JP2007227857A - Printed board incorporating component, printed board, electronic apparatus, and electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printed board incorporating component capable of maintaining high reliability of electronic components by preventing peeling between a resin layer and electronic components. <P>SOLUTION: The printed board incorporating the component comprises a first board, a second board, and a resin layer that fills the outer peripherals of the electronic components mounted between the first board and the second board. The electronic components are formed in such a way that their perimeters are curved shapes. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a component-embedded printed circuit board, a printed circuit board, an electronic device, and an electronic component, and in particular, a component-embedded printed circuit board on which a chip-type electronic component or the like is mounted, a printed circuit board, an electronic device, and the like. It relates to electronic components.

  2. Description of the Related Art Today, various electronic devices in various fields such as personal computers, various video / audio devices such as DVDs, and communication devices such as mobile phones are strongly required to be small and light.

  In response to this, the development of miniaturization of electronic components such as resistors and capacitors, and miniaturization technology for printed circuit boards has been promoted.

  For example, in today's electronic devices, there are many forms in which electronic components are mounted on a surface-mount printed circuit board using surface-mounted electronic components. However, as a technology for further improving the mounting density of electronic components, a built-in component type Printed circuit boards are attracting attention.

  In a component-embedded printed circuit board, chip-type electronic components such as chip resistors and chip capacitors and semiconductor ICs are embedded in a resin layer, and two or more layers are formed by pressing the printed circuit board in a sandwich from above and below the resin layer. A multilayer printed circuit board is formed. Since chip-type electronic components are built in the resin layer between printed circuit boards, high-density mounting can be achieved and the wiring distance of electronic components can be shortened, which contributes to improving electrical performance such as high-speed processing. .

On the other hand, the amount of heat generated by electronic components is also increasing. For this reason, deformation (warping) or destruction (cracking) of a thinned electronic component due to heat has become a problem. In order to cope with this problem, for example, Japanese Patent Application Laid-Open No. H10-228688 discloses a technique that can reduce the warpage of the ceramic substrate by chamfering or curving the four corners of the ceramic substrate of the IC package. It is disclosed.
Japanese Patent Application Laid-Open No. 11-265962

  As described above, in a component-embedded printed circuit board, chip-type electronic components and semiconductor ICs are embedded in a resin layer, thereby fixing these electronic components and protecting them from the outer peripheral atmosphere.

  Further, even in the case of a surface mount type printed circuit board, a form in which a resin layer for sealing the surface mount component is formed may be employed in order to increase the bonding strength of the surface mount component and protect it from the outside air. .

  In general, the thermal expansion coefficient of an electronic component is different from the thermal expansion coefficient of a resin layer covering the periphery of the electronic component. For this reason, although a thermal stress arises in an electronic component and a resin layer, stress concentration generate | occur | produces especially in the corner | angular part of the outer periphery of an electronic component. As a result, a crack or the like occurs in the resin layer in contact with the corner of the electronic component, and finally there arises a problem that peeling occurs between the electronic component and the resin layer. The peeling of the resin layer reduces the reliability of electronic components that should be protected by the resin layer.

  The present invention has been made in view of the above circumstances, and prevents the separation between the resin layer and the electronic component, and maintains the high reliability of the electronic component, printed circuit board, printed circuit board, electronic An object is to provide equipment and electronic components.

  In order to solve the above-mentioned problems, a component-embedded printed circuit board according to the present invention includes a first board, a second board, the first board, and the second board, as described in claim 1. And a resin layer filling the outer periphery of the electronic component mounted between the electronic component and the electronic component, wherein the outer peripheral shape is formed in a curved shape.

  In order to solve the above-mentioned problem, an electronic device containing a component-embedded printed board according to the present invention is the electronic device including the component-embedded printed circuit board as described in claim 4. The printed circuit board includes a first substrate, a second substrate, and a resin layer filling an outer periphery of an electronic component mounted between the first substrate and the second substrate. Is characterized in that its outer peripheral shape is curved.

  Moreover, in order to solve the said subject, the printed circuit board which concerns on this invention is provided with the board | substrate and the resin layer which seals the outer periphery of the electronic component mounted in the said board | substrate, as described in Claim 7, The electronic component is characterized in that its outer peripheral shape is a curved surface.

  Moreover, in order to solve the said subject, the electronic component which concerns on this invention is the 1st board | substrate, the 2nd board | substrate, and the said 1st board | substrate and the said 2nd board | substrate as described in Claim 10. In an electronic component incorporated in a component-embedded printed board having a resin layer filling the gap, the electronic component is formed so that its outer peripheral shape is a curved surface.

  According to the component-embedded printed circuit board, the printed circuit board, the electronic device, and the electronic component according to the present invention, the separation between the resin layer and the electronic component can be prevented, and the high reliability of the electronic component can be maintained.

  Embodiments of a component-embedded printed circuit board, a printed circuit board, an electronic device, and an electronic component according to the present invention will be described with reference to the accompanying drawings.

(1) Electronic Component FIGS. 1C and 1D are views showing an example of an external appearance of the electronic component 10 according to the first embodiment. FIG. 1C is a plan view and FIG. d) shows a side view. The electronic component according to the first embodiment is, for example, a chip-type passive electronic component 10 such as a chip-type capacitor or a chip-type resistor, and is an electronic component having two electrodes at both ends.

  On the other hand, FIGS. 1A and 1B are diagrams showing an example of the appearance of a conventional chip-type passive electronic component 100, in which FIG. 1A is a plan view and FIG. 1B is a side view. The figure is shown.

  The chip-type passive electronic component 100 has a square-shaped passive element body 102 (for example, a capacitor body or a resistor body) at the center, and a rectangular shape formed of conductive metal or the like at both ends of the passive element body 102. An electrode 101 is provided.

  The dimensions (a × b) of the chip-type passive electronic component 100 are standardized to some extent, and are, for example, 3.5 mm × 2.8 mm, 1.0 mm × 0.5 mm, 0.6 mm × 0.3 mm, and the like.

  When the chip-type passive electronic component 100 is mounted on a surface-mount type printed circuit board, the chip-type passive electronic component 100 is mounted on the printed circuit board, and the electrode pads provided on the printed circuit board and the electrodes 101 of the chip-type passive electronic component 100 are mounted. Are joined with solder paste or the like.

  Further, for the purpose of protecting the chip-type passive electronic component 100 from the outside air and the like, and for the purpose of increasing the bonding strength between the chip-type passive electronic component 100 and the printed circuit board, the chip-type passive electronic component 100 is placed on the chip-type passive electronic component 100 from above. A resin layer may be formed so as to cover the chip-type passive electronic component 100 in some cases.

  On the other hand, recently, a mounting form called a component built-in type printed circuit board has appeared. In a component built-in type printed circuit board, a resin layer is formed in a sandwich between a plurality of, for example, two printed circuit boards, and an electronic component is embedded in the resin layer.

  In the component built-in type printed circuit board, in addition to being able to mount electronic components on the outer surface of each of the two printed circuit boards, electronic components can be mounted on the inner surface (the surface facing the resin layer). For this reason, the mounting density of electronic components is improved. In addition, the wiring distance between the electronic components can be shortened, and the electrical characteristics are improved.

  By the way, in the form in which the conventional chip-type passive electronic component 100 is embedded in the resin layer of the component-embedded printed board or the form in which the chip-type passive electronic component 100 is resin-sealed, there are the following problems.

  That is, since the thermal expansion coefficient of the chip-type passive electronic component 100 and the thermal expansion coefficient of the resin layer are generally different, the thermal stress resulting from the difference between the thermal expansion coefficients of the two is in the resin layer and the chip-type passive electronic component 100. Occurs. At this time, if the outer peripheral shape of the chip-type passive electronic component 100 has a discontinuous point, such as an acute corner, a stress concentration occurs at the discontinuous point.

  As a result, a large strain is generated at the discontinuous point of the outer peripheral shape of the chip-type passive electronic component 100, and in some cases, the resin layer is broken, and peeling occurs between the resin layer and the chip-type passive electronic component 100. A problem occurs.

  Specifically, in FIG. 1A or FIG. 1B, stress concentration occurs at the corner 103 on the outer periphery of the electrode 101, and the resin layer easily peels from the vicinity of the corner 103.

  Further, stress concentration also occurs at the discontinuous point 104 at the boundary between the passive element body 102 and the electrode 103, and the resin layer easily peels from the vicinity of the discontinuous point 104.

  When peeling occurs between the chip-type passive electronic component 100 and the resin layer, the protection function for the chip-type passive electronic component 100 is lowered, and the purpose is to increase the bonding strength between the chip-type passive electronic component 100 and the printed circuit board. This cannot be achieved sufficiently, and as a result, the mounting reliability of the chip-type passive electronic component 100 is lowered.

  The point of the present invention is to eliminate as many discontinuous points in the outer peripheral shape of the chip-type passive electronic component 100 as possible, to reduce stress concentration at the discontinuous points, and to generate separation between the chip-type passive electronic component 100 and the resin layer. It is in the point to prevent.

  FIGS. 1C and 1D are views showing an example of the appearance of the chip-type passive electronic component 10 according to the embodiment of the present invention. From the above viewpoint, the discontinuous points of the outer peripheral shape are excluded. The outer peripheral shape is a curved surface.

  The basic configuration of the chip-type passive electronic component 10 according to the present embodiment includes a passive element body 12 and an electrode 11 as in the conventional chip-type passive electronic component 100.

  The difference from the conventional chip-type passive electronic component 100 is in the shape of the electrode 11. The electrode 11 according to the present embodiment includes a prismatic joining portion 11b and a substantially hemispherical electrode body 11a that is substantially continuously connected to the prismatic joining portion 11b. By forming the electrode 11 in such a shape, discontinuous points such as the corner 103 of the conventional electrode 101 are eliminated.

  Furthermore, by making the outer diameter of the prismatic joint 11b and the outer diameter of the passive element body 12 substantially the same, the passive element body 102, the electrode 101, and the conventional chip-type passive electronic component 100 are provided. The discontinuous point 104 at the boundary portion is excluded.

  The shape of the chip-type passive electronic component 10 according to this embodiment is not limited to the shape illustrated in FIGS. 1C and 1D as it is. For example, the corner portion 103 of the conventional chip-type passive electronic component 100 may be chamfered in a curved shape. Even in this form, the discontinuity of the corner 103 is eliminated by the curved chamfering, and stress concentration can be avoided.

  Moreover, it is good also as a shape which reduces an outer periphery discontinuous point further with respect to the shape illustrated to FIG.1 (c) and (d). For example, the continuity of the boundary portion between the joint portion 11b and the hemispherical electrode body 11a is improved by making the outer peripheral shape of the joint portion 11b into a cylindrical shape instead of a prismatic shape.

  Further, the continuity of the boundary portion between the cylindrical joint portion 11b and the passive element body 12 is further improved by changing the shape of the passive element body 12 from, for example, a conventional rectangular shape to a cylindrical shape. .

  2C and 2D are views showing an example of the appearance of the electronic component 20 according to the second embodiment, where FIG. 2C is a plan view and FIG. 2D is a side view. Is shown. The electronic component 20 according to the second embodiment is, for example, a semiconductor IC package component 20 such as a CPU, and includes a package main body 21 and a connection portion 22. The semiconductor IC package component 20 is, for example, a BGA (Ball Grid Array) type package, and the connection portion 22 has a large number of solder balls arranged in a lattice array.

  2A and 2B are views showing an example of the appearance of a conventional semiconductor IC package component 200, in which FIG. 2A is a plan view and FIG. 2B is a side view. Is shown.

  The package body 201 of the conventional semiconductor IC package component 200 has a flat rectangular shape, and the corners 203 at the four corners form right-angled discontinuities.

  For this reason, when the conventional semiconductor IC package component 200 is embedded in the resin layer of the component-embedded printed circuit board or when the semiconductor IC package component 200 is resin-sealed from above, the above-described chip-type passive electronic component is used. Similar to 100, stress concentration occurs at the discontinuous points (corner portions 203) on the outer periphery due to the difference in thermal expansion coefficient between the package body 201 and the resin layer. As a result, the resin layer is broken in the vicinity of the corner portion 203, and peeling between the semiconductor IC package component 200 and the resin layer is likely to occur.

  Therefore, in the electronic component 20 (semiconductor IC package component 20) according to the present embodiment, the stress concentration is reduced by forming the four corners of the package body 21 into a curved shape.

  Specifically, as illustrated in FIG. 2C, horizontal curved surface portions 21a are provided at the corners in the horizontal direction of the package body 21, and the vertical direction of the package body 21 is illustrated as illustrated in FIG. The vertical curved surface portion 21b is also provided at the corner portion of the direction.

  As a result, the stress concentration at the corners of the package body 21 is reduced, and the breakage of the resin layer and the separation between the package body 21 and the resin layer due to the damage can be prevented.

(2) Printed Circuit Board FIG. 3 is a cross-sectional view schematically showing the structure of the printed circuit board 30 (component built-in printed circuit board 30) according to the first embodiment.

  The component-embedded printed circuit board 30 includes a first substrate 33 disposed below in FIG. 3, a second substrate 31 disposed above in FIG. 3, and a first substrate 33 and a second substrate. A resin layer 32 filled between the electronic component 10 and the electronic component 10 is provided. The electronic component 10 (chip-type passive electronic component 10) incorporated in the component-embedded printed circuit board 30 is mounted between the first substrate 33 and the second substrate 31 so as to be embedded in the resin layer 32. The

  FIG. 3 is a diagram in which only one chip-type passive electronic component 10 is incorporated in order to schematically explain the structure, but actually a plurality of electronic components are incorporated. Also, on the outer surfaces of the first substrate 33 and the second substrate 31, various electronic components, for example, surface mount components, are mounted in the same manner as a normal substrate. In FIG. The illustration is omitted.

  The built-in electronic component 10 is the chip-type passive electronic component 10 shown in FIGS. 1C and 1D, and has a shape in which the outer peripheral shape is formed in a curved shape and the discontinuous points on the outer periphery are eliminated as much as possible. It is an electronic component.

  When various electronic components mounted on the component-embedded printed circuit board 30 are energized, the temperature of the component-embedded printed circuit board 30 rises, and the built-in chip passive electronic component 10 and the resin layer 32 are overheated. . At this time, since the thermal expansion coefficients of the chip-type passive electronic component 10 and the resin layer 32 are usually different, thermal stress (thermal strain) is generated in the chip-type passive electronic component 10 and the resin layer 32.

  At this time, in the conventional chip-type passive electronic component 100, since there are discontinuous points in the outer periphery shape at the four corners, stress concentration occurs at these discontinuous points, and the resin layer 32 is broken near the discontinuous points. Or peeling may occur.

  On the other hand, in the component built-in type printed circuit board 30 according to the present embodiment, since the outer peripheral shape of the built-in component is formed in a curved surface shape, the stress is dispersed and the stress concentration is unlikely to occur. For this reason, it is possible to prevent the resin layer 32 from being broken or peeled in the vicinity of the outer periphery of the chip-type passive electronic component 10.

  FIG. 4 is a cross-sectional view schematically showing the structure of the printed circuit board 40 according to the second embodiment. In the printed circuit board 40 according to the second embodiment, after mounting the electronic component 10 (chip-type passive electronic component 10) on a normal surface-mount substrate 42, the chip-type passive electronic component 10 is sealed with the resin layer 41. belongs to.

  Also in this case, in the conventional chip-type passive electronic component 10 having outer peripheral discontinuities at the four corners or the like, there is a possibility that the resin layer 41 is broken or peeled in the vicinity of the discontinuous points.

  In contrast, in the printed circuit board 40 according to the second embodiment, the stress concentration is reduced by forming the outer peripheral shape of the chip-type passive electronic component 10 to be mounted into a curved surface, and the chip-type passive electronic component 10 Breakage and peeling of the resin layer 41 in the vicinity of the outer periphery can be prevented.

  FIG. 5 is a cross-sectional view schematically showing a structure in which the semiconductor IC package component 20 is mounted on the printed circuit board 40a according to the second embodiment.

  As shown in FIG. 2, the semiconductor IC package component 20 is formed so that the four corners 21a in the horizontal direction and the four corners 21b in the vertical direction are curved. Therefore, unlike the conventional semiconductor IC package component 200, stress concentration does not occur at the four corners, and the resin layer 41 can be prevented from being broken or peeled off.

(3) Electronic Device An electronic device (not shown) according to the present embodiment is an electronic device that houses at least the component-embedded printed circuit board 30 and the printed circuit board 40 described above, and restricts specific types and structures thereof. It is not a thing. For example, an information processing apparatus such as a personal computer that houses the component-embedded printed circuit board 30 or the printed circuit board 40, or an AV apparatus such as a DVD recording / reproducing apparatus.

  In the component-embedded printed circuit board 30 and the printed circuit board 40 accommodated in these electronic devices, the outer peripheral shape of the chip-type passive electronic component 10 and the semiconductor IC package component 20 is formed in a curved shape, and the resin layer covering them is destroyed. Therefore, high reliability can be maintained as a whole electronic device.

  As described above, according to the electronic component, the printed circuit board, and the electronic device that accommodates the printed circuit board according to the present embodiment, the resin layer is formed by relaxing the stress concentration generated at the corner of the electronic component covered with the resin layer. Can be prevented from being peeled off, and high reliability can be maintained.

  Note that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Moreover, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above embodiments. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, the constituent elements over different embodiments may be appropriately combined.

(C) And (d) is a figure which shows the example of an external appearance of 1st Embodiment (chip-type passive electronic component) of the electronic component which concerns on this invention, (a) And (b) is a conventional electronic The figure which shows the example of external appearance of components (chip-type passive electronic component). (C) And (d) is a figure which shows the external appearance example of 2nd Embodiment (semiconductor IC package component) of the electronic component based on this invention, (a) And (b) is a conventional electronic component The figure which shows the example of an external appearance of (semiconductor IC package component). 1 is a cross-sectional view schematically showing the structure of a printed circuit board according to a first embodiment of the present invention (component-embedded printed circuit board). The 1st sectional view showing typically the structure of a 2nd embodiment of the printed circuit board concerning the present invention. The 2nd sectional view showing typically the structure of the 2nd embodiment of the printed circuit board concerning the present invention.

Explanation of symbols

10 Electronic components (chip-type passive electronic components)
DESCRIPTION OF SYMBOLS 11 Electrode 11a Electrode main body 11b Joint part 12 Passive element main body 20 Electronic component (semiconductor IC package component)
21 Package body 21a Horizontal curved surface portion 21b Vertical curved surface portion 22 Connection portion 30 Printed circuit board (component built-in printed circuit board)
31 Second substrate 32 Resin layer 33 First substrate 40, 40a Printed circuit board 41 Resin layer 42 Surface mount substrate

Claims (12)

A first substrate;
A second substrate;
A resin layer filling an outer periphery of an electronic component mounted between the first substrate and the second substrate;
With
The electronic component is a printed circuit board with a built-in component, wherein an outer peripheral shape thereof is formed in a curved shape. The electronic component is a chip-type passive electronic component having two electrodes at both ends,
The component built-in printed circuit board according to claim 1, wherein the electrode has a substantially hemispherical shape. The electronic component is a semiconductor package component having a substantially square shape,
The component built-in printed circuit board according to claim 1, wherein the shape of the four corners of the semiconductor package component is formed in a curved shape with respect to a horizontal direction and a vertical direction. In an electronic device equipped with a component-embedded printed circuit board,
The component-embedded printed circuit board is
A first substrate;
A second substrate;
A resin layer filling an outer periphery of an electronic component mounted between the first substrate and the second substrate;
With
The electronic component is formed so that an outer peripheral shape thereof is a curved surface,
Electronics. The electronic component is a chip-type passive electronic component having two electrodes at both ends,
The electronic apparatus according to claim 4, wherein the electrode shape is substantially hemispherical. The electronic component is a semiconductor package component having a substantially square shape,
The electronic device according to claim 4, wherein the shape of the four corners of the semiconductor package component is a curved surface with respect to the horizontal direction and the vertical direction. A substrate,
A resin layer for sealing the outer periphery of the electronic component mounted on the substrate;
With
The printed circuit board, wherein the electronic component is formed so that an outer peripheral shape thereof is a curved surface. The electronic component is a chip-type passive electronic component having two electrodes at both ends,
The printed circuit board according to claim 7, wherein the electrode shape is substantially hemispherical. The electronic component is a semiconductor package component having a substantially square shape,
The printed circuit board according to claim 7, wherein the shape of the four corners of the semiconductor package component is a curved surface with respect to the horizontal direction and the vertical direction. In an electronic component incorporated in a component-embedded printed circuit board comprising a first substrate, a second substrate, and a resin layer filling between the first substrate and the second substrate,
The electronic component is formed so that an outer peripheral shape thereof is a curved surface,
Electronic components. The electronic component is a chip-type passive electronic component having two electrodes at both ends,
The electronic component according to claim 10, wherein the electrode shape is substantially hemispherical. The electronic component is a semiconductor package component having a substantially square shape,
11. The electronic component according to claim 10, wherein the shape of the four corners of the semiconductor package component is listed in a curved shape with respect to the horizontal direction and the vertical direction.

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