can identify or authenticate the electronic device (701) within a communication network such as the first network (798) or the second network (799) using subscriber information (e.g., International Mobile Subscriber Identifier (IMSI)) stored in the subscriber identification module (796).

[0113] The wireless communication module (792) can support 5G networks and next-generation communication technologies following 4G networks, for example, new radio access technology. NR access technology can support high-speed transmission of high-capacity data (enhanced mobile broadband (eMBB)), minimization of terminal power and connection of multiple terminals (massive machine type communications (mMTC)), or high reliability and low latency (ultra-reliable and low-latency communications (URLLC)). The wireless communication module (792) can support a high-frequency band (e.g., mmWave band) to achieve a high data transmission rate, for example. The wireless communication module (792) can support various technologies for securing performance in the high-frequency band, such as beamforming, massive MIMO (multiple-input and multiple-output), full dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, or large-scale antenna. The wireless communication module (792) can support various requirements specified in the electronic device (701), external electronic device (e.g., electronic device (704)), or network system (e.g., second network (799)). According to one embodiment, the wireless communication module (792) can support a Peak data rate (e.g., 20 Gbps or more) for eMBB realization, loss coverage (e.g., 164 dB or less) for mMTC realization, or U-plane latency (e.g., downlink (DL) and uplink (UL) each 0.5 ms or less, or round trip 1 ms or less) for URLLC realization.

[0114] An antenna module (797) can transmit a signal or power to or from an external source (e.g., an external electronic device). According to one embodiment, the antenna module (797) may include an antenna comprising a radiator made of a conductor or a conductive pattern formed on a substrate (e.g., a PCB). According to one embodiment, the antenna module (797) may include a plurality of antennas (e.g., an array antenna). In this case, at least one antenna suitable for a communication method used in a communication network, such as a first network (798) or a second network (799), may be selected from the plurality of antennas, for example, by a communication module (790). A signal or power may be transmitted or received between the communication module (790) and an external electronic device through the selected at least one antenna. According to some embodiments, in addition to the radiator, other components (e.g., a radio frequency integrated circuit (RFIC)) may be additionally formed as part of the antenna module (797).

[0115] According to various embodiments, the antenna module (797) may form a mmWave antenna module. According to one embodiment, the mmWave antenna module may include a printed circuit board, an RFIC disposed on or adjacent to a first surface (e.g., bottom surface) of the printed circuit board and capable of supporting a specified high frequency band (e.g., mmWave band), and a plurality of antennas (e.g., array antennas) disposed on or adjacent to a second surface (e.g., top surface or side surface) of the printed circuit board and capable of transmitting or receiving a signal of the specified high frequency band.

[0116] At least some of the above components can be connected to each other via a communication method between peripheral devices (e.g., bus, GPIO (general purpose input and output), SPI (serial peripheral interface), or MIPI (mobile industry processor interface)) and exchange signals (e.g., commands or data) with each other.

[0117] According to one embodiment, commands or data may be transmitted or received between the electronic device (701) and an external electronic device (704) through a server (708) connected to a second network (799). Each of the external electronic devices (702, or 704) may be the same or a different type of device as the electronic device (701). According to one embodiment, all or part of the operations performed on the electronic device (701) may be performed on one or more of the external electronic devices (702, 704, or 708). For example, if the electronic device (701) needs to perform a function or service automatically or in response to a request from a user or another device, the electronic device (701) may request one or more external electronic devices to perform at least part of the function or service instead of performing the function or service itself or additionally. One or more external electronic devices that receive the above request may execute at least part of the requested function or service, or additional function or service related to the request, and transmit the result of the execution to the electronic device (701). The electronic device (701) may provide the result as is or additionally processed as at least part of the response to the request. For this purpose, for example, cloud computing, distributed computing, mobile edge computing (MEC), or client-server computing technology may be used. The electronic device (701) may provide ultra-low latency services using, for example, distributed computing or mobile edge computing. In another embodiment, the external electronic device (704) may include an Internet of Things (IoT) device. The server (708) may be an intelligent server using machine learning and / or neural networks. According to one embodiment, the external electronic device (704) or the server (708) may be included within the second network (799).The electronic device (701) can be applied to intelligent services (e.g., smart home, smart city, smart car, or healthcare) based on 5G communication technology and IoT-related technology.

[0118] The electronic device according to the various embodiments disclosed in this document may be a device of various forms. The electronic device may include, for example, a portable communication device (e.g., a smartphone), a computer device, a portable multimedia device, a portable medical device, a camera, a wearable device, or a consumer electronics device. The electronic device according to the embodiments of this document is not limited to the devices described above.

[0119] The various embodiments of this document and the terms used therein are not intended to limit the technical features described in this document to specific embodiments, and should be understood to include various modifications, equivalents, or substitutions of said embodiments. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or more of said items unless the relevant context clearly indicates otherwise. In this document, each of phrases such as "A or B," "at least one of A and B," "at least one of A or B," "A, B or C," "at least one of A, B and C," and "at least one of A, B, or C" may include any one of the items listed together in the corresponding phrase, or all possible combinations thereof. Terms such as "first," "second," or "first" or "second" may be used simply to distinguish a component from another component and do not limit the components in any other aspect (e.g., importance or order). Where any component (e.g., the first) is referred to as "coupled" or "connected" to another component (e.g., the second), with or without the terms "functionally" or "communicationally," it means that said component may be connected to said other component directly (e.g., via a wire), wirelessly, or through a third component.

[0120] The term “module” as used in the various embodiments of this document may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic block, component, or circuit, for example. A module may be a component formed integrally, or a minimum unit of said component or a part thereof that performs one or more functions. For example, according to one embodiment, a module may be implemented in the form of an application-specific integrated circuit (ASIC).

[0121] Various embodiments of the present document may be implemented as software (e.g., program (740)) comprising one or more instructions stored in a storage medium (e.g., internal memory (736) or external memory (738)) readable by a machine (e.g., electronic device (701)). For example, a processor (e.g., processor (720)) of the machine (e.g., electronic device (701)) may call at least one of the one or more instructions stored in the storage medium and execute it. This enables the machine to be operated to perform at least one function according to the at least one called instruction. The one or more instructions may include code generated by a compiler or code that can be executed by an interpreter. The storage medium readable by the machine may be provided in the form of a non-transitory storage medium. Here, 'non-temporary' simply means that the storage medium is a tangible device and does not contain a signal (e.g., electromagnetic waves), and the term does not distinguish between cases where data is stored semi-permanently and cases where it is stored temporarily.

[0122] According to one embodiment, the method according to the various embodiments disclosed herein may be provided by being included in a computer program product. The computer program product may be traded between a seller and a buyer as a product. The computer program product may be distributed in the form of a device-readable storage medium (e.g., compact disc read-only memory (CD-ROM)), or distributed online (e.g., download or upload) through an application store (e.g., Play Store™) or directly between two user devices (e.g., smartphones). In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily created on a device-readable storage medium, such as the memory of a manufacturer's server, an application store's server, or a relay server.

[0123] According to various embodiments, each component (e.g., module or program) of the components described above may include a singular or multiple entities, and some of the multiple entities may be separated and placed in other components. According to various embodiments, one or more of the components or operations among the aforementioned components may be omitted, or one or more other components or operations may be added. Generally or additionally, multiple components (e.g., module or program) may be integrated into a single component. In this case, the integrated component may perform one or more functions of each of the multiple components in the same or similar manner as those performed by the corresponding component among the multiple components prior to integration. According to various embodiments, operations performed by the module, program, or other components may be executed sequentially, in parallel, iteratively, or heuristically, or one or more of the operations may be executed in a different order, omitted, or one or more other operations may be added.

Claims

1. In an electronic device, A first PCB (printed circuit board) including conductive pads; A second PCB comprising a conductive pad and coupled to a part of the first PCB; and It includes a conductive connection portion disposed between the conductive pad of the first PCB and the conductive pad of the second PCB, and The above conductive connection is: A first portion formed of a first solder material and attached to the conductive pad of the first PCB; and A second portion formed of a second solder material different from the first solder material, formed on the conductive pad of the second PCB, and electrically connected to the first portion of the conductive connection portion, comprising The first portion of the conductive connection part is thicker than the second portion of the conductive connection part. Electronic device.

2. In Claim 1, The conductive pad of the first PCB defines a portion of the surface of the first PCB, and The first PCB includes a non-conductive region defining another part of the surface of the first PCB, and The other part of the surface of the first PCB covers the part of the surface of the first PCB, The conductive pad of the second PCB defines a portion of the surface of the second PCB, and The second PCB includes a non-conductive region defining another part of the surface of the second PCB, and The other part of the surface of the second PCB covers the part of the surface of the second PCB, The above electronic device is, A non-conductive material comprising the non-conductive region of the first PCB, the non-conductive region of the second PCB, and the conductive connection portion attached thereto. Electronic device.

3. In Claim 2, The surface of the first portion of the conductive connection part in contact with the first portion of the non-conductive material has a convex cross-sectional shape. The surface of the second portion of the conductive connection part in contact with the second portion of the non-conductive material has a concave cross-sectional shape. Electronic device.

4. In claim 2 or claim 3, The first PCB comprises a solder resist layer forming the non-conductive region of the first PCB, and The second PCB comprises a solder resist layer that forms the non-conductive region of the second PCB and is spaced apart from the solder resist layer of the first PCB through the non-conductive material. Electronic device.

5. In any one of claims 1 to 4, The first portion of the conductive connection part is larger than the width of the second portion of the conductive connection part. Electronic device.

6. In any one of claims 1 to 5, The melting point of the first solder material is higher than the melting point of the second solder material. Electronic device.

7. In any one of claims 1 to 6, The first portion of the above-mentioned conductive connection part has a first microstructure, and The second portion of the conductive connection above has a second microstructure different from the first microstructure, Electronic device.

8. In any one of claims 1 to 7, The conductive pad of the first PCB comprises a protruding portion that partially penetrates the first portion of the conductive connection portion. Electronic device.

9. In any one of claims 1 to 8, The conductive pad of the second PCB includes a protruding portion that partially penetrates the second portion of the conductive connection portion. Electronic device.

10. In claim 8 or claim 9, The conductive pad of the first PCB is an SMD (solder mask defined) pad, and The conductive pad of the second PCB is an SMD pad. Electronic device.

11. In any one of claims 1 to 10, The first solder material is a tin-silver-copper (SAC) solder, and The above second solder material is an LTS (low temperature solder), Electronic device.

12. In any one of claims 1 to 11, An application processor disposed on the first PCB; and It includes an electronic component connected to the second PCB and electrically connected to the application processor through the second PCB and the first PCB, The second PCB above includes an FPCB (flexible PCB), Electronic device.

13. A method for manufacturing a PCB assembly comprising the first PCB, the second PCB, and the conductive connection portion of any one of claims 1 to 12, wherein A step of attaching a solder ball formed of the first solder material to the conductive pad of the first PCB; A step of attaching a self-aligning film to the second PCB to cover the conductive pad of the second PCB, wherein the self-aligning film comprises the second solder material and the non-conductive material; A step of aligning the first PCB with the solder ball attached and the second PCB with the self-aligning film attached so that the conductive pad of the first PCB and the conductive pad of the second PCB are aligned; and A step comprising joining the first PCB and the second PCB aligned with each other. Manufacturing method.

14. In Claim 13, The step of bonding the first PCB and the second PCB includes the step of hot-pressing the first PCB and the second PCB at a specified temperature. The above-mentioned specified temperature includes a temperature between the first melting point of the first solder material and the second melting point of the second solder material which is lower than the first melting point. Manufacturing method.

15. In a printed circuit board assembly, A first PCB (printed circuit board) including conductive pads; A second PCB comprising a conductive pad and coupled to a part of the first PCB; and It includes a conductive connection portion disposed between the conductive pad of the first PCB and the conductive pad of the second PCB, and The above conductive connection is: A first portion formed of a first solder material and attached to the conductive pad of the first PCB; and A second portion formed of a second solder material different from the first solder material, formed on the conductive pad of the second PCB, and electrically connected to the first portion of the conductive connection portion, comprising The first portion of the conductive connection part is thicker than the second portion of the conductive connection part. PCB assembly.

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