Mounting structure of mounted components and method of mounting mounted components.

Abstract

It continues to perform the desired function in environments with temperature fluctuations. [Solution] The mounting structure 10 comprises a substrate 2, a mounting component 3 which includes a component body 31 and a component electrode 32 provided on the surface of the component body 31 and is fixed to the substrate electrode 23 of the substrate 2 by solder, and a spacer portion 311 disposed between the main substrate surface 2a of the substrate 2 and the back surface 31b of the component body 31. The thickness of the spacer portion 311 is greater than the thickness of the component electrode 32.

Description

Technical Field

[0001] The present invention relates to a mounting structure of mounting components and a method of mounting mounting components.

Background Art

[0002] A substrate for electronic equipment 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 on this wiring by soldering or the like has been widely adopted. In particular, a method called surface mounting has been widely adopted. Surface mounting is a method of directly soldering 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

Summary of the Invention

Problems to be Solved by 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 each 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 7 disclose mounting techniques to address such problems.

[0005] Thermal shock and thermal fatigue are particularly likely to manifest in solder joints in the structure of a circuit board. Solder joints affected by thermal shock and thermal fatigue are prone to electrical connection failures, which may prevent the circuit board from continuing to perform the desired functions required of it.

[0006] The present invention provides a mounting structure for a mounted component and a method for mounting a mounted component that can continue to perform the desired function in an environment with temperature changes. [Means for solving the problem]

[0007] A mounting structure for a mounted component, according to one embodiment of the present invention, comprises a substrate, a mounted component including a component body and component electrodes provided on the surface of the component body, which are fixed to the substrate electrodes of the substrate by solder, and a spacer portion disposed between the main surface of the substrate and the back surface of the component body, wherein the thickness of the spacer portion is greater than the thickness of the component electrodes.

[0008] In this mounting structure, a spacer, thicker than the component electrodes, is placed between the main surface of the substrate and the back surface of the mounted component. This creates a gap between the component electrodes and the substrate electrodes, corresponding to the difference in thickness between the component electrodes and the spacer. The solder layer is formed in this gap, preventing the solder layer from becoming too thin. As a result, the degree of stress concentration that may occur in the solder layer in environments with temperature changes is mitigated. Therefore, electrical connection failures are less likely to occur in solder joints affected by thermal shock and thermal fatigue, allowing the mounted substrate to continue to perform the desired functions.

[0009] The above mounting structure may further include a solder layer formed between the back surface of the component electrode and the substrate electrode. This structure allows for the formation of a solder layer with reduced stress concentration.

[0010] In the above mounting structure, the spacer portion includes a plurality of protrusions positioned between the main surface of the substrate and the back surface of the main body, and the area enclosed by the plurality of protrusions in a plan view may include the center of gravity of the mounted component. With this structure, the mounted component can be stabilized when it is placed on the substrate.

[0011] In the above mounting structure, the spacer portion includes a single projection positioned between the main surface of the substrate and the back surface of the main body, and the area occupied by the single projection in a plan view may include the center of gravity of the mounted component. This structure also allows for the stabilization of the mounted component when it is placed on the substrate.

[0012] In the above mounting structure, the spacer portion may be part of the mounted component, or a projection that protrudes from the back surface of the mounted component's body. With this structure, a gap can be formed between the component electrode and the substrate electrode simply by placing the mounted component on the substrate.

[0013] In the above mounting structure, the spacer portion may be a part of the substrate, or a projection that protrudes from the main surface of the substrate. With this structure as well, a gap can be formed between the component electrode and the substrate electrode simply by placing the mounted component on the substrate.

[0014] In the above mounting structure, the substrate may include a substrate body, an insulating layer formed in a first region on the main surface of the substrate body, and a spacer layer which is a spacer portion formed in a second region on the main surface of the substrate body. With this structure as well, a gap can be formed between the component electrodes and the substrate electrodes simply by placing the mounted component on the substrate.

[0015] Another embodiment of the present invention is a mounting structure for a mounted component, comprising a substrate, a mounted component including a component body and component electrodes provided on the surface of the component body, fixed to the substrate electrodes of the substrate by solder, and a solder layer formed between the back surface of the component electrodes and the substrate electrodes, wherein the main surface of the substrate includes a region facing the main surface of the substrate that faces the back surface of the component body, the back surface of the component body includes a region facing the back surface of the component that faces the main surface of the substrate, and the region facing the main surface of the substrate may be parallel to the region facing the back surface of the component. This mounting structure also reduces the degree of stress concentration that may occur in the solder layer, so that the mounted substrate can continue to perform the desired functions required of it.

[0016] A further embodiment of the present invention is a method for mounting a component, comprising the steps of forming a solder preparation structure in which a spacer portion is placed between the main surface of the substrate and the back surface of the component, including the component body and component electrodes provided on the surface of the component body, thereby forming a gap between the substrate electrodes of the substrate and the component electrodes; and providing a solder joint between the substrate electrodes and the component electrodes. According to this mounting method, a solder layer capable of mitigating the degree of stress concentration can be formed. Therefore, electrical connection failures are less likely to occur in solder joints affected by thermal shock and thermal fatigue, and the mounted substrate can continue to perform the desired functions required of it.

[0017] In the above implementation method, the spacer portion is part of the mounted component and is a projection that protrudes from the back surface of the mounted component's body. The process may further include a step of preparing the mounted component including the spacer portion before the step of forming the solder preparation structure. This step allows for the formation of a gap between the component electrode and the substrate electrode simply by placing the mounted component on the substrate.

[0018] In the above implementation method, the spacer portion is a part of the substrate and a projection that protrudes from the main surface of the substrate. The process may further include a step of preparing the substrate including the spacer portion before the step of forming the solder preparation structure. This step also allows for the formation of a gap between the component electrode and the substrate electrode simply by placing the mounted component on the substrate.

[0019] In the above-described mounting method, the spacer portion is a spacer member separate from the substrate and the mounted component. Before the step of forming the solder preparation structure, there may be further steps of placing the spacer member on the main surface of the substrate and, after the step of providing the solder joint, removing the spacer member from between the main surface of the substrate and the component electrode. According to this step, a mounting structure in which no spacer member remains can be obtained.

Effects of the Invention

[0020] According to the present invention, there are provided a mounting structure of a mounted component capable of continuously exhibiting a desired function in an environment accompanied by temperature changes and a method of mounting the mounted component.

Brief Description of the Drawings

[0021] [Figure 1] FIG. 1 is a cross-sectional perspective view showing the mounting structure of the first embodiment. [Figure 2] FIG. 2 is a plan view of the mounting structure shown in FIG. 1. [Figure 3] FIG. 3 is a flowchart showing a mounting method for obtaining the mounting structure shown in FIG. 1. [Figure 4] FIGS. 4(a), 4(b) and 4(c) are cross-sectional views showing each step shown in the flowchart of FIG. 2. [Figure 5] FIG. 5 is a cross-sectional perspective view showing the mounting structure of the second embodiment. [Figure 6] FIG. 6 is a flowchart showing a mounting method for obtaining the mounting structure shown in FIG. 5. [Figure 7] FIGS. 7(a), 7(b) and 7(c) are cross-sectional views showing each step shown in the flowchart of FIG. 6. [Figure 8] FIG. 8 is a cross-sectional perspective view showing the mounting structure of the third embodiment. <OO00111>FIG. 9 is a flowchart showing a mounting method for obtaining the mounting structure shown in FIG. 8. [Figure 10]Figures 10(a), 10(b), and 10(c) are cross-sectional views showing each step in the flowchart of Figure 9. [Figure 11] Figures 11(a) and 11(b) are cross-sectional views showing each step in the flowchart of Figure 9, following Figure 10. [Figure 12] Figure 12(a) is a perspective view showing the main parts of the mounted components in the first modified mounting structure. Figure 12(b) is a plan view of the mounting structure in the first modified mounting structure. [Figure 13] Figure 13 is a perspective view showing the main part of the substrate in the second modified mounting structure. [Modes for carrying out the invention]

[0022] Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the attached drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant explanations are omitted.

[0023] <First Embodiment> As shown in Figure 1, the mounting structure 10 consists of a substrate 2 and mounting components 3. The mounting components 3 are attached to the substrate 2 by solder joints 4. The solder joint 4 of the mounting structure 10 of the first embodiment includes a solder layer 43 sandwiched between the substrate 2 and the mounting components 3. This solder layer 43 can alleviate internal stress generated in the solder joint 4. The mounting structure 10 of the first embodiment will be described in detail below.

[0024] The substrate 2 constitutes a mounting substrate 100 that forms a desired electronic circuit by interconnecting multiple mounted components 3. Figure 1 illustrates one of the multiple mounted components 3 arranged on the substrate 2. The substrate 2 is provided with multiple other types of mounted components 3 that are not shown in Figure 1. In the following description, the mounting structure 10 is defined as a structure in which one mounted component 3 is fixed to the substrate 2.

[0025] The substrate 2 is a so-called glass epoxy substrate, metal-based substrate, or metal-core substrate. The substrate 2 has 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 of glass epoxy. The substrate body 21 includes the main surface 21a of the substrate body.

[0026] The main surface 21a of the substrate body is provided with a resist layer 22 and two substrate electrodes 23. On the main surface 21a of the substrate body, the region where the resist layer 22 is provided and the region where the substrate electrodes 23 are provided do not overlap. The resist layer 22 is formed of a non-conductive material. The resist layer 22 has a resist layer main surface 22a and a resist layer back surface 22b. The resist layer main surface 22a includes a substrate main surface facing region 22a1 that is covered by the mounted component 3. The resist layer main surface 22a also includes a non-facing region 22a2 that is not covered by the mounted component 3. The resist layer back surface 22b is in contact with the main surface 21a of the substrate body. 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 substrate electrode main surface 23a and a substrate electrode back surface 23b. The mounted component 3 is fixed to the main surface 23a of the substrate electrode via a solder joint 4. The mounted component 3 does not directly contact the main surface 23a of the substrate electrode. The back surface 23b of the substrate electrode is in contact with a wiring pattern (not shown) provided on the main surface 21a of the substrate body. The wiring pattern is covered with the resist layer 22 described above.

[0027] The mounted component 3 is an electronic component attached to the substrate 2 by so-called surface mounting. Examples of mounted components 3 include surface mount resistors (chip resistors), chip capacitors, and semiconductor packages. The mounting structure 10 of this embodiment is beneficial for mounting components with high strength and rigidity or large size. The mounted component 3 has a component body 31 and two component electrodes 32. The component body 31 is the part that performs electrical functions such as resistance or capacitance. The shape of the component body 31 may be a rectangular parallelepiped, for example. The component body 31 has a main body surface 31a, a back body surface 31b, two side body surfaces 31s (see Figure 2), and two end body surfaces 31e.

[0028] The back surface 31b of the main body faces the main surface facing region 22a1 of the substrate. In this embodiment, the entire surface of the back surface 31b of the main body faces the main surface facing region 22a1 of the substrate. Therefore, the back surface 31b of the main body can also be said to be the component back surface facing region. The back surface 31b of the main body is provided with a spacer portion 311 that protrudes toward the substrate 2. The spacer portion 311 may be formed integrally with the component body 31. The spacer portion 311 may be fixed to the component body 31 by adhesive. In Figure 1, it is shown as being formed integrally with the component body 31. The spacer portion 311 is a so-called convex portion. The shape of the spacer portion 311 may be disc-shaped as shown in Figure 2, but is not limited to a disc shape. Also, as shown in Figure 2, when the spacer portion 311 is viewed from above, the spacer portion 311 is located approximately in the center of the mounted component 3. From another perspective, the area occupied by the spacer portion 311 can be said to include the center of gravity 3G of the mounted component 3.

[0029] Refer to Figure 1 again. The bottom surface 31b1 of the spacer portion 311 is in contact with the resist layer 22. To describe the back surface 31b of the main body of the mounted component 3 in more detail, the back surface 31b of the main body includes a spacer bottom surface 31b1 that faces and is in contact with the substrate main surface facing region 22a1 of the resist layer 22, and a spacer peripheral surface 31b2 that faces the substrate main surface facing region 22a1 but is not in contact with the substrate main surface facing region 22a1.

[0030] The spacer portion 311 has a spacer thickness 311t defined as the length from the spacer peripheral surface 31b2 to the spacer bottom surface 31b1. This spacer thickness 311t is greater than the electrode thickness 322t of the component electrode 32, which will be described later. As a result, when the spacer bottom surface 31b1 is in contact with the substrate main surface facing region 22a1, a gap G (see Figure 4(b)) is formed between the substrate electrode 23 and the component electrode 32 during the assembly process of the mounting structure 10. The spacer portion 311 is intended to form this gap G.

[0031] The component electrode 32 includes a portion that covers the entire end face 31e of the main body (end face electrode portion 321), a portion that covers a portion of the back surface 31b of the main body (back surface electrode portion 322), a portion that covers a portion of the main surface 31a of the main body (main surface electrode portion 323), and a portion that covers a portion of the side surface 31s of the main body (side surface electrode portion 324). These four portions are formed integrally. The component electrode 32 protrudes from the surface of the component body 31. For example, the electrode thickness 322t of the back surface electrode portion 322 can be defined as the length from the back surface 31b of the main body to the surface of the back surface electrode portion 322. This electrode thickness 322t is assumed to be the "electrode thickness 322t of the component electrode 32" mentioned above.

[0032] The solder joint 4 serves both to physically fix the mounted component 3 to the substrate 2 and to electrically connect it. The solder joint 4 includes an end face solder fillet 41, a side solder fillet 42, and a solder layer 43. These together form the solder joint 4. The end face solder fillet 41 connects the main surface 23a of the substrate electrode to the end face electrode portion 321. The side solder fillet 42 connects the main surface 23a of the substrate electrode to the side electrode portion 324. The solder layer 43 connects the main surface 23a of the substrate electrode to the back surface electrode portion 322. The thickness of this solder layer 43 corresponds to the gap G formed by the spacer portion 311. Therefore, the spacer thickness 311t is equal to the sum of the electrode thickness 322t and the solder layer thickness 43t.

[0033] According to the inventors' investigation, the thickness of the solder layer 43 formed between the back electrode portion 322 and the main surface 23a of the substrate electrode (solder layer thickness 43t) affects the maximum value of the stress generated in the solder joint 4. Qualitatively, the thinner the solder layer thickness 43t, the greater the maximum value of the generated stress. This is thought to be because stress concentration occurs due to a large change in cross-sectional area between the solder layer 43 and the end face solder fillet 41. This solder layer thickness 43t is determined during the soldering process by the sinking of the mounted component 3 into the molten solder and the balance of surface tension. Therefore, when soldering without using a spacer portion, it was difficult to set the solder layer thickness 43t to the desired thickness.

[0034] Therefore, the inventors conceived of providing a portion for physically defining the gap between the back electrode portion 322 and the substrate electrode 23. The portion for physically defining the gap is a spacer portion 311 of the mounted component 3. The spacer portion 311 protrudes toward the substrate 2 side from the back electrode portion 322. As a result, when the bottom surface 31b1 of the spacer is in contact with the main surface 22a of the resist layer, a gap G is formed between the back electrode portion 322 and the substrate electrode 23. During soldering, molten solder enters this gap G, so a solder layer 43 corresponding to the length of the gap G can be formed. Therefore, if a solder layer thickness 43t can be set such that the maximum stress resulting from stress concentration is below the allowable stress value, the spacer thickness 311t can be determined using the solder layer thickness 43t and the electrode thickness 322t.

[0035] Next, the implementation method for obtaining the implementation structure 10 of the first embodiment will be explained with reference to the flowchart shown in Figure 3 and the process diagram shown in Figure 4. In the flowchart of Figure 3, the work constituting the implementation method is illustrated as "Step S". Furthermore, the state formed as a result of performing "Step S" is clearly indicated as "State C". Since State C is the result of performing Step S, it is not an element that constitutes the implementation method of the first embodiment.

[0036] First, prepare the mounting component 3 (step S11: see Figure 4(a)). In step S11, prepare the mounting component 3 that has the spacer portion 311 described above. Next, prepare the substrate 2 (step S12: see Figure 4(a)). In step S12, prepare the substrate 2 that does not have the spacer portion 311 described above.

[0037] Next, the mounted component 3, which is provided with the spacer portion 311, is placed on the substrate 2 (step S13: see Figure 4(b)). More specifically, the mounted component 3 is placed so that the spacer portion 311 is in contact with the main surface 22a of the resist layer between the pair of substrate electrodes 23. As a result, the bottom surface 31b1 of the spacer is in contact with the main surface 22a of the resist layer (state C131). Also, the back electrode portion 322 of the component electrode 32 is located on the substrate electrode 23. However, the back electrode portion 322 is not in contact with the substrate electrode 23, but is separated by a predetermined distance (state C132). This structure shown in Figure 4(b) is referred to as the solder preparation structure 10S.

[0038] Next, the component electrode 32 is soldered to the substrate electrode 23 (step S14: see Figure 4(c)). The specific soldering process is not particularly limited. For example, step S14 can be performed using reflow soldering, flow soldering, manual soldering, or soldering with a robot or other soldering iron.

[0039] Furthermore, the solder material used in step S14 is not particularly limited. For example, leaded solders such as eutectic solder and high-temperature solder, lead-free solders such as Sn-Ag-Cu solder and Sn-Bi solder can be used in step S14. Also, the form of the solder used in step S14 is not particularly limited. For example, various forms such as paste solder, solder wire, die-cut plate solder, and solder rods can be used in step S14.

[0040] The molten solder forms a fillet (C141) between the main surface 23a of the substrate electrode and the end surface electrode portion 321, and the back surface electrode portion 322 also forms a fillet (C142) between itself and the substrate electrode 23. The molten solder then enters the gap G between the main surface 23a of the substrate electrode and the back surface electrode portion 322. At this time, since the bottom surface 31b1 of the spacer is in contact with the main surface 22a of the resist layer, the gap G between the main surface 23a of the substrate electrode and the back surface electrode portion 322 is maintained even with the presence of the molten solder. Then, as the fillets formed in these areas solidify, the end surface solder fillet 41, the side surface solder fillet 42, and the solder layer 43 are formed.

[0041] As a result of performing the above steps S11, S12, S13, and S14, the mounting structure 10 of the first embodiment can be obtained.

[0042] Furthermore, the above-described implementation method may, if necessary, include a step after step S14 to remove the spacer portion 311 provided on the implementation component 3. If the spacer portion 311 is integrated with the component body 31, a mechanical method may be applied to remove the spacer portion 311. For example, mechanical methods include machining, extrusion and extraction using jigs or fluid / gripping mechanisms. If the spacer portion 311 is attached to the component body 31, chemical or thermal methods may be applied. A chemical method may include cleaning with a solvent. A thermal method may include heating the adhesive to melt it. After performing the step of removing the spacer portion 311, the implementation structure 10 described in the third embodiment below can be obtained.

[0043] <Effects and Effects> The mounting structure 10 for the mounted component 3 comprises a substrate 2, a mounted component 3 including a component body 31 and component electrodes 32 provided on the surface of the component body 31, which are fixed to the substrate electrodes 23 of the substrate 2 by solder, and a spacer portion 311 disposed between the main substrate surface 2a of the substrate 2 and the back surface 31b of the component body 31. The thickness 311t of the spacer portion 311 is greater than the thickness 322t of the component electrodes 32.

[0044] In this mounting structure 10, a spacer portion 311 with a thickness 311t greater than the thickness 322t of the component electrode 32 is placed between the main surface 2a of the substrate 2 and the back surface 31b of the mounted component 3. As a result, a gap G is formed between the component electrode 32 and the substrate electrode 23, corresponding to the difference between the thickness 322t of the component electrode 32 and the thickness 311t of the spacer portion 311. By forming a solder layer 43 in this gap G, the thickness 43t of the solder layer 43 does not become too thin. As a result, the degree of stress concentration that may occur in the solder layer 43 in environments with temperature changes is mitigated. Therefore, electrical connection failures are less likely to occur in solder joints 4 affected by thermal shock and thermal fatigue, and the mounted substrate 100 can continue to perform the desired functions required of it.

[0045] The mounting structure 10 further includes a solder layer 43 formed between the component electrode 32 and the substrate electrode 23. This structure makes it possible to form a solder layer 43 in which the degree of stress concentration is reduced.

[0046] The spacer portion 311 is a single protrusion positioned between the main surface 2a of the substrate and the back surface 31b of the main body. In a plan view, the area occupied by the spacer portion 311 includes the center of gravity 3G of the mounted component 3. This structure allows the mounted component 3 to be stabilized when it is placed on the substrate 2.

[0047] The spacer portion 311 is part of the mounted component 3 and protrudes from the back surface 31b of the main body of the mounted component 3. With this structure, a gap G between the component electrode 32 and the substrate electrode 23 can be formed simply by placing the mounted component 3 on the substrate 2.

[0048] The method for mounting the mounted component 3 includes the steps of: forming a solder preparation structure 10S in which a spacer portion 311 is placed between the main surface 2a of the substrate 2 and the back surface 31b of the mounted component 3, which includes the component body and the component electrodes 32 provided on the surface of the component body, thereby forming a gap between the substrate electrodes 23 of the substrate 2 and the component electrodes 32; and providing a solder joint 4 between the substrate electrodes 23 and the component electrodes 32. This mounting method makes it possible to form a solder layer 43 that can alleviate the degree of stress concentration. Therefore, electrical connection failures are less likely to occur in the solder joint 4 that is affected by thermal shock and thermal fatigue, and the mounted substrate 100 can continue to perform the desired functions required of it.

[0049] The process includes a step S11 in which a mounting component 3, including a spacer portion 311, is prepared before step S13 in which the solder preparation structure 10S is formed. According to step S11, a gap G between the component electrode 32 and the substrate electrode 23 can be formed simply by placing the mounting component 3 on the substrate 2.

[0050] <Second Embodiment> The mounting structure 10A of the second embodiment will be described with reference to Figure 5. In the first embodiment, the mounted component 3 had a spacer portion 311. In the second embodiment, the substrate 2A has a spacer layer 24.

[0051] The mounting structure 10A of the second embodiment includes a substrate 2A and a mounting component 3A. The mounting component 3A of the second embodiment is the same as the mounting component 3 of the first embodiment in all other respects, except that it does not have a spacer portion 311.

[0052] The substrate 2A of the second embodiment has a spacer layer 24. The spacer layer 24 is provided between a pair of substrate electrodes 23. The shape of the spacer layer 24 is, for example, a disc shape, but is not limited to this shape. Similar to the first embodiment, when the spacer layer 24 is viewed from above, the centroid 3G of the mounted component 3A overlaps with the area occupied by the spacer layer 24. The spacer layer 24 is provided on the main surface 21a of the substrate body. The spacer layer 24 is formed as a separate component from the resist layer 22. The main surface 21a of the substrate body includes a portion on which the resist layer 22 is provided and a portion on which the spacer layer 24 is provided.

[0053] The spacer layer 24 protrudes from the main surface 22a of the resist layer. In other words, the spacer layer thickness 24t of the spacer layer 24 is greater than the resist layer thickness 22t. Furthermore, the thickness 24t1 of the portion of the spacer layer 24 that protrudes from the resist layer 22 is greater than the back electrode thickness 322t. The difference between the thickness 24t1 of the portion protruding from the resist layer 22 and the back electrode thickness 322t corresponds to the gap G between the back electrode portion 322 and the substrate electrode 23.

[0054] Next, we will explain the implementation method for obtaining the implementation structure 10A of the second embodiment, referring to the flowchart shown in Figure 6 and the process diagram shown in Figure 7.

[0055] First, prepare the mounting component 3A (step S21: see Figure 7(a)). In step S21, prepare the mounting component 3A without the spacer layer 24. Next, prepare the substrate 2A (step S22: see Figure 7(a)). In step S22, prepare the substrate 2A with the aforementioned spacer layer 24.

[0056] Next, the mounted component 3A is placed on the substrate 2A on which the spacer layer 24 is provided (step S23: see Figure 7(b)). More specifically, the mounted component 3A is placed so that the main surface 24a of the spacer layer 24 is in contact with the back surface 31b of the main body. As a result, the main surface 24a of the spacer layer is in contact with the back surface 31b of the main body (state C231). The relationship between the component electrode 32 and the substrate electrode 23 is the same as in the first embodiment. That is, the back electrode portion 322 of the component electrode 32 is located on the substrate electrode 23. The back electrode portion 322 is not in contact with the substrate electrode 23, but is separated by a predetermined distance (state C232).

[0057] Then, the component electrode 32 is soldered to the substrate electrode 23 (step S24: see Figure 7(c)). Step S24 and the resulting states C241, C242, and C243 are the same as in the first embodiment.

[0058] As a result of performing the above steps S21, S22, S23, and S24, the mounting structure 10A of the second embodiment can be obtained.

[0059] In addition, as with the first embodiment, the above-described mounting method may optionally include a step of removing the spacer layer 24 provided on the substrate 2A after step S24. A mechanical method may be applied as the method for removing the spacer layer 24. For example, mechanical methods include machining, extrusion and extraction using jigs or fluid / gripping mechanisms. By performing the step of removing the spacer layer 24, the mounting structure 10A described in the third embodiment below can be obtained.

[0060] <Effects and Effects> In the mounting structure 10A, the spacer layer 24 is part of the substrate 2A and is a projection that protrudes from the main surface 2a of the substrate 2A. With this structure as well, a gap can be formed between the component electrode 32 and the substrate electrode 23 simply by placing the mounted component 3A on the substrate 2A.

[0061] In the above-described mounting structure 10A, the substrate 2A includes a substrate body 21, a resist layer 22 formed on the main surface of the substrate body 21, and a spacer layer 24 formed on the main surface of the substrate body 21. With this structure as well, a gap G between the component electrode 32 and the substrate electrode 23 can be formed simply by placing the mounted component 3A on the substrate 2A.

[0062] The mounting method further includes step S22 of preparing a substrate 2A including a spacer layer 24, prior to step S23 of forming the solder preparation structure 10S. This step S22 also allows the gap G between the component electrode 32 and the substrate electrode 23 to be formed simply by placing the mounted component 3A on the substrate 2A.

[0063] <Third Embodiment> The mounting structure 10B of the third embodiment will be described with reference to Figure 8. In the first embodiment, the mounted component 3 had a spacer portion 311. In the second embodiment, the substrate 2A had a spacer layer 24. In the third embodiment, neither the substrate 2B nor the mounted component 3B has a spacer portion. In the mounting structure 10B of the third embodiment, a spacer member 50 is present in part of its manufacturing steps, but the completed mounting structure 10B of the third embodiment shown in Figure 8 does not have a spacer member 50.

[0064] The mounting structure 10B of the third embodiment comprises a substrate 2B and mounted components 3B. The substrate 2B of the third embodiment is the same as the substrate 2 of the first embodiment. The mounted components 3B of the third embodiment are the same as the mounted components 3A of the second embodiment. The mounting structure 10B of the third embodiment has a solder joint 4. The solder joint 4 is also the same as the solder joint 4 of the first embodiment.

[0065] As shown in Figure 8, in the mounting structure 10B of the third embodiment, there is no spacer between the main surface 22a of the resist layer and the back surface 31b of the main body, resulting in a gap. The main surface 22a of the resist layer and the back surface 31b of the main body are parallel planes to each other.

[0066] Next, the implementation method for obtaining the implementation structure 10B of the third embodiment will be explained with reference to the flowchart shown in Figure 9 and the process diagrams shown in Figures 10 and 11.

[0067] First, prepare the mounting components 3B (step S31: see Figure 10(a)). This step S31 is the same as step S21 in the second embodiment. Next, prepare the substrate 2B (step S32: see Figure 10(a)). This step S32 is the same as step S12 in the first embodiment.

[0068] Next, a spacer member 50 is placed on the main surface 2a of the substrate (S33: see Figure 10(b)). The spacer member 50 is a thin, plate-shaped member. The spacer thickness 50t of the spacer member 50 may be the same as the spacer thickness 311t of the spacer portion 311 that the mounted component 3B of the first embodiment had. In other words, the spacer thickness 50t may be the sum of the thickness of the back electrode portion 322 and a predetermined solder layer thickness 43t.

[0069] Next, the mounting component 3B is placed on the substrate 2B on which the spacer member 50 is arranged (step S34: see Figure 10(c)). More specifically, the mounting component 3B is placed so that the main spacer surface 50a of the spacer member 50 is in contact with the back surface 31b of the main body. As a result, the main spacer surface 50a is in contact with the back surface 31b of the main body (state C341). The relationship between the component electrode 32 and the substrate electrode 23 is the same as in the first embodiment. That is, the back electrode portion 322 of the component electrode 32 is located on the substrate electrode 23. The back electrode portion 322 is not in contact with the substrate electrode 23, but is separated by a predetermined distance (state C342).

[0070] Next, the component electrode 32 is soldered to the substrate electrode 23 (step S35: see Figure 11(a)). Step S35 and the resulting states C351, C352, and C353 are the same as in the first embodiment.

[0071] Then, the spacer member 50 is removed (step S36: see Figure 11(b)). Mechanical methods may be applied to remove the spacer member 50. For example, mechanical methods include machining, and extrusion or extraction using jigs or fluid / gripping mechanisms.

[0072] <Effects and Effects> The mounting structure 10B for the mounted component 3B comprises a substrate 2B, a mounted component 3B which includes a component body 31 and a component electrode 32 provided on the surface of the component body 31 and is fixed to the substrate electrode 23 of the substrate 2B by a solder joint 4, and a solder layer 43 formed between the back surface of the component electrode 32 and the substrate electrode 23. The main surface 2a of the substrate includes a main surface facing region 22a1 that faces the back surface 31b of the component body. The back surface 31b of the component body includes a back surface 31b that faces the main surface facing region 22a1. The main surface facing region 22a1 of the substrate is parallel to the back surface 31b of the component body.

[0073] The solder layer 43 of the mounting structure 10B of the third embodiment has a solder layer thickness 43t that corresponds to the spacer thickness 50t of the spacer member 50 placed in step S33. Therefore, similar to the mounting structure 10 of the first embodiment, the degree of stress concentration that may occur in the solder layer 43 is mitigated, so that the mounting substrate 100 can continue to perform the desired functions required of it.

[0074] The spacer member 50 is a separate component from the substrate 2B and the mounted component 3B. The process further includes a step S33 in which the spacer member 50 is placed on the main surface 2a of the substrate before the step S34 in which the solder preparation structure 10S is formed, and a step S36 in which the spacer member 50 is removed from between the main surface 2a of the substrate and the component electrode 32 after the step S35 in which the solder joint 4 is provided. This step S36 makes it possible to obtain a mounted structure 10B in which the spacer member 50 does not remain.

[0075] <Variation> The mounting structure for the mounted component and the method for mounting the mounted component of the present invention are not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the present invention.

[0076] <First variation> As shown in Figure 12(a), the spacer portion 311C of the mounted component 3C may be composed of a plurality of protrusions 311a, 311b, 311c, and 311d. The shape of the plurality of protrusions 311a, 311b, 311c, and 311d when viewed from above may be circular or rectangular, as shown in Figure 12(b). When the plurality of protrusions 311a, 311b, 311c, and 311d are viewed from above, they are arranged so that the center of gravity 3G of the mounted component 3 is included in the region 311S formed by the plurality of protrusions 311a, 311b, 311c, and 311d, as shown in Figure 12(a).

[0077] In short, the spacer portion 311C of the mounting structure 10 of the first modified example includes a plurality of protrusions 311a, 311b, 311c, and 311d positioned between the main surface 2a of the substrate and the back surface 31b of the main body. In a plan view, the region 311S enclosed by the plurality of protrusions 311a, 311b, 311c, and 311d contains the center of gravity 3G of the mounted component 3. With this structure, the mounted component 3C can be stabilized when it is placed on the substrate 2.

[0078] <Second variation> As shown in Figure 13, the spacer layer 24D of the substrate 2D may be composed of a plurality of spacer layer protrusions 241a, 241b, 241c, and 241d. The shape of the spacer layer protrusions 241a, 241b, 241c, and 241d when viewed from above may be circular or rectangular, as shown in Figure 13. Also, similar to the first modified example, when the plurality of spacer layer protrusions 241a, 241b, 241c, and 241d are viewed from above, the center of gravity 3G of the mounted component 3 is included in the region formed by the plurality of spacer layer protrusions 241a, 241b, 241c, and 241d. This structure also allows the mounted component 3 to be stabilized when it is placed on the substrate 2.

[0079] <Note> This disclosure includes the following components.

[0080] This disclosure includes [1] "a substrate and, A mounting component comprising a component body and component electrodes provided on the surface of the component body, which is fixed to the substrate electrodes of the substrate by solder, It comprises a spacer portion disposed between the main surface of the substrate and the back surface of the component body, A mounting structure for mounted components, wherein the thickness of the spacer portion is greater than the thickness of the component electrode.

[0081] This disclosure is [2] "a mounting structure for a mounted component according to [1], further comprising a solder layer formed between the back surface of the component electrode and the substrate electrode."

[0082] This disclosure includes [3] "the spacer portion includes a plurality of protrusions arranged between the main surface of the substrate and the back surface of the main body, The mounting structure for the mounted component described in [1] or [2] above, wherein, when viewed from above, the region surrounded by the plurality of protrusions includes the center of gravity of the mounted component.

[0083] This disclosure includes [4] "the spacer portion includes a projection disposed between the main surface of the substrate and the back surface of the main body, The mounting structure according to [1] or [2] above, wherein, in a plan view, the area occupied by one of the protrusions includes the center of gravity of the mounted component.

[0084] This disclosure is [5] "a mounting structure for a mounting component according to any one of the above [1] to [4], wherein the spacer portion is a part of the mounting component and is a projection that protrudes from the back surface of the main body of the mounting component."

[0085] This disclosure is [6] "a mounting structure for a mounted component according to any one of the above [1] to [4], wherein the spacer portion is a part of the substrate and is a projection that protrudes from the main surface of the substrate."

[0086] This disclosure is [7] "a mounting structure for a mounted component according to any one of the above [1] to [4], comprising a substrate body, an insulating layer formed in a first region on the main surface of the substrate body, and a spacer layer which is the spacer portion formed in a second region on the main surface of the substrate body."

[0087] This disclosure includes [8] "a substrate and, A mounting component comprising a component body and component electrodes provided on the surface of the component body, and fixed to the substrate electrodes of the substrate by solder, The component electrode comprises a solder layer formed between the back surface of the component electrode and the substrate electrode, The main surface of the substrate includes a region facing the main surface of the substrate that faces the back surface of the main body, The back surface of the main body includes a component back surface facing region that faces the main surface facing region of the substrate, The mounting structure for the mounted component described in [1] above, wherein the region facing the main surface of the substrate is parallel to the region facing the back surface of the component.

[0088] This disclosure includes the steps of forming a solder preparation structure in which a spacer portion is arranged between the main surface of the substrate and the back surface of the mounted component, which includes the component body and component electrodes provided on the surface of the component body, and a gap is formed between the substrate electrodes of the substrate and the component electrodes, A method for mounting a component, comprising the step of providing a solder joint between the substrate electrode and the component electrode.

[0089] This disclosure includes

[10] "the spacer portion is a part of the mounting component, and is a projection that protrudes from the back surface of the main body of the mounting component, The method for mounting a component as described in [9] above, further comprising the step of preparing the mounting component including the spacer portion before the step of forming the solder preparation structure.

[0090] This disclosure includes

[11] "the spacer portion is a part of the substrate and is a projection that protrudes from the main surface of the substrate, The method for mounting components according to [9] above, further comprising the step of preparing the substrate including the spacer portion before the step of forming the solder preparation structure.

[0091] This disclosure includes

[12] "the spacer portion is a spacer member separate from the substrate and the mounted component, Prior to the step of forming the solder preparation structure, the step of placing the spacer member on the main surface of the substrate, The method for mounting a component as described in [9] above, further comprising the step of removing the spacer member from between the main surface of the substrate and the component electrode after the step of providing the solder joint. [Explanation of Symbols]

[0092] 10, 10A, 10B Implementation Structure 100 mounted circuit boards 10S Solder Preparation Structure 2,2A,2B,2D board 2a Main surface of the substrate 21a Main surface of the substrate 22. Resist layer (insulating layer) 22a Main surface of the resist layer 22a1 Substrate main surface facing region 22a2 Non-opposed area 22b Backside of the resist layer 23 Substrate electrodes 23a Main surface of substrate electrode 23b Back side of substrate electrode 24,24D Spacer layer 24a Main surface of spacer layer 3,3A,3B,3C mounted parts 3G center of gravity 31a Main body surface 31b Back of the main unit 31e Body end face 31s Side view of the main unit 31b1 Spacer bottom 31b2 Spacer surrounding surface 311 Spacer section 32 component electrodes 321 End electrode part 322 Backside electrode section 324 Side electrode part 4. Solder joint 41 End face solder fillet 42 Side solder fillets 43 Solder layers 50 Spacer member G Gap S Step Steps S11, S21, S31: Steps to prepare mounting components. Steps S12, S22, S32: Preparing the circuit board. S13, S23, S34 Steps for placing mounted components onto the circuit board. Steps S14, 24, and S35 involve soldering component electrodes to substrate electrodes. S33 Step of placing a spacer member on the main surface of the substrate. S36 Step to remove the spacer member

Claims

1. circuit board and A mounting component comprising a component body and component electrodes provided on the surface of the component body, which is fixed to the substrate electrodes of the substrate by solder, It comprises a spacer portion disposed between the main surface of the substrate and the back surface of the component body, A mounting structure for mounted components, wherein the thickness of the spacer portion is greater than the thickness of the component electrode.

2. The mounting structure for a mounted component according to claim 1, further comprising a solder layer formed between the back surface of the component electrode and the substrate electrode.

3. The spacer portion includes a plurality of protrusions arranged between the main surface of the substrate and the back surface of the main body, The mounting structure for a mounting component according to claim 1, wherein, in a plan view, the region surrounded by the plurality of protrusions includes the center of gravity of the mounting component.

4. The spacer portion includes a single projection positioned between the main surface of the substrate and the back surface of the main body, The mounting structure for a mounted component according to claim 1, wherein the region occupied by one of the protrusions in a plan view includes the center of gravity of the mounted component.

5. The mounting structure for a mounting component according to claim 1, wherein the spacer portion is a part of the mounting component and is a projection that protrudes from the back surface of the main body of the mounting component.

6. The mounting structure for a mounted component according to claim 1, wherein the spacer portion is a part of the substrate and is a projection that protrudes from the main surface of the substrate.

7. The mounting structure for a mounted component according to claim 1, wherein the substrate includes a substrate body, an insulating layer formed in a first region on the main surface of the substrate body, and a spacer layer which is the spacer portion formed in a second region on the main surface of the substrate body.

8. circuit board and A mounting component comprising a component body and component electrodes provided on the surface of the component body, and fixed to the substrate electrodes of the substrate by solder, The component electrode comprises a solder layer formed between the back surface of the component electrode and the substrate electrode, The main surface of the substrate includes a region facing the main surface of the substrate that faces the back surface of the main body, The back surface of the main body includes a component back surface facing region that faces the main surface facing region of the substrate, The mounting structure for a mounted component according to claim 1, wherein the region facing the main surface of the substrate is parallel to the region facing the back surface of the component.

9. The steps include forming a solder preparation structure in which a spacer portion is placed between the main surface of the substrate and the back surface of the mounted component, including the component body and the component electrodes provided on the surface of the component body, thereby forming a gap between the substrate electrodes of the substrate and the component electrodes, A method for mounting a component, comprising the step of providing a solder joint between the substrate electrode and the component electrode.

10. The spacer portion is a part of the mounted component, and is a projection that protrudes from the back surface of the main body of the mounted component. A method for mounting a mounting component according to claim 9, further comprising the step of preparing the mounting component including the spacer portion before the step of forming the solder preparation structure.

11. The spacer portion is a part of the substrate, and is a projection that protrudes from the main surface of the substrate. A method for mounting a component according to claim 9, further comprising the step of preparing the substrate including the spacer portion before the step of forming the solder preparation structure.

12. The spacer portion is a spacer member separate from the substrate and the mounted components. Prior to the step of forming the solder preparation structure, the step of placing the spacer member on the main surface of the substrate, A method for mounting a mounted component according to claim 9, further comprising the step of removing the spacer member from between the main surface of the substrate and the component electrode after the step of providing the solder joint.

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