Mounted components

Abstract

It continues to perform the desired function in environments with temperature fluctuations. [Solution] The mounted component 1 is attached to the substrate electrode 23 provided on the substrate 2 by a solder joint 4. The mounted component 1 comprises a component body 11 and a component electrode 12 exposed from the component body 11. The component electrode 12 includes a back electrode bonding surface 122a that faces the substrate electrode 23 and is in contact with the back solder layer 431, an end electrode bonding surface 121a that extends in a direction upright from the substrate electrode 23 and is in contact with the end solder fillet 41, and an end chamfered electrode bonding surface 125a that connects the back electrode bonding surface 122a to the end electrode bonding surface 121a. The distance of the end chamfered electrode bonding surface 125a from the virtual surface 122K including the back electrode bonding surface 122a gradually increases.

Description

Technical Field

[0001] The present invention relates to mounting components.

Background Art

[0002] A substrate for electronic devices includes a substrate body formed of a resin material such as glass epoxy resin or a metal material, and a copper wiring layer formed on the substrate body via an insulating layer. In recent years, a manufacturing process of mounting electronic components to this wiring by soldering or the like has been widely adopted. In particular, a method called surface mounting has been widely adopted. Surface mounting directly solders component-side electrodes arranged on the lower surface and side surfaces of an electronic component to substrate-side electrodes exposed on the substrate surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Patent Document 9

Patent Document 10

Summary of the Invention

[0004] Substrates, functional elements, and electronic components each have their own unique coefficients of thermal expansion. Furthermore, the wiring and solder joints that electrically connect the functional elements and electronic components also have their own unique coefficients of thermal expansion. When a structure in which components with different coefficients of thermal expansion are fixed together is exposed to an environment with temperature changes, it suffers from thermal shock and thermal fatigue due to the difference in coefficients of thermal expansion. Patent documents 1 to 10 disclose mounting techniques to address such problems.

[0005] The effects of thermal shock and thermal fatigue are particularly noticeable in solder joints. Solder joints affected by thermal shock and thermal fatigue are prone to electrical connection failures, which can prevent the mounted circuit board from continuously performing the desired functions.

[0006] The present invention provides a mounting component that can continue to perform its desired function in environments with temperature changes. [Means for solving the problem]

[0007] One embodiment of the present invention is a mounting component that is attached to a substrate electrode provided on a substrate by solder, comprising a component body and a component electrode including a portion exposed from the component body, wherein the portion of the component electrode exposed from the component body includes a back electrode bonding surface facing the substrate electrode and in contact with solder, a vertical electrode bonding surface extending in a direction upright from the substrate electrode and in contact with solder, and a chamfered electrode bonding surface connecting the back electrode bonding surface to the vertical electrode bonding surface, the chamfered electrode bonding surface includes a portion whose distance from a virtual plane including the back electrode bonding surface gradually increases.

[0008] This mounted component has a chamfered electrode bonding surface that connects the back electrode bonding surface to the vertical electrode bonding surface. The chamfered electrode bonding surface includes a portion where the distance from the virtual plane containing the back electrode bonding surface gradually increases. This allows for a gradual change in the cross-sectional area from the solder formed between the back electrode bonding surface and the substrate electrode to the solder formed between the vertical electrode bonding surface and the substrate electrode. As a result, the degree of stress concentration caused by discontinuous changes in cross-sectional area is mitigated, making it possible to reduce the magnitude of internal stress generated in the solder in environments with temperature changes. Therefore, the connection between the mounted component and the substrate can be maintained, and the desired function can be continuously performed.

[0009] In the above-described mounting component, the chamfered electrode bonding surface may be curved. This configuration also helps to mitigate the degree of stress concentration that occurs in the solder.

[0010] In the above-described mounting component, the chamfered electrode bonding surface may be flat. This configuration also helps to mitigate the degree of stress concentration that occurs in the solder.

[0011] In the above-described mounting component, the chamfered electrode bonding surface is a curved surface, the component body includes a back surface facing the substrate, the component electrode includes a back electrode bonding surface and a back electrode portion bonded to the back surface of the body, and the radius of curvature of the chamfered electrode bonding surface may be greater than the thickness of the back electrode portion. With this configuration, the magnitude of internal stress generated in the solder can be reduced for mounting components that employ a structure in which electrodes are provided on the surface of the component body.

[0012] In the above-described mounting component, the component body includes a back surface facing the substrate, a vertical surface extending upward from the substrate electrodes, and a chamfered surface connecting the back surface to the vertical surface. The chamfered surface includes a portion where the distance from a virtual plane including the back surface gradually increases, and the chamfered electrode bonding surface may be provided on the chamfered surface. This configuration also helps to mitigate the degree of stress concentration in the solder. As a result, for mounting components employing a structure in which electrodes are provided on the component body, the magnitude of internal stress in the solder can be reduced.

[0013] In the above-described mounting component, the component body includes a back surface facing the substrate, a vertical surface extending upward from the substrate electrodes, and a chamfered surface connecting the back surface to the vertical surface. The chamfered surface includes a portion where the distance from a virtual surface including the back surface gradually increases. The component electrodes include portions embedded in recessed areas from the back surface and the vertical surface. The radius of curvature of the curved chamfered surface may be the same as the radius of curvature of the curved chamfered electrode bonding surface. This configuration makes it possible to reduce the amount of internal stress generated in the solder for mounting components that employ a structure in which electrodes are embedded in the component body.

[0014] In the above-described mounting component, the component body includes a back surface facing the substrate, a vertical surface extending upward from the substrate electrodes, and a chamfered surface connecting the back surface to the vertical surface. The chamfered surface includes a portion where the distance from a virtual surface including the back surface gradually increases. The component electrodes include portions embedded in recessed areas from the back surface and the vertical surface. The chamfered surface may be flush with the chamfered electrode bonding surface. This configuration also reduces the magnitude of internal stress generated in the solder for mounting components that employ a structure in which electrodes are embedded in the component body. [Effects of the Invention]

[0015] According to the present invention, a mounting component is provided that can continue to perform the desired function in an environment with temperature changes. [Brief explanation of the drawing]

[0016] [Figure 1] Figure 1 is a perspective view of a mounting component according to the first embodiment. [Figure 2] Figure 2 is a perspective view of a mounting component according to the second embodiment. [Figure 3] Figure 3 is a front view of a cross-section of a mounting component according to the first modification. [Figure 4] Figure 4 is a side view of a cross-section of a mounting component according to the second modification. [Figure 5] Figure 5(a) is a side view of a cross-section of a mounting component according to the third modification. Figure 5(b) is a side view of a cross-section of a mounting component according to the fourth modification. Figure 5(c) is a side view of a cross-section of a mounting component according to the fifth modification.

Mode for Carrying Out the Invention

[0017] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same reference numerals are assigned to the same elements, and redundant descriptions are omitted.

[0018] <First Embodiment> As shown in FIG. 1, the mounting component 1 is attached to the substrate 2 by a solder joint 4. The portion of the mounting component 1 where the solder joint 4 contacts is subjected to so-called chamfering. As a result, according to the chamfered corner, the internal stress generated in the solder joint 4 is relaxed.

[0019] The substrate 2 constitutes a mounting substrate that forms a desired electronic circuit by connecting a plurality of mounting components 1 to each other. FIG. 1 shows one of the plurality of mounting components 1 arranged on the substrate 2. The substrate 2 is provided with a plurality of other types of mounting components 1 not shown in FIG. 1. In the following description, the mounting structure 10 is defined as fixing one mounting component 1 to the substrate 2.

[0020] The substrate 2 is what is commonly referred to as a glass epoxy substrate, metal-based substrate, or metal-core substrate. The substrate 2 comprises a substrate body 21, a resist layer 22 (insulating layer), and substrate electrodes 23. The substrate body 21 is, for example, a plate-shaped member formed from glass epoxy.

[0021] The substrate body 21 is provided with a resist layer 22 and two substrate electrodes 23. The resist layer 22 is formed of a non-conductive material. The substrate electrodes 23 are formed of a conductive material. For example, the substrate electrodes 23 may be made of copper. The substrate electrodes 23 have a main substrate electrode surface 23a. A mounted component 1 is fixed to the main substrate electrode surface 23a via a solder joint 4. The mounted component 1 is not in direct contact with the main substrate electrode surface 23a.

[0022] Mounted component 1 is an electronic component attached to the substrate 2 by so-called surface mounting. Examples of mounted component 1 include surface mount resistors (chip resistors), chip capacitors, and semiconductor packages. The mounting structure 10 is beneficial for mounting components with high strength and rigidity or large size. Mounted component 1 has a component body 11 and two component electrodes 12. The component body 11 is the part that performs electrical functions such as resistance or capacitance. The shape of the component body 11 may be a rectangular parallelepiped, for example. The component body 11 has a main body surface 11a, a back body surface 11b, two side body surfaces 11s (see Figure 3), and two end body surfaces 11e (vertical body surfaces).

[0023] As shown in the enlarged section Z1 of Figure 1, a curved chamfered surface 11c is formed between the back surface 11b and the lower end of the end surface 11e of the main body. This chamfered surface 11c is intentionally created during the manufacturing of the main body 11 by machining or bending. Therefore, a portion corresponding to the chamfered surface 11c is not necessarily formed between the main surface 11a and the side surface 11s of the main body. The portion where the upper ends of the main surface 11a and the end surface 11e are connected may also have a slight curvature, but the curvature of the portion where the back surface 11b and the end surface 11e are connected (the chamfered surface 11c) is clearly larger. This chamfered surface 11c may be defined as a separate portion from the back surface 11b and the end surface 11e of the main body, or it may be defined as a part of the back surface 11b. Alternatively, the chamfered surface 11c may be defined as a part of the end surface 11e of the main body.

[0024] The component electrode 12 includes a portion that covers the main body end face 11e (end face electrode portion 121), a portion that covers a part of the main body back surface 11b (back surface electrode portion 122), a portion that covers a part of the main body main surface 11a (main surface electrode portion 123), a portion that covers a part of the main body side surface 11s (side surface electrode portion 124), and a portion that covers the main body end chamfered surface 11c (chamfered electrode portion 125). Furthermore, these five portions are integrally formed. The component electrode 12 protrudes from the surface of the component body 11. For example, the electrode thickness 122t can be defined as the length from the main body back surface 11b to the back surface electrode bonding surface 122a.

[0025] Since the main body end face 11e is flat, the end face electrode portion 121 is also flat. Since the main body back surface 11b is also flat, the back surface electrode portion 122 is also flat. On the other hand, since the main body end chamfered surface 11c is curved, the chamfered electrode portion 125 is curved. The shape of this chamfered electrode portion 125 can also be defined by the radius of curvature 125r. For example, the radius of curvature 125r of the chamfered electrode portion 125 is greater than the electrode thickness 122t of the back surface electrode portion 122. Such a chamfered electrode portion 125 with a radius of curvature 125r can be provided because the main body 11 has a chamfered surface 11c formed on its end. Here, the radius of curvature 125r is assumed to be the average radius of curvature of the chamfered electrode portion 125, but it may also be the minimum radius of curvature of the chamfered electrode portion 125. For example, if a chamfered surface 11c is not provided between the back surface 11b and the end surface 11e of the main body, it is not possible to provide a chamfered electrode portion 125 with a radius of curvature 125r that is larger than the electrode thickness 122t. Therefore, the "chamfered electrode portion 125" in this embodiment can also be said to be a part of the electrode formed on the chamfered surface of the component body 11.

[0026] The solder joint 4 has the function of physically fixing the mounted component 1 to the substrate 2 and the function of electrically connecting it. The specific process for forming the solder joint 4 is not particularly limited. For example, the solder joint 4 may be formed by a reflow soldering process, a flow soldering process, a manual soldering process, or a soldering iron process such as that used by a robot.

[0027] The material used for the solder joint 4 is not particularly limited. For example, examples of solder joints 4 include leaded solders such as eutectic solder and high-temperature solder, and lead-free solders such as Sn-Ag-Cu solder and Sn-Bi solder. The form of the solder used for the solder joint 4 is also not particularly limited. For example, various forms such as paste solder, solder wire, die-cut plate solder, and solder rod can be applied to the solder joint 4.

[0028] The solder joint 4 includes an end face solder fillet 41, a side face solder fillet 42, and a solder layer 43. These together form the solder joint 4. The end face solder fillet 41 is provided between the main surface 23a of the substrate electrode and the end face electrode bonding surface 121a (vertical electrode bonding surface). The side face solder fillet 42 is provided between the main surface 23a of the substrate electrode and the side face electrode bonding surface 124a (see Figure 3). The solder layer 43 is provided between the main surface 23a of the substrate electrode and the back surface electrode bonding surface 122a. The end face solder fillet 41, the side face solder fillet 42, and the solder layer 43 are formed as a single unit.

[0029] Looking at the solder layer 43 in more detail, it includes a back solder layer portion 431 that is in contact with the back electrode bonding surface 122a, and an end chamfered solder layer portion 432 that is in contact with the end chamfered electrode bonding surface 125a of the chamfered electrode portion 125. The back solder layer portion 431 is the portion formed between the back electrode bonding surface 122a and the substrate electrode main surface 23a. The back electrode bonding surface 122a is a plane, and the substrate electrode main surface 23a is also a plane. If the mounted component 1 is fixed to the substrate 2 without tilting, then the back electrode bonding surface 122a is parallel to the substrate electrode main surface 23a. As a result, the height from the substrate electrode main surface 23a to the back electrode bonding surface 122a is constant. Therefore, the thickness 431t of the back solder layer portion 431 formed between the substrate electrode main surface 23a and the back electrode bonding surface 122a can also be considered to be a constant value.

[0030] In contrast, the chamfered end electrode bonding surface 125a is a curved surface. Therefore, the height from the substrate electrode main surface 23a to the chamfered end electrode bonding surface 125a is not constant. Now, we define a virtual surface 122K that includes the back electrode bonding surface 122a of the back electrode portion 122. In this embodiment, the back electrode portion 122 is a flat surface, and the virtual surface 122K is a plane that extends the back electrode portion 122 along the flat surface. Therefore, one end of the chamfered end electrode bonding surface 125a is connected to the back electrode bonding surface 122a on the virtual surface 122K. As we move towards the other end of the chamfered end electrode bonding surface 125a, the distance from the virtual surface 122K gradually increases. The other end of the chamfered end electrode bonding surface 125a is connected to the end electrode bonding surface 121a. Furthermore, the same applies when using the substrate electrode main surface 23a as a reference; as you approach the end electrode portion 121, the height from the substrate electrode main surface 23a to the end chamfered electrode bonding surface 125a gradually increases. As a result, the thickness of the end chamfered solder layer portion 432 formed between the substrate electrode main surface 23a and the end chamfered electrode bonding surface 125a also increases as you approach the end electrode portion 121.

[0031] The formation of this chamfered end solder layer 432 between the back surface solder layer 431 and the end face solder fillet 41 causes the cross-sectional area of ​​the solder joint 4 to increase continuously. In other words, the solder joint 4 does not have any parts where the cross-sectional area changes discontinuously. By providing the chamfered end solder layer 432, the change in cross-sectional area becomes gradual, thereby reducing the degree of so-called stress concentration. As a result, it becomes possible to reduce the maximum value of internal stress generated in the solder joint 4.

[0032] <Effects and Effects> The mounted component 1 is attached to the substrate electrode 23 provided on the substrate 2 by a solder joint 4. The mounted component 1 comprises a component body 11 and component electrodes 12 exposed from the component body 11. The component electrode 12 includes a back electrode bonding surface 122a facing the substrate electrode 23 and in contact with the back solder layer 431, an end electrode bonding surface 121a extending in a direction upright from the substrate electrode 23 and in contact with the end solder fillet 41, and an end chamfered electrode bonding surface 125a connecting the back electrode bonding surface 122a to the end electrode bonding surface 121a. The distance of the end chamfered electrode bonding surface 125a from the virtual surface 122K including the back electrode bonding surface 122a gradually increases.

[0033] The mounted component 1 has an end-chamfered electrode joint surface 125a that connects the back electrode joint surface 122a to the end electrode joint surface 121a. The distance of the end-chamfered electrode joint surface 125a from the virtual surface 122K, which includes the back electrode joint surface 122a, gradually increases. This makes it possible to gradually change the cross-sectional area from the back solder layer 431 formed between the back electrode joint surface 122a and the substrate electrode main surface 23a to the end solder fillet 41 formed between the end electrode joint surface 121a and the substrate electrode main surface 23a. As a result, the degree of stress concentration caused by discontinuous changes in cross-sectional area is mitigated, making it possible to reduce the magnitude of internal stress generated in the solder joint 4 in environments with temperature changes. Therefore, the joint between the mounted component 1 and the substrate 2 can be maintained, and the desired function can be continuously performed.

[0034] The chamfered end electrode bonding surface 125a is a curved surface. The component body 11 includes a body back surface 11b facing the substrate 2. The component electrode 12 includes a back electrode bonding surface 122a and a back electrode portion 122 provided on the body back surface 11b. The radius of curvature 125r of the chamfered end electrode bonding surface 125a is greater than the electrode thickness 122t of the back electrode portion 122. With this configuration, the amount of internal stress generated in the solder joint 4 can be reduced for a mounted component 1 that employs a structure in which the component electrode 12 is provided on the component body 11.

[0035] The component body 11 includes a back surface 11b facing the substrate 2, a body end surface 11e extending upward from the substrate electrode 23, and a body end chamfer surface 11c connecting the back surface 11b to the body end surface 11e. The distance of the body end chamfer surface 11c from the virtual surface 11K including the back surface 11b gradually increases. The end chamfer electrode bonding surface 125a is provided on the body end chamfer surface 11c. This configuration also makes it possible to mitigate the degree of stress concentration that occurs in the solder joint 4. As a result, for mounted components 1 that employ a structure in which component electrodes 12 are provided on the component body 11, the magnitude of internal stress that occurs in the solder joint 4 can be reduced.

[0036] <Second Embodiment> Figure 2 is a perspective view showing a mounting structure 50 composed of mounting components 5 of the second embodiment. The mounting components 5 of the second embodiment employ a package known as a QFN (Quad Flat Non-leaded package). The mounting components 5 of the second embodiment comprises one central electrode body 53 and a plurality of peripheral electrode bodies 54, and these electrode bodies are connected to the substrate electrode 63 by solder joints 7.

[0037] The substrate 6 comprises a substrate body 61 and a plurality of substrate electrodes 63. The substrate 6 differs from the substrate 2 of the first embodiment only in that the arrangement of the substrate electrodes 63 exposed from the main surface 61a of the substrate body corresponds to the central electrode body 53 and the plurality of surrounding electrode bodies 54 of the mounted component 5. Therefore, a detailed description of the substrate 6 will not be repeated.

[0038] The mounted component 5 comprises a main package 51 (component body), a semiconductor chip 52, a central electrode body 53, and a plurality of peripheral electrode bodies 54 (component electrodes). The semiconductor chip 52 is placed on the central electrode body 53. As a result, electrodes (not shown) provided on the back surface of the semiconductor chip 52 are connected to the substrate electrodes 63 via the central electrode body 53. Electrodes provided on the main surface of the semiconductor chip 52 are connected to the peripheral electrode bodies 54 via bonding wires 56. As a result, electrodes provided on the main surface of the semiconductor chip 52 are connected to the substrate electrodes 23 via the peripheral electrode bodies 54.

[0039] The main package 51 fixes the relative positions of the semiconductor chip 52, the central electrode 53, and the surrounding electrode 54. The semiconductor chip 52, the central electrode 53, and the surrounding electrode 54 are placed in predetermined positions using a jig, and the resin material that will become the main package 51 is filled into the jig so as to embed these components. As a result, a main package 51 with the semiconductor chip 52, the central electrode 53, and the surrounding electrode 54 embedded in it can be obtained.

[0040] Referring to the enlarged section Z2 in Figure 2, the peripheral electrode body 54 includes an electrode exposed end face 54e and an electrode exposed back surface 54b. The electrode exposed end face 54e and the electrode exposed back surface 54b are exposed from the main package 51. In other words, "exposed" indicates whether or not it is exposed from the main package 51, and even if it is covered by the solder joint 7, as in the case of the electrode exposed back surface 54b, it is considered to be exposed from the main package 51. The electrode exposed end face 54e and the electrode exposed back surface 54b are connected to the main surface 63a of the substrate electrode 63 via the solder joint 7. The electrode exposed end face 54e may, for example, be flush (on the same surface) with the package end face 51e (main body vertical surface). Similarly, the electrode exposed back surface 54b may, for example, be flush with the package back surface 51b (main body back surface).

[0041] Furthermore, the peripheral electrode body 54 includes an electrode rear end face 54d and an electrode main surface 54a. The electrode rear end face 54d and the electrode main surface 54a are not exposed from the main package 51. The electrode rear end face 54d and the electrode main surface 54a are in contact with the main package 51. The main package 51 has a package recess 51P (recessed area) formed therein for embedding the peripheral electrode body 54. The package recess 51P is an area surrounded by a recess upper surface 51Pa and a recess rear surface 51Pb. The electrode rear end face 54d is in contact with the recess rear surface 51Pb. The electrode main surface 54a is in contact with the recess upper surface 51Pa.

[0042] In the first embodiment, the mounted component 1 had a chamfered electrode portion 125 between the end face electrode portion 121 and the back face electrode portion 122. The mounted component 5 of the second embodiment also has a similar chamfered portion. The periphery electrode body 54 has a chamfered electrode bonding surface 54c formed between the electrode exposed end face 54e and the electrode exposed back face 54b. In the first embodiment, the component electrode 12 was provided so as to overlap the surface of the component body 11. Therefore, the component electrode 12 could be defined by a predetermined thickness. In contrast, in the second embodiment, the periphery electrode body 54 is embedded in the main body package 51. Therefore, in the second embodiment, the shape of the chamfered electrode bonding surface 54c is not defined using the thickness of the electrode body.

[0043] The chamfered electrode bonding surface 54c can be formed, for example, by chamfering the corner where the package end face 51e and the package back surface 51b are at a right angle. In the enlarged section Z2 of Figure 2, the chamfered electrode bonding surface 54c is formed by so-called R-chamfering. In this case, a package chamfered surface 51c (main body chamfered surface, see enlarged section Z3 of Figure 2) is also formed on the main package 51. As a result, the radius of curvature of the chamfered electrode bonding surface 54c formed on the surrounding electrode body 54 is the same as the radius of curvature of the package chamfered surface 51c of the main package 51. In other words, the mounted component 5 of the second embodiment comprises a main package 51 including the package chamfered surface 51c and a surrounding electrode body 54 including the chamfered electrode bonding surface 54c. Furthermore, the package chamfered surface 51c is not covered by the chamfered electrode bonding surface 54c as in the first embodiment, but is exposed to the outside.

[0044] When the mounting component 5 of the second embodiment is attached to the substrate 6, a solder joint 7 similar to that of the first embodiment is formed. The solder joint 7 includes an end face solder fillet 71 and a solder layer 73. Furthermore, the solder layer 73 includes a back surface solder layer portion 731 that contacts the exposed back surface 54b of the electrode and an end chamfered solder layer portion 732 that contacts the chamfered electrode bonding surface 54c.

[0045] <Effects and Effects> In the mounting component 5 of the second embodiment, the main package 51 includes a package back surface 51b facing the substrate 6, a package end surface 51e extending in a direction upright from the substrate electrodes 63, and a package chamfer surface 51c connecting the package back surface 51b to the package end surface 51e. The distance of the package chamfer surface 51c from the virtual surface 51K including the package back surface 51b gradually increases. The peripheral electrode body 54 is embedded in a package recess 51P recessed from the package back surface 51b and the package end surface 51e. The radius of curvature of the curved package chamfer surface 51c is the same as the radius of curvature of the curved electrode chamfer surface. With this configuration, for mounting component 5 that employs a structure in which the peripheral electrode body 54 is embedded in the main package 51, the magnitude of internal stress generated in the solder joint 7 can be reduced.

[0046] <Variation> The mounting components of the present invention are not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention.

[0047] <First variation> The mounted component 1 of the first embodiment had a chamfered electrode portion 125 provided between the end electrode portion 121 and the back electrode portion 122. Figure 3 shows a mounted component 1A of the first modified example that constitutes the mounted structure 10A. Such a chamfer may be formed between the back electrode portion 122 and the side electrode portion 124. As shown in Figure 3, the component body 11A has a body side chamfered surface 11d formed between the body side surface 11s and the body back surface 11b. Furthermore, the component electrode 12A includes a side chamfered electrode joint surface 126a, which is a curved surface similar to the end chamfered electrode joint surface 125a. In that case, the solder layer 43A of the solder joint 4A further includes a side chamfered solder layer portion 433 in addition to the back solder layer portion 431 and the end chamfered solder layer portion 432. The side chamfered solder layer portion 433 is provided between the body side chamfered surface 11d and the substrate electrode main surface 23a. The formation of this chamfered side solder layer 433 between the back solder layer 431 and the side solder fillet 42 causes the cross-sectional area of ​​the solder joint 4A to continuously increase. Consequently, the change in cross-sectional area becomes gradual, reducing the degree of stress concentration. As a result, it becomes possible to reduce the maximum value of internal stress generated in the solder joint 4A.

[0048] <Second variation> The mounting component 5 of the second embodiment had a central electrode body 53 and a peripheral electrode body 54 embedded in the main package 51. Figure 4 shows a part of the mounting structure 50B composed of the mounting component 5B of the second modified example. The mounting component 5B of the second modified example may have a package electrode 55B that contacts the package end face 51e and the package back surface 51b of the main package 51B. This package electrode 55B has the same configuration as the component electrode 12 of the first embodiment. That is, the package electrode 55B has an end face electrode portion 511 that contacts the package end face 51e, a back surface electrode portion 512 that contacts the package back surface 51b, and a chamfered electrode portion 515 that contacts the package chamfered surface 51c. Even with such a package electrode 55B, it is possible to reduce the maximum value of internal stress generated in the solder joint 7.

[0049] <Third variation> In the mounting component 1 of the first embodiment, the chamfered electrode portion 125, which is a connecting portion that connects the end face electrode portion 121 to the back face electrode portion 122, included a curved end chamfered electrode joint surface 125a. As shown in the mounting component 1C of the third modified example shown in Figure 5(a), the side chamfered electrode joint surface 125d included in the chamfered electrode portion 125C may be flat. Such a side chamfered electrode joint surface 125d is called a C-chamfer. Even with such a side chamfered electrode joint surface 125d, the thickness of the end chamfered solder layer portion 432 that constitutes the solder layer 43 increases as it approaches the end face electrode portion 121. Therefore, it becomes possible to reduce the maximum value of internal stress generated in the solder joint 4. In this embodiment, the C-chamfered portion is smoother than the corner between the upper surface facing the back surface 11b of the component body 11A and the end face 11e of the component body. In other words, the chamfering process is applied to a wider area than the corner between the top surface facing the back surface 11b of the main body and the end surface 11e of the main body.

[0050] <Fourth variation> The planar chamfer configuration shown in the third modified example can also be applied to a mounted component 5D using a QFN package, as shown in Figure 5(b). The mounted component 5D has an embedded electrode body 54D. The electrode body 54D includes an electrode chamfered surface 54g formed by C-chamfering. In this embodiment, the C-chamfered portion is smoother than the corner between the electrode main surface 54a and the electrode exposed end surface 54e. In other words, the C-chamfering is applied over a wider area than the corner between the electrode main surface 54a and the electrode exposed end surface 54e.

[0051] <Fifth variation> Furthermore, the planar chamfer configuration shown in the third modification can also be applied to a mounted component 5E using a QFN package, as shown in Figure 5(c). The mounted component 5E has electrodes 55E provided on the package end face 51e and the package back surface 51b. The main package 51E has a planar package chamfer surface 51g. The electrodes 55E include an end face electrode portion 551 provided on the package end face 51e, a back surface electrode portion 552 provided on the package back surface 51b, and a chamfer electrode portion 553 provided on the package chamfer surface 51g. [Explanation of symbols]

[0052] 1,1A,1C mounted components 11a Main body surface 11b Back of the main unit 11e Body end face (main body elevation) 11s side of the device 11c Chamfered edge of main body 11d Chamfered surface on the side of the main body 11K virtual screen 12,12A component electrodes 121 End electrode section 121a End electrode joint surface 122 Backside electrode section 122a Back electrode bonding surface 122K virtual faces 124 Side electrode part 124a Side electrode joint surface 125 Chamfered electrode section 125a End chamfered electrode bonding surface 125r radius of curvature 126a Side chamfered electrode bonding surface 2 circuit boards 22 Resist Layers 23 Substrate electrodes 23a Main surface of substrate electrode 4.4A solder joint 41 End face solder fillet 42 Side solder fillets 43,43A solder layer 431 Backside solder layer 432 End chamfered solder layer 433 Side chamfered solder layer 5. Mounted Components 5B Mounted Components 5D mounted components 5E Mounting Components 50B Implementation Structure 51, 51E Main package (main component) 51b Back of the package (back of the product) 51c Package chamfered surface (body chamfered surface) 51e Package end face (body vertical surface) 51g package chamfered edge 51K virtual face 51P Package recess (indented area) 52 Semiconductor Chips 53 Central electrode body 54. Surrounding electrode body (component electrode) 54a Electrode main surface 54b Electrode exposed back side 54c Chamfered electrode bonding surface 54d Electrode back end surface 54D electrode body 54e Electrode exposed end face 54g electrode chamfered surface 55B Package Electrode 56 Bonding wires 511,551 End electrode section 512,552 Backside electrode section 515,553 Chamfered electrode section 6 circuit boards 63 Substrate electrodes 63a Main surface of substrate electrode 7 Solder joints 71 End face solder fillet 73 Solder Layers 731 Backside solder layer 732 End chamfered solder layer

Claims

1. A mounting component that is attached to a substrate electrode provided on a substrate by solder, The main part and The component electrode includes a portion that is exposed from the main body of the component, The portion of the component electrode exposed from the component body includes a back electrode bonding surface facing the substrate electrode and in contact with the solder, a vertical electrode bonding surface extending in a direction upright from the substrate electrode and in contact with the solder, and a chamfered electrode bonding surface connecting the back electrode bonding surface to the vertical electrode bonding surface. The chamfered electrode bonding surface includes a portion where the distance from the virtual surface including the back electrode bonding surface gradually increases, in a mounted component.

2. The mounting component according to claim 1, wherein the chamfered electrode bonding surface is a curved surface.

3. The mounting component according to claim 1, wherein the chamfered electrode bonding surface is flat.

4. The aforementioned chamfered electrode bonding surface is a curved surface, The component body includes the back surface of the body facing the substrate, The component electrode includes the back electrode bonding surface and a back electrode portion that is bonded to the back surface of the main body, The mounting component according to claim 1, wherein the radius of curvature of the chamfered electrode bonding surface is greater than the thickness of the back electrode portion.

5. The component body includes a back surface facing the substrate, a vertical surface extending upward from the substrate electrodes, and a chamfered surface connecting the back surface to the vertical surface. The chamfered surface of the main body includes a portion where the distance from the virtual surface including the back surface of the main body gradually increases. The mounting component according to claim 1, wherein the chamfered electrode bonding surface is provided on the chamfered surface of the main body.

6. The component body includes a back surface facing the substrate, a vertical surface extending upward from the substrate electrodes, and a chamfered surface connecting the back surface to the vertical surface. The chamfered surface of the main body includes a portion where the distance from the virtual surface including the back surface of the main body gradually increases. The aforementioned component electrode includes portions embedded in recessed areas from the back surface and the vertical surface of the main body, The mounting component according to claim 1, wherein the radius of curvature of the curved chamfered surface of the main body is the same as the radius of curvature of the curved chamfered electrode bonding surface.

7. The component body includes a back surface facing the substrate, a vertical surface extending upward from the substrate electrodes, and a chamfered surface connecting the back surface to the vertical surface. The chamfered surface of the main body includes a portion where the distance from the virtual surface including the back surface of the main body gradually increases. The aforementioned component electrode includes portions embedded in recessed areas from the back surface and the vertical surface of the main body, The mounting component according to claim 1, wherein the chamfered surface of the main body is flush with the chamfered electrode bonding surface.

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