Modules and electronic equipment

Abstract

To improve the reliability of solder joining in a module.SOLUTION: A module has a first printed circuit board, a second printed circuit board joined to the first printed circuit board via a plurality of first solder joining parts, a third printed circuit board joined to the second printed circuit board via a plurality of second solder joining parts, and first and second reinforcement resin parts. The second printed circuit board has a first side face and a second side face facing each other in a first direction. The first reinforcement resin part is attached to a principal surface of the first printed circuit board, the first side face of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of both ends in a second direction of the first side face of the second printed circuit board. The second reinforcement resin part is attached to the principal surface of the first printed circuit board, the second side face of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of both ends in the second direction of the second side face of the second printed circuit board.SELECTED DRAWING: Figure 4C

Description

Technical Field

[0001] The present invention relates to a module and an electronic device.

Background Art

[0002] In electronic devices, the communication speed of semiconductor devices and the density of mounting are increasing, and three-dimensional mounting technology for mounting a plurality of semiconductor devices and printed circuit boards in a stacked manner has become essential. A semiconductor device is a semiconductor package having a semiconductor element and an interposer, and is, for example, a digital signal processor or a memory. Also, a printed circuit board plays a role of electrically connecting these when, for example, a plurality of semiconductor devices are stacked.

[0003] In recent years, in semiconductor devices mounted on electronic devices such as mobile devices, high-speed and large-capacity data processing is performed, so the temperature rise during operation has become large. In such a semiconductor device, the stress applied to the solder joint due to thermal deformation has also increased. In particular, in a three-dimensional mounting structure in which semiconductor devices and printed circuit boards having different linear expansion coefficients are stacked on a printed wiring board, the risk of deterioration in the reliability of the solder joint may increase.

[0004] Therefore, in Patent Document 1, a mounting method is described in which reinforcing resin portions are formed at the peripheral portions of the four corners of a semiconductor device and a printed circuit board, and each thermal deformation is suppressed, thereby reducing the stress applied to the solder joint and improving the reliability of the solder joint. Specifically, the mounting method described in Patent Document 1 is a mounting method for a three-dimensional mounting structure in which a semiconductor device is mounted on a printed wiring board, resin is applied on the printed wiring board near the semiconductor device, and further a printed circuit board is mounted on the semiconductor device and reflow heated. According to the above method, it is said that the resin can be cured simultaneously with the solder joint by the reflow process, and the solder joint can be reinforced.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Publication No. 2015-50355 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, depending on the three-dimensional mounting structure, even if the resin is formed in a U-shape as described in Patent Document 1, stress may concentrate at the solder joints near the areas where the resin is not formed. For this reason, the mounting structure using the mounting method described in Patent Document 1 has the problem of not being able to obtain sufficient reinforcement effect and having insufficient solder joint reliability.

[0007] Therefore, the present invention aims to provide a module that can improve the reliability of solder joints. [Means for solving the problem]

[0008] According to one aspect of the present invention, the present invention comprises a first printed circuit board, a second printed circuit board disposed on the main surface of the first printed circuit board and joined to the first printed circuit board via a plurality of first solder joints, a third printed circuit board disposed on the side opposite to the second printed circuit board from the side of the first printed circuit board and joined to the second printed circuit board via a plurality of second solder joints, a first reinforcing resin portion, and a second reinforcing resin portion, wherein the second printed circuit board has first and second sides facing each other in a first direction, and a third side facing each other in a second direction intersecting the first direction. A module is provided having a surface and a fourth side surface, wherein the first reinforcing resin portion is attached to the main surface of the first printed circuit board, the first side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second side surface of the second printed circuit board in the second direction, and the second reinforcing resin portion is attached to the main surface of the first printed circuit board, the second side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second side surface of the second printed circuit board in the second direction.

[0009] According to another aspect of the present invention, the present invention comprises a first printed circuit board, a second printed circuit board disposed on the main surface of the first printed circuit board and joined to the first printed circuit board via a plurality of first solder joints, a third printed circuit board disposed on the side opposite to the second printed circuit board from the side of the first printed circuit board and joined to the second printed circuit board via a plurality of second solder joints, a first reinforcing resin portion, and a second reinforcing resin portion, wherein the second printed circuit board has first and second side surfaces facing each other in a first direction, and a third intersecting in the first direction A module is provided having a third side and a fourth side facing each other in two directions, wherein the first reinforcing resin portion is attached to the main surface of the first printed circuit board, the first side of the second printed circuit board, and the third printed circuit board, and is located away from the solder joint closest to the first reinforcing resin portion among the plurality of first solder joints and the plurality of second solder joints, and is attached to the solder joint closest to the first reinforcing resin portion among the other of the plurality of first solder joints and the plurality of second solder joints. [Effects of the Invention]

[0010] According to the present invention, the reliability of solder joints in modules can be improved. [Brief explanation of the drawing]

[0011] [Figure 1] This is a schematic diagram showing an example of an electronic device according to the first embodiment. [Figure 2] This is a perspective view showing a three-dimensional implementation structure according to the first embodiment. [Figure 3] This is a cross-sectional view showing a three-dimensional implementation structure according to the first embodiment. [Figure 4A] This is a top view showing an interposer in a three-dimensional mounting structure according to the first embodiment. [Figure 4B] This is a top view showing a printed circuit board in a three-dimensional mounting structure according to the first embodiment. [Figure 4C]It is a top view showing a three-dimensional mounting structure according to the first embodiment. [Figure 5A] It is a cross-sectional view showing a three-dimensional mounting structure according to the first embodiment. [Figure 5B] It is a cross-sectional view showing a three-dimensional mounting structure according to the first embodiment. [Figure 5C] It is a cross-sectional view showing a three-dimensional mounting structure according to the first embodiment. [Figure 5D] It is a side view showing a three-dimensional mounting structure according to the first embodiment. [Figure 5E] It is a cross-sectional view showing a three-dimensional mounting structure according to the first embodiment. [Figure 6A] It is a cross-sectional view showing a three-dimensional mounting structure according to the second embodiment. [Figure 6B] It is a cross-sectional view showing a three-dimensional mounting structure according to the second embodiment. [Figure 6C] It is a cross-sectional view showing a three-dimensional mounting structure according to the second embodiment. [Figure 7A] It is a cross-sectional view showing a three-dimensional mounting structure according to the third embodiment. [Figure 7B] It is a cross-sectional view showing a three-dimensional mounting structure according to the third embodiment. [Figure 8A] It is a cross-sectional view showing a three-dimensional mounting structure according to the fourth embodiment. [Figure 8B] It is a cross-sectional view showing a three-dimensional mounting structure according to the fourth embodiment. [Figure 9A] It is a top view showing a three-dimensional mounting structure according to the fifth embodiment. [Figure 9B] It is a side view showing a three-dimensional mounting structure according to the fifth embodiment. [Figure 10A] It is a top view showing a three-dimensional mounting structure according to the sixth embodiment. [Figure 10B] It is a side view showing a three-dimensional mounting structure according to the sixth embodiment. [Figure 10C] It is a plan view showing a solder joint in a three-dimensional mounting structure according to the sixth embodiment. [Figure 10D]This is a plan view showing the solder joints in a three-dimensional mounting structure according to the sixth embodiment. [Figure 11A] This graph shows the relationship between the length of resin coating and the stress applied to the solder joint. [Figure 11B] This graph shows the relationship between the resin coating length and solder joint reliability. [Figure 12A] This is a top view showing a three-dimensional implementation structure according to another embodiment. [Figure 12B] A side view showing a three-dimensional implementation structure according to another embodiment. [Figure 12C] This is a cross-sectional view showing a three-dimensional mounting structure according to another embodiment. [Modes for carrying out the invention]

[0012] [First Embodiment] A three-dimensional mounting structure, which is a module according to the first embodiment of the present invention, and an electronic device using the same will be described with reference to Figures 1 to 5E.

[0013] First, an example of an electronic device using the three-dimensional mounting structure according to this embodiment will be described with reference to Figure 1. Figure 1 is a schematic diagram showing a lens-interchangeable digital camera 600, which is an example of an electronic device using the three-dimensional mounting structure 500 according to this embodiment. In this embodiment, a lens-interchangeable digital camera 600 is described, but the digital camera 600 may be a lens-integrated type in which the lens is built into the camera body 601. Furthermore, the electronic device using the three-dimensional mounting structure 500 according to this embodiment is not limited to the digital camera 600 which is an imaging device, but may be any kind of device.

[0014] As shown in Figure 1, the digital camera 600 is, for example, a digital SLR camera, a digital mirrorless camera, or other interchangeable-lens digital camera, and comprises a camera body 601 and a lens unit 602 including a lens. The lens unit 602 is detachably attached to the camera body 601.

[0015] The camera body 601 comprises a housing 611, a three-dimensional mounting structure 500, and a sensor module 900. The three-dimensional mounting structure 500 and the sensor module 900 are processing modules, and are located inside the housing 611. The three-dimensional mounting structure 500 and the sensor module 900 are electrically connected to each other by flexible wiring 950. The flexible wiring 950 is, for example, a flexible cable or a flexible wiring board.

[0016] The sensor module 900 includes an image sensor 700, which is an image sensor, and a printed circuit board 800. The image sensor 700 is mounted on the printed circuit board 800. The image sensor 700 is, for example, a CMOS (Complementary Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor. The image sensor 700 has the function of converting light incident on it via the lens unit 602 into an electrical signal.

[0017] Next, the configuration of the three-dimensional mounting structure 500 according to this embodiment will be described using Figure 2. Figure 2 is a perspective view showing the three-dimensional mounting structure 500 according to this embodiment. In the following description, as shown in Figure 2, among the planar directions of the printed circuit board 100 described below, the direction parallel to one of the longitudinal directions of the reinforcing resin part 410 described below will be defined as the x-axis direction, and the direction perpendicular to the x-axis direction in the planar direction will be defined as the y-axis direction. Furthermore, the direction perpendicular to both the x-axis direction and the y-axis direction will be defined as the z-axis direction. The x-axis direction, y-axis direction, and z-axis direction do not necessarily have to be perpendicular to each other; they may be intersecting directions.

[0018] As shown in Figure 2, the three-dimensional mounting structure 500 includes a mounting structure 510, a printed circuit board 100, and a reinforcing resin part 410. The mounting structure 510 includes a semiconductor device 200. The reinforcing resin part 410 is made of resin 400. The mounting structure 510 is mounted on one of the main surfaces of the printed circuit board 100, which serves as the mounting surface. The printed circuit board 100 is, for example, a rigid substrate on which components are mounted.

[0019] The mounting structure 510 is a stacked structure comprising, for example, a semiconductor device 200 and a printed circuit board 300, with the printed circuit board 300 mounted on the semiconductor device 200 via solder joints 620 (see Figure 3). The semiconductor device 200 is, for example, a digital signal processor, which has the function of acquiring electrical signals from an image sensor 700, processing the acquired electrical signals to correct them, and generating image data. The printed circuit board 300 is, for example, a rigid substrate, on which components are mounted. The reinforcing resin part 410 is made of resin 400 and fixes the printed circuit board 100 and the mounting structure 510.

[0020] Next, the specific structure of the three-dimensional mounting structure 500 according to this embodiment will be described using Figures 3 to 5E. Figure 3 is a cross-sectional view showing the three-dimensional mounting structure 500 along line AA shown in Figure 2. Figures 4A to 4C are top views showing the interposer 220 of the semiconductor device 200, the printed circuit board 300, and the three-dimensional mounting structure 500, respectively. Figures 4A to 4C are top views viewed in the z-axis direction. Figures 5A to 5C and 5E are enlarged views showing an enlarged cross-section of the three-dimensional mounting structure 500 along line AA shown in Figure 2. Figure 5D is a side view showing the three-dimensional mounting structure 500. Figure 5D is a side view viewed in the y-axis direction.

[0021] The semiconductor device 200 is, for example, an area array semiconductor package, specifically a BGA (Ball Grid Array) semiconductor package. As shown in Figure 3, the semiconductor device 200 has semiconductor elements 210 and an interposer 220. The interposer 220 is, for example, a rigid substrate printed circuit board, on which components are mounted. The semiconductor elements 210 are mounted on the interposer 220.

[0022] As shown in Figure 4A, the interposer 220 has a rectangular planar shape when viewed from above in the z-axis direction, and sides 1, 2, 3, and 4 of the rectangular planar shape have sides 1a, 2b, 3c, and 4d, respectively. Sides 1 and 2 are opposite sides, and sides 3 and 4 are opposite sides. In the rectangular planar shape of the interposer 220 including sides 1, 2, 3, and 4, the length of the longer side is not particularly limited, but for example, it is 1.05 times or more, or 1 mm or more, the length of the shorter side. Sides 1a and 2b are end faces of the interposer 220 that are opposite each other in the y-axis direction. Sides 3c and 4d are end faces of the interposer 220 that are opposite each other in the x-axis direction. For example, the distance between side 1a and side 2b is smaller than the distance between side 3c and side 4d. In other words, of the sides 1, 2, 3, and 4 of the interposer 220, sides 1 and 2 may be the longer sides, and sides 3 and 4 may be the shorter sides. The distance between side 1a and side 2b, i.e., the lengths of side 3c and side 4d in the y-axis direction, is for example 5 to 50 mm, typically 10 to 30 mm, and preferably 10 to 20 mm. The distance between side 3c and side 4d, i.e., the lengths of side 1a and side 2b in the x-axis direction, is for example 5 to 50 mm, typically 10 to 30 mm, and preferably 10 to 20 mm. It is more effective to provide the reinforcing resin part 410 on the longer sides (sides 1 and 2) than on the shorter sides (sides 3 and 4).

[0023] As shown in Figure 3, the interposer 220 has an insulating substrate 230. The insulating substrate 230 has a main surface 231 and a main surface 232 on the opposite side of the main surface 231. The main surface 231 is the side on which the semiconductor element 210 is mounted (die bonded) and is the side opposite to the printed circuit board 100. The main surface 232 is the side facing the printed circuit board 100. The material of the insulating substrate 230 is, for example, glass epoxy. The semiconductor element 210 is made of, for example, silicon. The semiconductor element 210 only needs to be placed between the interposer 220 and the printed circuit board 300, and may be mounted (die bonded) on, for example, the main surface 332 on the side of the printed circuit board 300 facing the interposer 220.

[0024] The interposer 220 has a plurality of lands 241 arranged on the main surface 231 of the insulating substrate 230 and a plurality of lands 242 arranged on the main surface 232. The plurality of lands 241 are arranged on the main surface 231 in a peripheral arrangement pattern, for example, surrounding the outer periphery of the semiconductor element 210. The plurality of lands 242 may be arranged on the main surface 232 in a grid-like, i.e., matrix-like arrangement pattern, or in a staggered arrangement pattern. The lands 241 and lands 242 are terminals formed of a conductive metallic material, such as copper or gold.

[0025] Furthermore, the interposer 220 has solder resists 251 and 252. Specifically, solder resist 251 is provided on the main surface 231 of the insulating substrate 230. Solder resist 251 is a film made of solder resist material. Each of the multiple lands 241 is exposed by an opening formed in the solder resist 251. Also, solder resist 252 is provided on the main surface 232 of the insulating substrate 230. Solder resist 252 is a film made of solder resist material. Each of the multiple lands 242 is exposed by an opening formed in the solder resist 252. Lands 241 and 242 may be either SMD (Solder Mask Defined) or NSMD (Non-Solder Mask Defined) lands.

[0026] As shown in Figure 4B, the printed circuit board 300 has a rectangular planar shape when viewed from above in the z-axis direction, and sides 10, 20, 30, and 40 of the rectangular planar shape have sides 10a, 20b, 30c, and 40d, respectively. Sides 10 and 20 are opposite each other, and sides 30 and 40 are opposite each other. Sides 10, 20, 30, and 40 are located on the same side as sides 1, 2, 3, and 4 of the interposer 220 and the mounting structure 510, respectively. In the rectangular planar shape of the printed circuit board 300 including sides 10, 20, 30, and 40, the length of the longer side is not particularly limited, but is, for example, 1.2 to 1.6 times the length of the shorter side. Furthermore, the length of the longest side of the rectangular planar shape containing sides 10, 20, 30, and 40 is not particularly limited, but is, for example, 1.1 to 1.5 times the length of the side in the same direction of the rectangular planar shape containing sides 1, 2, 3, and 4 of the interposer 220. Sides 10a and 20b are end faces of the printed circuit board 300 that face each other in the y-axis direction. Sides 30c and 40d are end faces of the printed circuit board 300 that face each other in the x-axis direction.

[0027] For example, in the printed circuit board 300, the distance between side 30c and side 40d is greater than the distance between side 10a and side 20b. Also, for example, the distance between side 30c and side 40d in the printed circuit board 300 is greater than the distance between side 3c and side 4d in the interposer 220.

[0028] The printed circuit board 300 has an insulating substrate 330, as shown in Figure 3. The insulating substrate 330 has a main surface 331 and a main surface 332 opposite to the main surface 331. The main surface 331 is the surface opposite to the interposer 220 and faces outwards. The main surface 332 is the surface facing the interposer 220. The material of the insulating substrate 330 is, for example, glass epoxy.

[0029] The printed circuit board 300 has a plurality of lands 342 arranged on the main surface 332 of the insulating substrate 330. The plurality of lands 342 are arranged on the main surface 332 in an arrangement pattern corresponding to the arrangement pattern of the plurality of lands 241 in the interposer 220. The lands 342 are terminals formed of a conductive metallic material, such as copper or gold.

[0030] Furthermore, the printed circuit board 300 has solder resists 351 and 352. Specifically, solder resist 351 is provided on the main surface 331 of the insulating substrate 330. Solder resist 352 is provided on the main surface 332 of the insulating substrate 330. Solder resists 351 and 352 are films made of solder resist material. Each of the multiple lands 342 is exposed by an opening formed in the solder resist 352. The lands 342 may be either SMD or NSMD lands.

[0031] The printed circuit board 100 has an insulating substrate 130, as shown in Figure 3. The insulating substrate 130 has a main surface 131 on the side where the mounting structure 510 is mounted, and a main surface 132 on the opposite side from the main surface 131 that faces outwards. The material of the insulating substrate 330 is, for example, glass epoxy.

[0032] The printed circuit board 100 has a plurality of lands 141 arranged on the main surface 131 of the insulating substrate 130. The plurality of lands 141 are arranged on the main surface 131 in an arrangement pattern corresponding to the arrangement pattern of the plurality of lands 242 in the interposer 220. The lands 141 are terminals formed of a conductive metallic material, such as copper or gold.

[0033] Furthermore, the printed circuit board 100 has a solder resist 151. That is, a solder resist 151 is provided on the main surface 131 of the insulating substrate 130. The solder resist 151 is a film made of solder resist material. Each of the plurality of lands 141 is exposed by an opening formed in the solder resist 151. The lands 141 may be either SMD or NSMD lands.

[0034] Multiple lands 141 and multiple lands 242 are joined by solder joints 610 formed with solder. Similarly, multiple lands 241 and multiple lands 342 are joined by solder joints 620 formed with solder. The solder forming the solder joints 610 and 620 is, for example, solder balls. The arrangement of the solder joints 610 and 620 does not need to be vertically aligned when viewed from the x-axis and y-axis directions.

[0035] Thus, the interposer 220 is positioned on one side of the printed circuit board 100 and is joined to the printed circuit board 100 via a plurality of solder joints 610. The printed circuit board 300 is positioned on the side opposite to the printed circuit board 100 relative to the interposer 220 and is joined to the interposer 220 via a plurality of solder joints 620. The plurality of solder joints 610 are provided on at least sides 1, 2, 3, and 4 of the interposer 220. The plurality of solder joints 620 are also provided on at least sides 1, 2, 3, and 4 of the interposer 220. The plurality of solder joints 620 are arranged around the semiconductor element 210 on the side of the interposer 220 facing the printed circuit board 300.

[0036] As shown in Figure 4C, the interposer 220 and the printed circuit board 300, which are fixed to each other by solder joints 620, are arranged so that they overlap each other in a top view in the z-axis direction, with the printed circuit board 300 covering the interposer 220. In a top view, sides 10, 20, 30, and 40 of the rectangular shape of the printed circuit board 300 are located on the same side as sides 1, 2, 3, and 4 of the rectangular shape of the interposer 220 and the mounting structure 510, respectively. The rectangular shape of the interposer 220 may be the same shape and area as the rectangular shape of the printed circuit board 300, or it may be the same shape or a different shape with a smaller area. That is, in a top view, sides 1a, 2b, 3c, and 4d of the interposer 220 may be located in the same positions as sides 10a, 20b, 30c, and 40d of the printed circuit board 300, which are located on the same side of the mounting structure 510. Furthermore, in a top view, the sides 1a, 2b, 3c, and 4d of the interposer 220 may be located inward from the sides 10a, 20b, 30c, and 40d of the printed circuit board 300, which are located on the same side of the mounting structure 510. In other words, the sides 1a, 2b, 3c, and 4d of the interposer 220 may be located between the printed circuit board 100 and the printed circuit board 300 in the z-axis direction perpendicular to the main surface of the printed circuit board 100.

[0037] The reinforcing resin portion 410 is formed on the four sides 1, 2, 3, and 4 of the interposer 220 and the four sides 10, 20, 30, and 40 of the printed circuit board 300, as shown in Figure 4C, when the three-dimensional mounting structure 500 is viewed from above in the z-axis direction. This reinforcing resin portion 410 is made of resin 400. The reinforcing resin portion 410 can be formed by applying the uncured resin 400 to the area where the reinforcing resin portion 410 is to be formed and curing the resin 400. Although Figure 4C shows a case where the reinforcing resin portion 410 is formed in multiple parts on the four sides 10, 20, 30, and 40, some of the multiple reinforcing resin portions 410 may be integrated and continuous.

[0038] The semiconductor element 210 is provided in the y-axis direction between the reinforcing resin portion 410 formed on sides 1 and 10 and the reinforcing resin portion 410 formed on sides 2 and 20. Furthermore, the semiconductor element 210 is provided in the x-axis direction between the reinforcing resin portion 410 formed on sides 3 and 30 and the reinforcing resin portion 410 formed on sides 4 and 40.

[0039] For example, a thermosetting resin or an ultraviolet (UV) curing resin can be used for the resin 400. However, if a UV curing resin is used for the resin 400, depending on the relative sizes of the semiconductor device 200 and the printed circuit board 300 to be laminated, the UV light irradiated to cure the UV curing resin may not reach the resin, and the UV curing resin may not be cured. For this reason, a thermosetting resin is preferred for the resin 400 because it can be reliably cured by heating with a heating means such as an oven. Examples of constituent materials for a thermosetting resin include epoxy resin, filler, and curing agent. The heating temperature when curing the thermosetting resin as the resin 400 must be lower than the melting point of the solder joint 610, the melting point of the solder joint 620, and the heat resistance temperature of electronic components other than the semiconductor device 200 and the mounted structure 510 (not shown). It is preferable that the cured resin 400 has a flexural modulus of several tens of GPa to obtain a sufficient reinforcing effect.

[0040] In the above-described three-dimensional mounting structure 500, the printed circuit board 100, interposer 220, and printed circuit board 300, which are joined via solder joints 610 and 620, are fixed by reinforcing resin parts 410. The reinforcing resin parts 410 that fix these are formed as follows.

[0041] Figure 5A is an enlarged view of the cross-section along line AA in Figure 2, showing a cross-sectional view including side 1 of the interposer 220 and side 10 of the printed circuit board 300 as seen in the x-axis direction. The x-axis direction is parallel to the longitudinal direction of the reinforcing resin portion 410 provided on sides 1 and 10, i.e., parallel to sides 1 and 10.

[0042] As shown in Figure 5A, in the reinforcing resin portion 410, the resin 400 adheres to at least a portion of the printed circuit board 100 (e.g., a portion of the solder resist 151), a side surface 1a of the interposer 220, and a portion of the printed circuit board 300 (e.g., a portion of the solder resist 352). Here, the side surface 1a of the interposer 220 includes a portion (end) of the solder resist 251, a portion (end) of the solder resist 252, and a side surface (end face) of the insulating substrate 230. The resin 400 adhering to the printed circuit board 100, the interposer 220, and the printed circuit board 300 typically comes into contact with the printed circuit board 100, the interposer 220, and the printed circuit board 300. Typically, the resin 400 is formed to come into contact with the side of the printed circuit board 100 facing the interposer 220 and the side of the printed circuit board 300 facing the interposer 220. However, the resin 400 adhering to the printed circuit board 100, the interposer 220, and the printed circuit board 300 may come into contact with a coating or the like applied to at least one of the printed circuit boards 100, 220, and 300. In this way, the reinforcing resin portion 410 is adhering to the main surface of the printed circuit board 100, the side surface 1a of the interposer 220, and the printed circuit board 300. Furthermore, the resin 400 is formed to partially cover the end surface of the interposer 220, as will be described later.

[0043] In the example shown in Figure 5A, the reinforcing resin portion 410 is separated from the solder joint 610 closest to it among the multiple solder joints 610. It is also separated from the solder joint 620 closest to it among the multiple solder joints 620. Alternatively, as shown in Figure 5B, it is preferable that the resin 400 in the reinforcing resin portion 410 is in contact with the solder joint 610 located on the outermost periphery among the multiple solder joints 610, i.e., the solder joint 610 in the row closest to side 1. In other words, it is preferable that the reinforcing resin portion 410 is attached to the solder joint 610 closest to it among the multiple solder joints 610. This allows the resin 400 to more reliably fix the interposer 220 and the printed circuit board 100. Furthermore, it is preferable that the resin 400 is in contact with the solder joint 620 located on the outermost periphery of the plurality of solder joints 620, that is, the solder joint 620 in the row closest to the edge 10. In other words, it is preferable that the reinforcing resin portion 410 is attached to the solder joint 620 closest to the reinforcing resin portion 410 among the plurality of solder joints 620. This allows the resin 400 to more securely fix the interposer 220 and the printed circuit board 300.

[0044] Furthermore, the resin 400 in the reinforcing resin portion 410 is formed with a height of 421 in the z-axis direction. The height 421 is greater than or equal to the height from the main surface 131 side of the printed circuit board 100 to the main surface 332 side of the printed circuit board 300. In other words, the height 421 is greater than or equal to the height from the surface of the solder resist 151 of the printed circuit board 100 to the surface of the solder resist 352 of the printed circuit board 300.

[0045] Here, the resin 400 may be formed to reach the side surface 10a of the printed circuit board 300, as shown in Figure 5C. Furthermore, the resin 400 may be formed to reach the surface on the main surface 331 side, which is the side of the printed circuit board 300 opposite to the interposer 220, i.e., the surface of the solder resist 351. What is important here is that in the reinforcing resin portion 410, the resin 400 is in contact with the printed circuit board 100, the interposer 220, and the printed circuit board 300, and the resin 400 is fixed to each of them. Note that in the case shown in Figure 5C, the height of the reinforcing resin portion 410 in the z-axis direction is not particularly limited, and it is sufficient that it is attached to the side surface 10a of the printed circuit board 300. And when the reinforcing resin portion 410 is attached to the side surface 10a of the printed circuit board 300, the reinforcing resin portion 410 does not need to be attached to the main surface 331 and / or main surface 332 of the printed circuit board 300.

[0046] As shown in Figures 5A to 5C, in the side portion 511 of the mounting structure 510 provided with the reinforcing resin portion 410, the resin 400 is formed to cover the side surface of the interposer 220 between the printed circuit board 100 and the printed circuit board 300. The reinforcing resin portion 410 has a portion located between the printed circuit board 100 and the interposer 220 in the z-axis direction perpendicular to the main surface of the printed circuit board 100, and a portion located between the interposer 220 and the printed circuit board 300.

[0047] Figure 5D shows a side view of the reinforcing resin portion 410 provided on side 1 of the interposer 220 and side 10 of the printed circuit board 300, viewed in the y-axis direction. As shown in Figure 5D, the reinforcing resin portion 410 is separated from at least one of the two ends of the side surface 1a of the interposer 220 in the x-axis direction. That is, the resin 400 in the reinforcing resin portion 410 is formed such that at least one of the two ends of the side surface 1a of the interposer 220 in the x-axis direction is exposed from the reinforcing resin portion 410 without being covered by the resin 400. Furthermore, at least one of the two ends of the side surface 1a of the interposer 220 in the x-axis direction is exposed from the resin 400. Note that the ends of the side surface of the interposer 220 correspond to the corners of a quadrilateral formed by the four sides 1a, 1b, 1c, and 1d, and the ends of the side surface refer to the ends and the parts near the ends. At one end of side 1a and one end of side 3c, side 1a and side 3c are connected to each other, and at one end of side 2a and one end of side 4d, side 2a and side 4d are connected to each other. At the other end of side 1a and the other end of side 4d, side 1a and side 4d are connected to each other, and at the other end of side 3a and the other end of side 4d, side 3a and side 4d are connected to each other. Here, the reinforcing resin portion 410 has a length 411 in the x-axis direction. That is, on sides 1 and 10 where the reinforcing resin portion 410 is formed, the length 411 of the reinforcing resin portion 410 is shorter than the length of side 1 of the interposer 220. In other words, in the x-axis direction, which is the direction along the side portion 511 of the mounting structure 510 described later, the reinforcing resin portion 410 is shorter than the interposer 220. Here, it is preferable that the resin 400 in the reinforcing resin portion 410 is not covered by the resin 400 at both ends in the x-axis direction of the side surface 1a of the interposer 220, but is exposed from the reinforcing resin portion 410. This is because having the side surface 1a exposed at both ends, rather than just one end, allows for a better balance of the reinforcing effect of the reinforcing resin portion 410 with respect to the three-dimensional mounting structure 500.

[0048] On the other hand, when the reinforcing resin portion 410 is viewed in the y-axis direction, the solder joints 610 and 620 are covered by the resin 400 in the reinforcing resin portion 410 and are not exposed. However, as in the second embodiment described later, the solder joints 610 and 620 may be exposed from the resin 400 on both sides of the reinforcing resin portion 410 in the x-axis direction without being covered by the resin 400.

[0049] In addition, the above description focused on the reinforcing resin portion 410 provided on side 1 of the interposer 220 and side 10 of the printed circuit board 300, but other reinforcing resin portions 410 have the same configuration as described above. That is, the reinforcing resin portions 410 provided on sides 2 and 20 of the interposer 220 and printed circuit board 300 have the same configuration as the reinforcing resin portion 410 provided on sides 1 and 10. Furthermore, the reinforcing resin portions 410 provided on sides 3 and 30 and sides 4 and 40 of the interposer 220 and printed circuit board 300 have the same configuration as the reinforcing resin portion 410 provided on sides 1 and 10, except that the x-axis and y-axis directions are swapped.

[0050] Thus, in the three-dimensional mounting structure 500 according to this embodiment, reinforcing resin parts 410 are formed on each of the sides 511, 512, 513, and 514 of the mounting structure 510. Here, side 511 of the mounting structure 510 includes side 1 of the interposer 220 and side 10 of the printed circuit board 300. Side 512 includes side 2 of the interposer 220 and side 20 of the printed circuit board 300. Side 513 includes side 3 of the interposer 220 and side 30 of the printed circuit board 300. Side 514 includes side 4 of the interposer 220 and side 40 of the printed circuit board 300. If one or both sides 1a, 1b, 1c, 1d of the interposer 220 are exposed from the resin 400 at each side 511, 512, 513, 514, then part or all of the four corners of the interposer 220 are exposed from the resin 400. The reinforcing resin part 410 only needs to be provided on at least two of the side 511, 512, 513, 514 that are opposite each other.

[0051] The reinforcing resin portion 410 is provided such that it is separated from at least one end of the x-axis direction of side surface 1a of the interposer 220 and separated from at least one end of the x-axis direction of side surface 2b of the interposer 220. In this case, the end of side surface 1a from which the reinforcing resin portion 410 is separated may be closer to side surface 3d than to side surface 4d, and the end of side surface 2b from which the reinforcing resin portion 410 is separated may be closer to side surface 4d than to side surface 3c. In this way, by arranging exposed portions where the reinforcing resin portion 410 is not provided at diagonal corners of the rectangular planar shape of the interposer 220, the reinforcing effect of the resin 400 can be obtained more evenly.

[0052] Furthermore, the reinforcing resin portion 410 should be provided so as to be separated from one end and the other end of the x-axis direction of the side surface 1a of the interposer 220, and also separated from one end and the other end of the x-axis direction of the side surface 2b of the interposer 220.

[0053] The formation of the reinforcing resin portion 410 in this manner ensures that the reinforcing effect of the resin 400 is fully obtained. Furthermore, in the three-dimensional mounting structure 500, stress concentrates particularly in the solder joints 610 and 620 near areas where the resin 400 is not formed. However, by exposing part or all of the four corners of the interposer 220 from the resin 400, this stress concentration can be reduced. This is because the stress is distributed to the solder joints 610 and 620 near the four corners where the resin 400 is not formed. In addition, since the four corners of the interposer 220 are exposed from the resin 400 and not reinforced by the resin 400, if deformation occurs in the interposer 220 or the printed circuit board 300, that deformation can be relieved from the four corners. This allows for the reinforcement of the solder joints 610 and 620 while avoiding defects in the interposer 220 and the printed circuit board 300 due to deformation.

[0054] As described above, according to this embodiment, the reliability of solder joints in the three-dimensional mounting structure 500 can be improved.

[0055] Furthermore, regarding the thickness of the interposer 220 and the printed circuit board 300, as shown in Figure 5E, it is preferable that the thickness 301 of the printed circuit board 300 is smaller than the thickness 221 of the interposer 220. When the thickness 301 is smaller than the thickness 221, the rigidity of the printed circuit board 300 becomes relatively lower compared to the rigidity of the interposer 220. As a result, when the printed circuit board 300 deforms due to heat, the influence on the interposer 220, which has higher rigidity than the printed circuit board 300, is reduced. Consequently, the stress on the solder joints 610 and 620 in areas where the resin 400 is not formed is further reduced. Therefore, by making the thickness 301 thinner than the thickness 221, the reliability of the solder joints in the three-dimensional mounting structure 500 can be further improved.

[0056] Furthermore, the planar shapes of the interposer 220 and the printed circuit board 300 in a top view along the z-axis are not limited to rectangles, but may be polygons or other shapes that include the edges on which the reinforcing resin portion 410 is formed, as described above. In addition, the edges on which the reinforcing resin portion 410 is formed on the interposer 220 and the printed circuit board 300 may be straight or curved.

[0057] [Second Embodiment] A three-dimensional mounting structure 500 according to a second embodiment of the present invention will be described with reference to Figures 6A to 6C. Note that components similar to those in the first embodiment are denoted by the same reference numerals, and detailed descriptions are omitted or simplified.

[0058] The basic configuration of the three-dimensional mounting structure 500 according to this embodiment is the same as that of the three-dimensional mounting structure 500 according to the first embodiment. In the three-dimensional mounting structure 500 according to this embodiment, the relationship between the resin 400 of the reinforcing resin part 410 and the solder joints 610 and 620 differs from that of the first embodiment.

[0059] Figure 6A is a cross-sectional view of the three-dimensional mounting structure 500 according to this embodiment, and is a cross-sectional view corresponding to the cross-sectional view in Figure 3. Figure 6B is an enlarged view showing an enlarged cross-section of the three-dimensional mounting structure 500 according to this embodiment. Figure 6C is an enlarged view showing another example of a cross-section of the three-dimensional mounting structure 500 according to this embodiment. Figures 6B and 6C are enlarged views corresponding to Figure 5A, respectively, and show a cross-section including side 1 of the interposer 220 and side 10 of the printed circuit board 300 as viewed in the x-axis direction.

[0060] As shown in Figure 6A, in the three-dimensional mounting structure 500 according to this embodiment, the multiple lands 141 and the multiple lands 242 are joined by solder joints 610, similar to the first embodiment. Furthermore, the multiple lands 241 and the multiple lands 342 are joined by solder joints 620. Also, as shown in Figure 6C, in another example of the three-dimensional mounting structure 500 according to this embodiment, the multiple lands 141 and the multiple lands 242 are joined by solder joints 710. Furthermore, the multiple lands 241 and the multiple lands 342 are joined by solder joints 720.

[0061] As shown in Figures 6B and 6C, the solder joint 610 has a solder joint 610a located on the outermost periphery and a solder joint 610b located inside the solder joint 610a. The solder joint 620 has a solder joint 620a located on the outermost periphery and a solder joint 620b located inside the solder joint 620a. Also, as shown in Figure 6C, the solder joint 710 has a solder joint 710a located on the outermost periphery and a solder joint 710b located inside the solder joint 710a. The solder joint 720 has a solder joint 720a located on the outermost periphery and a solder joint 720b located inside the solder joint 720a.

[0062] Solder joints 610 and 710 are formed with a height of 616 in the z-axis direction. The height 616 is the height from the main surface 133 of the solder resist 151 to the main surface 234 of the solder resist 252. Solder joints 620 and 720 are formed with a height of 626 in the z-axis direction. The height 626 is the height from the main surface 233 of the solder resist 251 to the main surface 334 of the solder resist 352. The solder resist 251 has a thickness of 256. In addition, the solder resist 351 formed on the main surface 331 of the insulating substrate 330 in the printed circuit board 300 has a main surface 333.

[0063] The semiconductor element 210 may be mounted on the main surface 231 of the insulating substrate 230 as shown in Figures 6A and 6B, or on the main surface 232 of the insulating substrate 230 as shown in Figure 6C.

[0064] As shown in Figure 6B, when the semiconductor element 210 is mounted on the main surface 231 of the insulating substrate 230, the outermost position of the solder joint 610a in the y-axis direction is inward from the center position of the solder joint 620a in the y-axis direction. Also, as shown in Figure 6C, when the semiconductor element 210 is mounted on the main surface 232 of the insulating substrate 230, the outermost position of the solder joint 720a in the y-axis direction is located inward from the center position of the solder joint 710a in the y-axis direction.

[0065] The reinforcing resin portion 410 is formed on the four sides 1, 2, 3, and 4 of the interposer 220 and the four sides 10, 20, 30, and 40 of the printed circuit board 300, in a top view of the three-dimensional mounting structure 500 viewed from above in the z-axis direction, similar to the first embodiment.

[0066] In the three-dimensional mounting structure 500 according to this embodiment, as shown in Figure 6A, the printed circuit board 100, interposer 220, and printed circuit board 300, which are joined via solder joints 610 and 620, are fixed by the reinforcing resin part 410. Also, as shown in Figure 6C, the printed circuit board 100, interposer 220, and printed circuit board 300, which are joined via solder joints 710 and 720, are fixed by the reinforcing resin part 410.

[0067] As shown in Figures 6B and 6C, in the reinforcing resin portion 410, the resin 400 adheres to at least a part of the printed circuit board 100 (e.g., a part of the solder resist 151), the side surface 1a of the interposer 220, and a part of the printed circuit board 300 (e.g., a part of the solder resist 352). The resin 400 adhering to the printed circuit board 100, the interposer 220, and the printed circuit board 300 typically comes into contact with the printed circuit board 100, the interposer 220, and the printed circuit board 300. Typically, the resin 400 is formed to come into contact with the surface of the printed circuit board 100 on the side of the interposer 220 and the surface of the printed circuit board 300 on the side of the interposer 220. However, the resin 400 adhering to the printed circuit board 100, the interposer 220, and the printed circuit board 300 may come into contact with a coating or the like applied to at least one of the printed circuit board 100, the interposer 220, and the printed circuit board 300. Thus, the reinforcing resin portion 410 is attached to the main surface of the printed circuit board 100, the side surface 1a of the interposer 220, and the printed circuit board 300. In addition, the resin 400 is formed to partially cover the end surface of the interposer 220.

[0068] In this embodiment, as shown in Figure 6B, the resin 400 in the reinforcing resin portion 410 is in contact with the outermost solder joint portion 620a, but not with the outermost solder joint portion 610a. That is, the reinforcing resin portion 410 adheres to the solder joint portion 620a closest to the reinforcing resin portion 410 among the multiple solder joint portions 620, but does not adhere to the solder joint portion 610a closest to the reinforcing resin portion 410 among the multiple solder joint portions 610.

[0069] In the case shown in Figure 6B, the distance between the solder joint 610a closest to the reinforcing resin part 410 and the side surface 1a is longer than the distance between the solder joint 620a closest to the reinforcing resin part 410 and the side surface 1a.

[0070] Furthermore, the contact relationship between the resin 400 in the reinforcing resin portion 410 and the solder joints 610a and 620a may be the opposite of the relationship shown in Figure 6B. In other words, it is sufficient that one of the multiple solder joints 610 and multiple solder joints 620 has a relationship in which it adheres to the resin 400, while the other solder joint does not adhere to the resin 400. Specifically, as shown in Figure 6C, the resin 400 in the reinforcing resin portion 410 may be in contact with the outermost solder joint 710a, but not with the outermost solder joint 720a. That is, the reinforcing resin portion 410 may adhere to the solder joint 710a closest to the reinforcing resin portion 410 among the multiple solder joints 710, but not with the solder joint 720a closest to the reinforcing resin portion 410 among the multiple solder joints 720.

[0071] In the case shown in Figure 6C, the distance between the solder joint 720a closest to the reinforcing resin part 410 and the side surface 1a is longer than the distance between the solder joint 710a closest to the reinforcing resin part 410 and the side surface 1a.

[0072] Furthermore, the resin 400 in the reinforcing resin portion 410 formed on sides 2, 3, and 4 of the interposer 220 other than side 1, and on sides 20, 30, and 40 of the printed circuit board 300 other than side 10, may also be formed to have a relationship similar to that shown in Figure 6B or Figure 6C.

[0073] As the reinforcing resin portion 410 is formed in this manner, the reinforcing effect of the resin 400 is sufficiently obtained. Furthermore, if the resin 400 is not formed on all four sides of the interposer 220 and the printed circuit board 300, the reliability of the solder joint can be improved as follows. That is, as shown in Figure 6B, in a three-dimensional mounting structure 500 in which the resin 400 is not formed, the number of solder joints is less at the solder joint 620 on which the semiconductor element 210 is mounted than at the solder joint 610, so stress concentrates at the solder joint 620a. In contrast, if the reinforcing resin is formed on at least two opposing sides of the interposer 220 and the printed circuit board 300, the stress at the solder joint 620a is reduced. At this time, because the solder joint 610a on the side on which the resin 400 is formed is not in contact with the resin 400, the stress is distributed to the solder joint 610a that was not originally subjected to stress due to contact with the resin 400. Therefore, the stress on the solder joint 610a on the side where the resin 400 is formed increases, while the stress on the solder joint 620a on the side where the resin 400 is not formed decreases. This improves the solder joint reliability of the entire 3D mounting structure 500. Also, as shown in Figure 6C, in particular, in the 3D mounting structure 500 where the resin 400 is not formed, the number of solder joints is smaller in the solder joint 710 where the semiconductor element 210 is mounted than in the solder joint 720, so stress concentrates in the solder joint 710a. In contrast, when reinforcing resin is formed on at least two opposing sides of the interposer 220 and the printed circuit board 300, the stress on the solder joint 710a is reduced. At this time, because the solder joint 720a on the side where the resin 400 is formed is not in contact with the resin 400, the stress is distributed to the solder joint 720a that was not originally subjected to stress due to contact with the resin 400. Therefore, the stress on the solder joint 720a on the side where the resin 400 is formed increases, while the stress on the solder joint 710a on the side where the resin 400 is not formed decreases. This improves the solder joint reliability of the entire 3D mounting structure 500.

[0074] [Third Embodiment] A three-dimensional mounting structure according to the third embodiment of the present invention will be described with reference to Figures 7A and 7B. Note that components similar to those in the first and second embodiments are denoted by the same reference numerals, and detailed descriptions are omitted or simplified.

[0075] The basic configuration of the three-dimensional mounting structure 500 according to this embodiment is the same as that of the three-dimensional mounting structure 500 according to the second embodiment. The three-dimensional mounting structure 500 according to this embodiment differs from the second embodiment in that a recessed step is formed in the portion of the interposer 220 that is outside the solder joint portion 620a.

[0076] Figure 7A is a cross-sectional view showing the three-dimensional mounting structure 500 according to this embodiment, and is a cross-sectional view corresponding to the cross-sectional view in Figure 6B. As shown in Figure 7A, in this embodiment, a portion of the main surface 231 of the insulating substrate 230 located outside the solder joint 620a at the outermost periphery is removed, and a recessed step 260 is formed. A reinforcing resin portion 410 is formed on top of the step 260. The range of the step 260 formed outside the plurality of solder joints 620 in this way extends in a rectangular ring shape in the x-axis and y-axis directions so as to surround the outermost periphery of the solder joint 620a. The step 260 has a height of 266. The step 260 may reach the end of the interposer 220, or it may be formed between the solder joint 620a and the end of the interposer 220. In this case, the height between the interposer 220 and the printed circuit board 300 is a height of 628 in the z-axis direction in the portion where the step 260 is located. The height 628 is the height from the main surface 231 of the step 260 of the insulating substrate 230 to the main surface 234 of the solder resist 352.

[0077] In the area where the reinforcing resin portion 410 is formed and there is a step 260, the resin 400 of the reinforcing resin portion 410 penetrates. Due to the presence of this step 260, the height 628 to which the resin 400 penetrates is higher than the height 626 shown in Figure 6B where the step 260 does not exist, by the height 266 of the step 260. Thus, when there is a step 260, the height to which the resin 400 penetrates is higher, making it easier for the resin 400 to penetrate.

[0078] Furthermore, the step 260 does not necessarily have to be formed by the removal of a portion of the insulating substrate 230. Figure 7B is a cross-sectional view showing another example of the step 260. For example, as shown in Figure 7B, the step 260 may be formed as an opening 255 created by removing a portion of the solder resist 251 provided on the main surface 231 of the insulating substrate 230, specifically the portion located outside the outermost solder joint 620a. In this case, the height between the interposer 220 and the printed circuit board 300 is a height 627 in the z-axis direction in the portion where the opening 255 is located. The height 627 is the height from the main surface 231 of the insulating substrate 230 to the main surface 234 of the solder resist 352.

[0079] As in this embodiment, a step 260 may be provided on the outside of the solder joint 620a located on the outermost periphery, and the resin 400 of the reinforcing resin part 410 may be formed to fit into the step 260. This makes it easier for the resin 400 of the reinforcing resin part 410 to fit between the interposer 220 and the printed circuit board 300, and allows the resin 400 to come into more reliable contact with the solder joint 620a.

[0080] In addition, the three-dimensional mounting structure 500 according to the first embodiment may also be provided with a step 260, similar to this embodiment.

[0081] [Fourth Embodiment] A three-dimensional mounting structure 500 according to the fourth embodiment of the present invention will be described with reference to Figures 8A and 8B. Note that components similar to those in the first to third embodiments are denoted by the same reference numerals, and detailed descriptions are omitted or simplified.

[0082] The basic configuration of the three-dimensional mounting structure 500 according to this embodiment is the same as that of the three-dimensional mounting structure 500 according to the second embodiment. The three-dimensional mounting structure 500 according to this embodiment differs from the second embodiment in that a dummy bump 650, which is a solder portion, is provided on the outside of the solder joint portion 610a located on the outermost periphery.

[0083] Figure 8A is a cross-sectional view showing the three-dimensional mounting structure 500 according to this embodiment, and is a cross-sectional view corresponding to the cross-sectional view in Figure 6A. As shown in Figure 8A, the printed circuit board 100 has lands 143 arranged on the outer periphery of lands 141 on the main surface 131. The interposer 220 also has lands 244 arranged on the outer periphery of lands 242 on the main surface 232 of the insulating substrate 230. Dummy bumps 650, which are solder parts, are mounted on lands 244. The height of the dummy bumps 650 is lower than the height 616 (see Figure 6B) and is not joined to the lands 143. Therefore, there is an air gap between the dummy bumps 650 and the printed circuit board 100.

[0084] Figure 8B is a cross-sectional view showing another example of the dummy bump 650. As shown in Figure 8B, the dummy bump 650 may be mounted on the land 143 on the printed circuit board 100 side, rather than on the land 244 on the interposer 220 side. In this case, a gap exists between the dummy bump 650 and the interposer 220.

[0085] Thus, the dummy bump 650 provided between the printed circuit board 100 and the interposer 220 is provided so as not to be joined to either the printed circuit board 100 or the interposer 220. The reinforcing resin part 410 is attached to the dummy bump 650.

[0086] As described above, the provision of the dummy bump 650 prevents the resin 400 of the reinforcing resin portion 410 from penetrating into the mounting structure 510. As a result, in the three-dimensional mounting structure 500 according to this embodiment, the resin 400 is formed so as not to come into contact with the solder joint portion 610a located on the outermost periphery, similar to the second embodiment.

[0087] Furthermore, as shown in Figure 6C, if the semiconductor element 210 is mounted on the main surface 232 of the insulating substrate 230, the dummy bump 650 may be provided outside the solder joint 720a rather than outside the solder joint 710a.

[0088] Furthermore, in the three-dimensional mounting structure 500 according to the first or third embodiment, dummy bumps 650 may also be provided, similar to this embodiment.

[0089] [Fifth Embodiment] A three-dimensional mounting structure according to the fifth embodiment of the present invention will be described with reference to Figures 9A and 9B. Figure 9A is a top view showing the three-dimensional mounting structure according to this embodiment. Figure 9B is a side view of the three-dimensional mounting structure 500 according to this embodiment as seen from the y-axis direction. Components similar to those in the first to fourth embodiments are denoted by the same reference numerals, and detailed descriptions are omitted or simplified.

[0090] As shown in Figures 9A and 9B, this embodiment shortens the length 411 of the reinforcing resin portion 410 in the x-axis direction, which is the direction along the side portion 511 of the mounting structure 510 on which the reinforcing resin portion 410 is provided, compared to the first embodiment. As shown in Figure 9B, in this embodiment, the reinforcing resin portion 410 is provided at a position that overlaps with the projected semiconductor element 210 when the semiconductor element 210 is projected in the y-axis direction. That is, in a side view of the side portion 511 of the mounting structure 510, the reinforcing resin portion 410 is provided so as to include the region where the semiconductor element 210 and the solder joint portion 620 overlap. As shown in Figure 9B, in this embodiment, the reinforcing resin portion 410 is provided at a position that overlaps with the projected semiconductor element 210 when the semiconductor element 210 is projected in the y-axis direction. In other words, in a side view of the side portion 511 of the mounting structure 510, the reinforcing resin portion 410 is provided such that it includes an area where the semiconductor element 210 and the solder joint portion 620 overlap.

[0091] In a side view of the side portion 511 of the mounting structure 510, the outermost solder joint 610 of the multiple solder joints 610 is located at the same position as the outermost solder joint 620 of the multiple solder joints 620, but this is not limited to this. In a side view of the side portion 511 of the mounting structure 510, the outermost solder joint 610 of the multiple solder joints 610 may be located inward from the outermost solder joint 620 of the multiple solder joints 620.

[0092] In the x-axis direction, which is along the side portion 511 of the mounting structure 510, the length 411 of the reinforcing resin portion 410 is longer than the length of the semiconductor element 210, i.e., the length 211 of the projected side of the semiconductor element 210. Thus, in the x-axis direction, the length 411 of the reinforcing resin portion 410 may be shorter than in the first embodiment, as long as it is longer than the length 211 of the side of the semiconductor element 210. With the length 411 of the reinforcing resin portion 410 being shorter in this way, when the reinforcing resin portion 410 is viewed from the y-axis direction, the solder joints 610 and 620 may be exposed from the resin 400 on both sides of the reinforcing resin portion 410 in the x-axis direction without being covered by the resin 400.

[0093] Thus, in this embodiment, at both ends of the side portion 511 of the mounting structure 510 provided with the reinforcing resin portion 410, the outermost solder joints 610 among the plurality of solder joints 610 are exposed from the resin 400. That is, the reinforcing resin portion 410 is separated from the solder joints 610 that are closest to one end and the other end of the side surface 1a of the interposer 220 in the x-axis direction. Note that at one end of the side portion 511 of the mounting structure 510, the plurality of solder joints 610 that are located on the outermost periphery among the plurality of solder joints 610 may be exposed from the resin 400. In this example, among the solder joints 610 located on the outermost periphery, the first three solder joints 610 that are closest in distance from one end of the side surface 1a of the interposer 220 in the x-axis direction are exposed from the resin 400. The same applies to the other end of the side surface 1a of the interposer 220 in the x-axis direction. Furthermore, at both ends of the side portion 511 of the mounting structure 510, the outermost solder joints 620 among the multiple solder joints 620 are exposed from the resin 400. That is, the reinforcing resin portion 410 is separated from the solder joints 620 that are closest to one end and the other end of the side surface 1a of the interposer 220 in the x-axis direction. Note that at one end of the side portion 511 of the mounting structure 510, the multiple solder joints 620 that are closest to the outermost solder joints 620 are exposed from the resin 400. In this example, among the outermost solder joints 610, the first three solder joints 620 that are closest to one end of the side surface 1a of the interposer 220 in the x-axis direction are exposed from the resin 400. The same applies to the other end of the side surface 1a of the interposer 220 in the x-axis direction.

[0094] In addition, the above description focused on the reinforcing resin portion 410 provided on side 1 of the interposer 220 and side 10 of the printed circuit board 300. However, as shown in Figure 9A, other reinforcing resin portions 410 may have a similar configuration. That is, the reinforcing resin portions 410 provided on sides 2 and 20 of the interposer 220 and printed circuit board 300 may have a similar configuration to the reinforcing resin portion 410 provided on sides 1 and 10. Furthermore, the reinforcing resin portions 410 provided on sides 3 and 30 and sides 4 and 40 of the interposer 220 and printed circuit board 300 may have a similar configuration to the reinforcing resin portion 410 provided on sides 1 and 10, except that the x-axis and y-axis directions are reversed.

[0095] In this embodiment as well, the stress distribution effect described in the first embodiment, namely the effect of distributing stress to the solder joints 610 and 620 near the four corners where the reinforcing resin portion 410 is not formed, can be sufficiently obtained. Furthermore, since the reinforcing resin portion 410 is provided to include the region where the semiconductor element 210 and the solder joint 620 overlap, the solder joint at the point where the stress is most concentrated can be reinforced. In this way, by applying the resin for at least a length longer than the semiconductor element and exposing the edges of the interposer's sides from the resin, the reliability of the solder joints of the three-dimensional mounting structure can be improved. Therefore, according to this embodiment, the reliability of the solder joints in the three-dimensional mounting structure 500 can be sufficiently maintained. Furthermore, by shortening the length of the resin within the range described in this embodiment and reducing the amount of resin applied compared to the first embodiment, the cost of the resin can be reduced.

[0096] In addition, in the three-dimensional mounting structure 500 according to the second, third, or fourth embodiment, the length 411 of the reinforcing resin portion 410 may be shortened, similar to this embodiment.

[0097] [Sixth Embodiment] A three-dimensional mounting structure 500 according to the sixth embodiment of the present invention will be described with reference to Figures 10A to 10D. Figure 10A is a top view showing the three-dimensional mounting structure 500 according to this embodiment. Figure 10B is a side view of the three-dimensional mounting structure 500 according to this embodiment as seen from the y-axis direction. Figure 10C is a plan view showing the solder joint 610. Figure 10D is a plan view showing the solder joint 620. Note that components similar to those in the first to fifth embodiments are denoted by the same reference numerals, and detailed descriptions are omitted or simplified.

[0098] In the first to fifth embodiments, reinforcing resin portions 410 were formed on each of the four sides of the mounting structure 510 corresponding to the four sides of the interposer 220 and the four sides of the printed circuit board 300. In contrast, in this embodiment, the sides of the mounting structure 510 that form the reinforcing resin portions 410 are limited to two of the four sides. In this embodiment, the structure of the reinforcing resin portions 410 formed on the two sides and their surrounding structures can be the same as in any of the first to fifth embodiments.

[0099] As shown in Figure 10A, in this embodiment, reinforcing resin portions 410 are formed on two opposing sides 511 and 512 of the mounting structure 510. Side 511 of the mounting structure 510 includes side 1 of the interposer 220 and side 10 of the printed circuit board 300. Side 512 of the mounting structure 510 includes side 2 of the interposer 220 and side 20 of the printed circuit board 300.

[0100] On the other hand, the reinforcing resin portion 410 is not formed on the two opposing sides 513 and 514 of the mounting structure 510. Side 513 of the mounting structure 510 includes side 3 of the interposer 220 and side 30 of the printed circuit board 300. Side 514 of the mounting structure 510 includes side 4 of the interposer 220 and side 40 of the printed circuit board 300. In other words, the sides 3c and 4c of the interposer 220 do not have resin portions made of the same material as the reinforcing resin portion 410 attached to them.

[0101] In this embodiment, for example, sides 10 and 20 of the printed circuit board 300 are approximately 1.1 times longer than sides 1 and 2 of the interposer 220, and sides 30 and 40 of the printed circuit board 300 are approximately the same length as sides 3 and 4 of the interposer 220. That is, sides 3 and 4 of the interposer 220 are hidden beneath the printed circuit board 300, where sides 30 and 40 are located outside the interposer 220. In this case, as shown in Figure 10A, reinforcing resin parts 410 are formed on two opposing sides 511 and 512 of the mounting structure 510. Side 511 includes side 1 of the interposer 220 and side 10 of the printed circuit board 300. Side 512 includes side 2 of the interposer 220 and side 20 of the printed circuit board 300. Furthermore, as shown in Figure 10B, when the three-dimensional mounting structure 500 is viewed from the y-axis direction, the solder joints 610 on the side portion 511 are hidden and not visible by the reinforcing resin portion 410. On the other hand, the outermost solder joint 620 of the multiple solder joints 620 is positioned outside the outermost solder joint 610 of the multiple solder joints 610, and is exposed at one point from each end of the reinforcing resin portion 410. The side portion 512 of the mounting structure 510 has the same configuration as described above. This allows the stress concentrated in the solder joints 610 near the side portions 513 and 514 to be distributed to the solder joints 620 exposed from both ends of the resin on the side portions 511 and 512. Therefore, according to this embodiment, the reliability of the solder joints of the three-dimensional mounting structure 500 can be improved compared to the case where the reinforcing resin portion 410 is formed on the two sides of the mounting structure 510 so as to cover sides 1 and 2 of the interposer 220.

[0102] Furthermore, depending on the production cycle, it may be necessary to shorten the time required to apply the resin 400. In such cases, by forming the reinforcing resin portion 410 on the two side portions 511 and 512 of the mounting structure 510, as in this embodiment, the time required to apply the resin 400 can be shortened while ensuring sufficient reliability of the solder joint.

[0103] Here, Figures 10C and 10D show the arrangement of the solder joints 610 and 620 as viewed from the z-axis direction. Let L1 be the distance between the solder joint 610 closest to one end of the side surface 1a in the x-axis direction and the solder joint 610 closest to the other end of the side surface 1a in the x-axis direction. Let L2 be the distance between the solder joint 620 closest to one end of the side surface 1a in the x-axis direction and the solder joint 620 closest to the other end of the side surface 1a in the x-axis direction. Then, distance L2 may be greater than distance L1.

[0104] Furthermore, the solder joints 610 or 620 may not be arranged in an equal number of rows on the four sides 511, 512, 513, and 514 of the mounted structure 510, but rather on two opposing sides with fewer rows. In this case, it is preferable that the reinforcing resin portion 410 is formed on the two sides with fewer rows of solder joints 610 or 620. This is because areas with fewer rows of solder joints are more prone to fracture when stress is concentrated than areas with more rows, and by preferentially forming the reinforcing resin portion 410 on these areas to reduce stress, the reinforcing effect is effectively achieved. For example, multiple solder joints 610 or multiple solder joints 620 may be arranged in fewer rows on the sides 511 and 512 where the reinforcing resin portion 410 is provided than on the sides 513 and 514 where the reinforcing resin portion 410 is not provided. Here, let S1 be the sum of the number of solder joints 620 located between the semiconductor element 210 and the side surface 1a of the interposer 220 in the y-axis direction and the number of solder joints 620 located between the semiconductor element 210 and the side surface 2b of the interposer 220 in the y-axis direction. Also, let S2 be the sum of the number of solder joints 620 located between the semiconductor element 210 and the side surface 3c of the interposer 220 in the x-axis direction and the number of solder joints 620 located between the semiconductor element 210 and the side surface 4d of the interposer 220 in the x-axis direction. Then, in the example above where there is a difference in the number of columns, the sum S1 is smaller than the sum S2.

[0105] [Examples] (Example 1) Example 1, corresponding to the first embodiment, will be described. The dimensions of each part of the 3D mounting structure 500 were as follows: The interposer 220 had sides 1 and 2 each measuring 16.40 mm, and sides 3 and 4 each measuring 15.20 mm. The thickness of the interposer 220, including solder masks 251 and 252, was approximately 0.50 mm, and the thickness of solder masks 251 and 252 was approximately 0.015 mm each. The printed circuit board 300 had sides 10 and 20 each measuring 22.0 mm, and sides 30 and 40 each measuring 15.8 mm. The thickness of the printed circuit board 300, including solder masks 351 and 352, was approximately 0.37 mm, and the thickness of solder masks 351 and 352 was approximately 0.016 mm each.

[0106] The solder joints 610 were arranged in a staggered pattern with a pitch of 0.40 mm. The solder joints 620 were also arranged in a staggered pattern with a pitch of 0.60 mm, surrounding the outer periphery of the semiconductor element 210. With the solder joints 620 formed, the height from the surface of the solder resist 151 on the printed circuit board 100 to the solder resist 352 on the printed circuit board 300 was approximately 0.90 mm.

[0107] In the above-described three-dimensional mounting structure 500, resin 400 was applied to sides 1, 2, 3, and 4 of the interposer 220 and sides 10, 20, 30, and 40 of the printed circuit board 300. During the application of resin 400, the resin 400 was dispensed from a nozzle attached to a dispenser (not shown) while it was being moved.

[0108] Next, the three-dimensional mounting structure 500 coated with resin 400 was placed in an oven (not shown) and heated to cure the resin 400, forming a reinforcing resin part 410 made of the cured resin 400. The curing conditions in the oven were a temperature of 125°C and a time of 30 minutes.

[0109] The reinforcing resin portion 410 thus formed had a length of approximately 15.00 mm, a width of approximately 1.60 mm, and a height of approximately 1.20 mm. That is, at the four sides 511, 512, 513, and 514 of the mounting structure 510 on which the reinforcing resin portion 410 was formed, the length of the reinforcing resin portion 410 was shorter than sides 1, 2, 3, and 4 of the interposer 220. In addition, the sides 1a, 1b, 1c, and 1d of the interposer 220 were exposed from both ends of the reinforcing resin portion 410.

[0110] As described above, by forming the reinforcing resin portion 410, the reliability of the solder joints in the three-dimensional mounting structure 500 was improved in Example 1.

[0111] (Example 2) Example 2, which corresponds to both the first and sixth embodiments, will now be described. The dimensions of each part of the 3D mounting structure 500 were as follows: The outer dimensions of the printed circuit board 300 were such that the lengths of sides 10 and 20 were 21.45 mm each, and the lengths of sides 30 and 40 were 15.40 mm each. The thickness of the printed circuit board 300, including the solder resists 351 and 352, was approximately 0.37 mm, and the thickness of the solder resists 351 and 352 was approximately 0.016 mm each. Of the outermost solder joints 610, the distance between the solder joints 610 at both ends near sides 511 and 512 of the mounting structure 510 was approximately 14.9 mm. Of the outermost solder joints 620, the distance from end to end between the solder joints 620 at both ends near sides 511 and 512 was approximately 15.9 mm.

[0112] Furthermore, the reinforcing resin portion 410 was formed on a side portion 511 including side 1 of the interposer 220 and side 10 of the printed circuit board 300, and on a side portion 512 including side 2 of the interposer 220 and side 20 of the printed circuit board 300. The reinforcing resin portion 410 had a length of approximately 15.00 mm, a width of approximately 1.60 mm, and a height of approximately 1.20 mm.

[0113] Other aspects, such as the length of the sides of the interposer 220 and the height from the surface of the solder resist 151 on the printed circuit board 100 to the solder resist 352 on the printed circuit board 300, were the same as in Example 1.

[0114] In the two side portions 511 and 512 of the mounting structure 510 on which the reinforcing resin portion 410 was formed, the length of the reinforcing resin portion 410 was shorter than the sides 1 and 2 of the interposer 220. Also, the sides 1a and 2a of the interposer 220 were exposed from both ends of the reinforcing resin portion 410. Furthermore, the solder joint portion 610 was hidden from view by the reinforcing resin portion 410, while the solder joint portion 620 had one joint at each end exposed from the reinforcing resin portion 410.

[0115] As described above, by forming the reinforcing resin portion 410, the reliability of the solder joints in the three-dimensional mounting structure 500 was improved in Example 2 as well.

[0116] Next, in the 3D mounting structure 500, a simulation was performed to examine the relationship between the length of the resin 400 applied to the side portion 511 including sides 1 and 10 of the mounting structure 510, and the side portion 512 including sides 2 and 20, and the stress applied to the solder joints 610 and 620. In addition, the relationship between the length of the resin 400 applied to the side portions 511 and 512 of the mounting structure 510 and the reliability of the solder joint was also simulated. In the simulation, the size of each part of the 3D mounting structure 500 was set to be the same as in Example 2, except for the length of the resin 400 that was changed. In the simulation, the length of the resin 400 applied was increased from the center of the long sides 10 and 20 of the printed circuit board 300 toward both ends of sides 10 and 20, and the change in stress applied to the solder joints 610 and 620 and the reliability of the solder joint were confirmed.

[0117] Figure 11A is a graph showing the results of a simulation of the relationship between the length of the resin 400 applied to the sides 511 and 512 of the mounting structure 510 in the three-dimensional mounting structure 500 and the stress applied to the solder joints 610 and 620.

[0118] By applying resin 400 to form the reinforcing resin portion 410, thermal deformation of the interposer 220 and the printed circuit board 300 is suppressed. As a result, the stress on the solder joints 610 and 620 is reduced. However, if the length of resin 400 is further increased so that it is longer than the lengths of sides 1 and 2 of the interposer 220, the interposer 220 becomes more susceptible to the effects of thermal deformation of the printed circuit board 300. As a result, the stress on the solder joints 610 and 620 gradually increases, as shown to the right of boundary 11 in Figure 11A. Here, boundary 11 is the point where the length of the applied resin 400 is equal to the lengths of sides 1 and 2 of the interposer 220.

[0119] Figure 11B is a graph showing the results of a simulation regarding the relationship between the length of the resin 400 applied to the sides 511 and 512 of the mounting structure 510 in the three-dimensional mounting structure 500 and the reliability of the solder joint.

[0120] If the resin 400 is applied to a length beyond the boundary 11, the stress on the solder joints 610 and 620 increases as shown in Figure 11A, and consequently, the reliability of the solder joints in the three-dimensional mounting structure 500 decreases as shown in Figure 11B. Therefore, as shown in Figures 11A and 11B, it is preferable to set the length of the resin 400 constituting the reinforcing resin part 410 to an optimal length P within the range that does not exceed the boundary 11. In the three-dimensional mounting structure in which the above simulation was performed, the optimal length P was approximately 15 mm, and one solder joint 620 at each end was exposed from the resin 400.

[0121] (Example 3) Example 3, which corresponds to the second and sixth embodiment, will be described. The dimensions of each part of the 3D mounting structure 500 were as follows: The interposer 220 had sides 1 and 2 each measuring 16.40 mm, and sides 3 and 4 each measuring 15.20 mm. The thickness of the interposer 220, including solder resists 251 and 252, was approximately 0.50 mm, and the thickness of solder resists 251 and 252 was approximately 0.015 mm each. The semiconductor element 210 was mounted on the main surface 231 of the insulating substrate 230. The printed circuit board 300 had sides 10 and 20 each measuring 21.45 mm, and sides 30 and 40 each measuring 15.40 mm. The thickness of the printed circuit board 300, including solder resists 351 and 352, was approximately 0.37 mm, and the thickness of solder resists 351 and 352 was approximately 0.016 mm each.

[0122] The solder joints 610 were arranged in a staggered pattern with a pitch of 0.40 mm. The solder joints 620 were also arranged in a staggered pattern with a pitch of 0.42 mm, surrounding the outer circumference of the semiconductor element 210. The distance between the center of solder joint 610a and the end of the interposer 220 was 0.53 mm. The distance between the center of solder joint 620a and the end of the interposer 220 was 0.40 mm. The solder joints 610 each had a diameter of 0.30 mm. The solder joints 620 each had a diameter of 0.26 mm. At this time, the distance between the outermost position of solder joint 610a and the end of the interposer 220 was 0.40 mm, which was equal to the distance between the center of solder joint 620a and the end of the interposer 220. With the solder joints 610 and 620 formed, the height from the main surface 131 of the printed circuit board 100 to the main surface 332 of the printed circuit board 300 was approximately 0.90 mm.

[0123] In the above-described three-dimensional mounting structure 500, resin 400 was applied to sides 1 and 2 of the interposer 220 and sides 10 and 20 of the printed circuit board 300. When applying the resin 400, the resin 400 was dispensed from a nozzle attached to a dispenser (not shown) while it was being moved.

[0124] Next, the three-dimensional mounting structure 500 coated with resin was placed in an oven (not shown) and heated to cure the resin 400, forming a reinforcing resin part 410 made of the cured resin 400. The curing conditions in the oven were a temperature of 125°C and a time of 30 minutes.

[0125] The reinforcing resin part 410 thus formed had a length of approximately 15.00 mm, a width of approximately 1.60 mm, and a height of approximately 1.20 mm.

[0126] [Other embodiments] The embodiments and examples described above are merely illustrative of some ways to which the present invention may be applied. In other words, the present invention is not limited to the embodiments and examples described above, and can be modified or altered as appropriate without departing from the spirit of the invention.

[0127] In the above-described embodiment, a case was explained in which a plurality of lands 342 are provided on the main surface 332 of the insulating substrate 330 of the printed circuit board 300. However, a plurality of lands may also be provided on the main surface 331 of the insulating substrate 330. In this case, a printed circuit board, semiconductor device, electronic components, etc., may be further mounted on the printed circuit board 300 via solder joints that join the plurality of lands provided on the main surface 331.

[0128] A 3D mounting structure 500 according to another embodiment, in which a printed circuit board and the like are mounted on top of the printed circuit board 300, will be described with reference to Figures 12A to 12C. Figure 12A is a top view showing the 3D mounting structure 500 according to the other embodiment. Figure 12B is a side view of the 3D mounting structure 500 according to the other embodiment as seen from the y-axis direction. Figure 12C is a cross-sectional view of the 3D mounting structure 500 according to the other embodiment as seen from the x-axis direction. Components similar to those in the first to sixth embodiments are denoted by the same reference numerals, and detailed descriptions are omitted or simplified. As shown in Figures 12A to 12C, in this embodiment, for example, a plurality of printed circuit boards 450 and a plurality of electronic components 460 are mounted on the main surface 331 of the insulating substrate 330 of the printed circuit board 300.

[0129] The main surface 331 of the insulating substrate 330 in the printed circuit board 300 has a plurality of lands 341 and a plurality of lands 343 arranged thereon. The lands 341 and 343 are terminals formed of a conductive metallic material, such as copper or gold. Solder resist 351 is provided on the main surface 331 of the insulating substrate 330. Each of the plurality of lands 341 and each of the plurality of lands 343 is exposed by an opening formed in the solder resist 351. The lands 341 and 343 may be either SMD or NSMD lands.

[0130] Multiple printed circuit boards 450 are mounting substrates for semiconductor elements 461 in semiconductor devices such as memory, and semiconductor devices are constructed by mounting (die bonding) semiconductor elements 461 and other components on the printed circuit boards 450. The printed circuit boards 450 have an insulating substrate 430. Multiple lands 442 are arranged on the main surface 432 of the insulating substrate 430. Solder resist 452 is also provided on the main surface 432 of the insulating substrate 430. Multiple lands 442 are exposed by openings formed in the solder resist 452. Multiple electronic components 460 are chip components such as capacitors and resistors.

[0131] On the main surface 431 of the insulating substrate 430, opposite to the main surface 432, a semiconductor element 461, such as a memory, is mounted on a printed circuit board 450. A sealing resin 462 is formed on the main surface 431 containing the semiconductor element 461, thereby sealing the semiconductor element 461. The semiconductor device includes at least the semiconductor element 461, and optionally further includes a printed circuit board 450 and the sealing resin 462.

[0132] Multiple lands 341 on the printed circuit board 300 and multiple lands 442 on the printed circuit board 450 are joined by solder joints 630. In this way, the multiple printed circuit boards 450 are positioned on the side opposite to the interposer 220 relative to the printed circuit board 300 and are joined to the printed circuit board 300 via the multiple solder joints 630. In addition, multiple lands 343 on the printed circuit board 300 and the electronic component 460 are joined by solder joints 640. The solder forming the solder joints 630 and 640 is, for example, solder balls.

[0133] Thus, a semiconductor device including a semiconductor element 461, a printed circuit board 450, and a sealing resin 462 is arranged on the side of the printed circuit board 300 opposite to the side of the interposer 220. For example, a first semiconductor device including one printed circuit board 450 and at least one semiconductor element 461, and a second semiconductor device including another printed circuit board 450 and at least one semiconductor element 461 are arranged side by side in the x-axis direction. Therefore, it is preferable that the x-axis direction in which the multiple semiconductor devices are arranged is the direction of the long side of the printed circuit board 300. In the printed circuit board 300 as well, it is effective to provide the reinforcing resin portion 410 on the long side rather than the short side. Therefore, it is preferable to arrange the reinforcing resin portion 410 on the side 511 and side 512 along the x-axis direction in which the multiple semiconductor devices are arranged. This allows the distortion of the printed circuit board 300 caused by each of the multiple semiconductor devices to be suppressed by the reinforcing resin portion 410 on the side 511 and side 512. Furthermore, in addition to the sides 511 and 512, reinforcing resin parts 410 may also be placed on the sides 513 and 514, as shown in Figures 4C and 9A. Note that when multiple semiconductor devices are arranged in the x-axis direction, reinforcing resin parts 410 can also be provided only on the sides 513 and 514 along the y-axis direction, but the reinforcing effect will be reduced compared to the configuration shown in Figure 12A.

[0134] As described above, multiple printed circuit boards 450 and multiple electronic components 460 may be mounted on the printed circuit board 300. In this embodiment as well, a configuration including a reinforcing resin portion 410 attached to the printed circuit board 100, interposer 220 and printed circuit board 300 can be adopted, similar to the first to sixth embodiments described above. In this case, the reinforcing resin portion 410 is separated from the solder joints 630, 640 and the multiple printed circuit boards 450.

[0135] This embodiment includes the following configuration. (Composition 1) First printed circuit board and A second printed circuit board is placed on the main surface of the first printed circuit board and is joined to the first printed circuit board via a plurality of first solder joints, A third printed circuit board is positioned on the opposite side of the second printed circuit board from the first printed circuit board and is joined to the second printed circuit board via a plurality of second solder joints, First reinforcing resin part, It has a second reinforcing resin part, The second printed circuit board has a first side surface and a second side surface that face each other in a first direction, and a third side surface and a fourth side surface that face each other in a second direction that intersects the first direction. The first reinforcing resin portion is attached to the main surface of the first printed circuit board, the first side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the two ends of the first side surface of the second printed circuit board in the second direction. The second reinforcing resin portion is attached to the main surface of the first printed circuit board, the second side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second side surface of the second printed circuit board in the second direction. A module characterized by the following features. (Configuration 2) One end of the first side is closer to the third side than the fourth side, and one end of the second side is closer to the fourth side than the third side. The module according to configuration 1, characterized by the above. (Composition 3) The first reinforcing resin portion is separated from the other end of the second end of the first side surface of the second printed circuit board in the second direction, The second reinforcing resin portion is separated from the other end of the second side surface of the second printed circuit board in the second direction. A module according to configuration 1 or 2, characterized by the above. (Composition 4) The first reinforcing resin portion is located away from the solder joint among the plurality of second solder joints that is closest to one end of the first side surface. The second reinforcing resin portion is located away from the solder joint that is closest to one end of the second side surface among the plurality of second solder joints. A module according to any one of configurations 1 to 3, characterized by the above. (Composition 5) The first reinforcing resin portion is located away from the solder joint that is closest to the other end of the first side surface among the plurality of second solder joints. The second reinforcing resin portion is located away from the solder joint that is closest to the other end of the second side surface among the plurality of second solder joints. The module according to configuration 4, characterized by the features described above. (Composition 6) The distance between the solder joint closest to one end of the first side surface and the solder joint closest to the other end of the first side surface is The distance between the solder joint closest to one end of the first side surface and the solder joint closest to the other end of the first side surface is greater than the distance between the solder joints closest to one end of the first side surface. The module according to configuration 5, characterized by the features described above. (Composition 7) The first reinforcing resin portion is located away from the solder joint that is closest to the first reinforcing resin portion among the plurality of second solder joints. The second reinforcing resin portion is located away from the solder joint that is closest to the second reinforcing resin portion among the plurality of second solder joints. A module according to configuration 1 or 2, characterized by the above. (Claim 8) The first reinforcing resin portion is attached to the solder joint that is closest to the first reinforcing resin portion among the plurality of second solder joints. The second reinforcing resin portion is attached to the solder joint that is closest to the second reinforcing resin portion among the plurality of second solder joints. A module according to any one of configurations 1 to 7, characterized by the above. (Composition 9) The resin portion made of the same material as the first reinforcing resin portion is not attached to the third side surface. A resin part made of the same material as the second reinforcing resin part is not attached to the fourth side surface. A module according to any one of configurations 1 to 8, characterized in that it is a module according to any one of these configurations. (Composition 10) Third reinforcing resin part, It has a fourth reinforcing resin part, The third reinforcing resin portion is attached to the main surface of the first printed circuit board, the third side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second direction of the third side surface of the second printed circuit board. The fourth reinforcing resin portion is attached to the main surface of the first printed circuit board, the fourth side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second direction of the fourth side surface of the second printed circuit board. A module according to any one of configurations 1 to 9, characterized by the above. (Composition 11) First printed circuit board and A second printed circuit board is placed on the main surface of the first printed circuit board and is joined to the first printed circuit board via a plurality of first solder joints, A third printed circuit board is positioned on the opposite side of the second printed circuit board from the first printed circuit board and is joined to the second printed circuit board via a plurality of second solder joints, First reinforcing resin part, It has a second reinforcing resin part, The second printed circuit board has a first side surface and a second side surface that face each other in a first direction, and a third side surface and a fourth side surface that face each other in a second direction that intersects the first direction. The first reinforcing resin portion is attached to the main surface of the first printed circuit board, the first side surface of the second printed circuit board, and the third printed circuit board, and is located away from the solder joint closest to the first reinforcing resin portion among the plurality of first solder joints and the plurality of second solder joints, and is attached to the solder joint closest to the first reinforcing resin portion among the other solder joints of the plurality of first solder joints and the plurality of second solder joints. A module characterized by the following features. (Composition 12) The second reinforcing resin portion is attached to the main surface of the first printed circuit board, the second side surface of the second printed circuit board, and the third printed circuit board, and is located away from the solder joint closest to the second reinforcing resin portion among the plurality of first solder joints and the plurality of second solder joints, and is attached to the solder joint closest to the second reinforcing resin portion among the other of the plurality of first solder joints and the plurality of second solder joints. A module according to configuration 11, characterized by the features described above. (Composition 13) The aforementioned joint is the plurality of first solder joints, The other joint is the plurality of second solder joints. A module according to configuration 11 or 12, characterized by the above. (Composition 14) The distance between the solder joint closest to the first reinforcing resin portion of one of the joints and the first side surface is longer than the distance between the solder joint closest to the first reinforcing resin portion of the other joint and the first side surface. A module according to configuration 13, characterized by the above. (Composition 15) Between the first printed circuit board and the second printed circuit board, there is a solder joint that is not joined to either the first printed circuit board or the second printed circuit board. The first reinforcing resin part is attached to the solder part. A module according to any one of configurations 1 to 14, characterized by the above. (Composition 16) The second printed circuit board has a step formed on the outside of the second solder joint, The first reinforcing resin portion is formed on the aforementioned step. A module according to any one of configurations 1 to 15, characterized by the features described herein. (Composition 17) The second printed circuit board comprises a substrate and a solder resist formed on the substrate, The aforementioned step is formed in the substrate The module according to configuration 16, characterized by the above. (Composition 18) The second printed circuit board comprises a substrate and a solder resist formed on the substrate, The aforementioned step is an opening formed in the solder resist. The module according to configuration 16, characterized by the above. (Composition 19) The first reinforcing resin portion faces the plurality of third solder joints among the plurality of first solder parts and the plurality of fourth solder joints among the plurality of second solder joints. A module according to any one of configurations 1 to 18, characterized by the above. (Composition 20) The first reinforcing resin portion and the second reinforcing resin portion have a portion located between the first printed circuit board and the second printed circuit board and a portion located between the second printed circuit board and the third printed circuit board in a third direction perpendicular to the main surface of the first printed circuit board. A module according to any one of configurations 1 to 19, characterized by the features described herein. (Composition 21) It has a semiconductor element disposed between the second printed circuit board and the third printed circuit board, The plurality of second solder joints are arranged around the semiconductor element. In the first direction, the semiconductor element is provided between the first reinforcing resin portion and the second reinforcing resin portion. A module according to any one of configurations 1 to 20, characterized in that it is a module according to any one of these configurations. (Composition 22) In the second direction, the second reinforcing resin portion is longer than the semiconductor element. The module according to configuration 21, characterized by the above. (Composition 23) The sum of the number of second solder joints located between the semiconductor element and the first side surface in the first direction and the number of second solder joints located between the semiconductor element and the second side surface in the first direction is The number of second solder joints located between the semiconductor element and the third side surface in the second direction is less than the sum of the number of second solder joints located between the semiconductor element and the fourth side surface in the second direction. The module according to configuration 21, characterized by the above. (Composition 24) The thickness of the third printed circuit board is smaller than the thickness of the second printed circuit board. A module according to any one of configurations 1 to 23, characterized by the above. (Composition 25) The third printed circuit board has a fifth and sixth side surface that face each other in the first direction, and a seventh and eighth side surface that face each other in the second direction. The first reinforcing resin portion is attached to the fifth side surface of the third printed circuit board. The second reinforcing resin portion is attached to the sixth side surface of the third printed circuit board. A module according to any one of configurations 1 to 24, characterized by the features described herein. (Composition 26) The first and second sides of the second printed circuit board are located between the first printed circuit board and the third printed circuit board in a third direction perpendicular to the main surface of the first printed circuit board. A module according to any one of configurations 1 to 25, characterized by the features described herein. (Composition 27) The third printed circuit board is positioned on the opposite side from the second printed circuit board, and has a fourth printed circuit board that is joined to the third printed circuit board via a plurality of third solder joints. The first reinforcing resin portion and the second reinforcing resin portion are separated from the third solder joint and the fourth printed circuit board. A module according to any one of configurations 1, 2, 11, and 12, characterized by the features described herein. (Composition 28) The distance between the seventh side and the eighth side is greater than the distance between the fifth side and the sixth side. The distance between the seventh and eighth side surfaces is greater than the distance between the third and fourth side surfaces. The module according to configuration 25, characterized by the features described above. (Composition 29) A first semiconductor device is positioned on the side of the third printed circuit board opposite to the side of the second printed circuit board, The semiconductor device comprises a second semiconductor device located on the side of the third printed circuit board opposite to the side of the second printed circuit board, The first semiconductor device and the second semiconductor device are arranged side by side in the second direction. A module according to any one of configurations 1 to 28, characterized by the above. (Composition 30) The casing and The first module is located inside the aforementioned housing, A second module is located inside the aforementioned housing, Equipped with, The first module and the second module are electrically connected, The second module is the module described in any one of items 1 to 29. An electronic device characterized by the following features. (Composition 31) The first module and the second module are electrically connected via flexible wiring. The electronic device according to configuration 30, characterized by the above. (Composition 32) The first module includes an image sensor. The electronic device according to configuration 30, characterized by the above. [Explanation of Symbols]

[0136] 100…Printed circuit board 200... Semiconductor equipment 210... Semiconductor elements 220... Interposer 300…Printed circuit board 400... Resin 410…Reinforcement resin part 500...3D implementation structure 510...Implementation structure 610... Solder joint 620... Solder joint 710... Solder joint 720... Solder joint 255…Opening 260... step 650... Dummy bump

Claims

1. First printed circuit board and A second printed circuit board is placed on the main surface of the first printed circuit board and joined to the first printed circuit board via a plurality of first solder joints, A third printed circuit board is positioned on the opposite side of the second printed circuit board from the first printed circuit board and is joined to the second printed circuit board via a plurality of second solder joints. First reinforcing resin part, It has a second reinforcing resin part, The second printed circuit board has first and second sides facing each other in a first direction, and third and fourth sides facing each other in a second direction intersecting the first direction. The first reinforcing resin portion is attached to the main surface of the first printed circuit board, the first side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the two ends of the first side surface of the second printed circuit board in the second direction. The second reinforcing resin portion is attached to the main surface of the first printed circuit board, the second side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second side surface of the second printed circuit board in the second direction. A module characterized by the following features.

2. One end of the first side is closer to the third side than the fourth side, and one end of the second side is closer to the fourth side than the third side. The module according to feature 1.

3. The first reinforcing resin portion is separated from the other end of the second end of the first side surface of the second printed circuit board in the second direction, The second reinforcing resin portion is separated from the other end of the second side surface of the second printed circuit board in the second direction. The module according to feature 1 or 2.

4. The first reinforcing resin portion is located away from the solder joint that is closest to one end of the first side surface among the plurality of second solder joints. The second reinforcing resin portion is separated from the solder joint that is closest to one end of the second side surface among the plurality of second solder joints. The module according to feature 1 or 2.

5. The first reinforcing resin portion is located away from the solder joint that is closest to the other end of the first side surface among the plurality of second solder joints. The second reinforcing resin portion is separated from the solder joint that is closest to the other end of the second side surface among the plurality of second solder joints. The module according to feature 4.

6. The distance between the solder joint closest to one end of the first side surface and the solder joint closest to the other end of the first side surface is The distance between the solder joint closest to one end of the first side surface and the solder joint closest to the other end of the first side surface is greater than the distance between the solder joints closest to one end of the first side surface. The module according to feature 5.

7. The first reinforcing resin portion is located away from the solder joint that is closest to the first reinforcing resin portion among the plurality of second solder joints. The second reinforcing resin portion is located away from the solder joint that is closest to the second reinforcing resin portion among the plurality of second solder joints. The module according to feature 1 or 2.

8. The first reinforcing resin portion is attached to the solder joint that is closest to the first reinforcing resin portion among the plurality of second solder joints. The second reinforcing resin portion is attached to the solder joint that is closest to the second reinforcing resin portion among the plurality of second solder joints. The module according to feature 1 or 2.

9. The resin portion made of the same material as the first reinforcing resin portion is not attached to the third side surface. A resin part made of the same material as the second reinforcing resin part is not attached to the fourth side surface. The module according to feature 1 or 2.

10. Third reinforcing resin part, It has a fourth reinforcing resin part, The third reinforcing resin portion is attached to the main surface of the first printed circuit board, the third side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second direction of the third side surface of the second printed circuit board. The fourth reinforcing resin portion is attached to the main surface of the first printed circuit board, the fourth side surface of the second printed circuit board, and the third printed circuit board, and is separated from at least one end of the second direction of the fourth side surface of the second printed circuit board. The module according to feature 1 or 2.

11. First printed circuit board and A second printed circuit board is placed on the main surface of the first printed circuit board and joined to the first printed circuit board via a plurality of first solder joints, A third printed circuit board is positioned on the opposite side of the second printed circuit board from the first printed circuit board and is joined to the second printed circuit board via a plurality of second solder joints. First reinforcing resin part, It has a second reinforcing resin part, The second printed circuit board has first and second sides facing each other in a first direction, and third and fourth sides facing each other in a second direction intersecting the first direction. The first reinforcing resin portion is attached to the main surface of the first printed circuit board, the first side surface of the second printed circuit board, and the third printed circuit board, and is located away from the solder joint closest to the first reinforcing resin portion among the plurality of first solder joints and the plurality of second solder joints, and is attached to the solder joint closest to the first reinforcing resin portion among the other solder joints of the plurality of first solder joints and the plurality of second solder joints. A module characterized by the following features.

12. The second reinforcing resin portion is attached to the main surface of the first printed circuit board, the second side surface of the second printed circuit board, and the third printed circuit board, and is located away from the solder joint closest to the second reinforcing resin portion among the plurality of first solder joints and the plurality of second solder joints, and is attached to the solder joint closest to the second reinforcing resin portion among the other solder joints of the plurality of first solder joints and the plurality of second solder joints. The module according to feature 11.

13. The aforementioned one joint is the plurality of first solder joints, The other joint is the plurality of second solder joints. The module according to claim 11 or 12.

14. The distance between the solder joint closest to the first reinforcing resin portion of one of the joints and the first side surface is longer than the distance between the solder joint closest to the first reinforcing resin portion of the other joint and the first side surface. The module according to feature 13.

15. Between the first printed circuit board and the second printed circuit board, there is a solder joint that is not joined to either the first printed circuit board or the second printed circuit board. The first reinforcing resin part is attached to the solder part. The module according to any one of claims 1, 2, 11, and 12.

16. The second printed circuit board has a step formed on the outside of the second solder joint, The first reinforcing resin portion is formed on the aforementioned step. The module according to any one of claims 1, 2, 11, and 12.

17. The second printed circuit board comprises a substrate and a solder resist formed on the substrate. The aforementioned step is formed in the substrate The module according to feature 16.

18. The second printed circuit board comprises a substrate and a solder resist formed on the substrate. The aforementioned step is an opening formed in the solder resist. The module according to feature 16.

19. The first reinforcing resin portion faces the plurality of third solder joints among the plurality of first solder joints and the plurality of fourth solder joints among the plurality of second solder joints. The module according to any one of claims 1, 2, 11, and 12.

20. The first reinforcing resin portion and the second reinforcing resin portion have a portion located between the first printed circuit board and the second printed circuit board and a portion located between the second printed circuit board and the third printed circuit board in a third direction perpendicular to the main surface of the first printed circuit board. The module according to any one of claims 1, 2, 11, and 12.

21. It has a semiconductor element disposed between the second printed circuit board and the third printed circuit board, The plurality of second solder joints are arranged around the semiconductor element. In the first direction, the semiconductor element is provided between the first reinforcing resin portion and the second reinforcing resin portion. The module according to any one of claims 1, 2, 11, and 12.

22. In the second direction, the second reinforcing resin portion is longer than the semiconductor element. The module according to feature 21.

23. The sum of the number of second solder joints located between the semiconductor element and the first side surface in the first direction and the number of second solder joints located between the semiconductor element and the second side surface in the first direction is The number of second solder joints located between the semiconductor element and the third side surface in the second direction is less than the sum of the number of second solder joints located between the semiconductor element and the fourth side surface in the second direction. The module according to feature 21.

24. The thickness of the third printed circuit board is smaller than the thickness of the second printed circuit board. The module according to any one of claims 1, 2, 11, and 12.

25. The third printed circuit board has a fifth side and a sixth side facing each other in the first direction, and a seventh side and an eighth side facing each other in the second direction, The first reinforcing resin portion is attached to the fifth side surface of the third printed circuit board. The second reinforcing resin portion is attached to the sixth side surface of the third printed circuit board. The module according to any one of claims 1, 2, 11, and 12.

26. The first and second sides of the second printed circuit board are located between the first printed circuit board and the third printed circuit board in a third direction perpendicular to the main surface of the first printed circuit board. The module according to any one of claims 1, 2, 11, and 12.

27. The third printed circuit board is positioned on the opposite side from the second printed circuit board, and has a fourth printed circuit board that is joined to the third printed circuit board via a plurality of third solder joints. The first reinforcing resin portion and the second reinforcing resin portion are separated from the third solder joint and the fourth printed circuit board. The module according to any one of claims 1, 2, 11, and 12.

28. The distance between the seventh side and the eighth side is greater than the distance between the fifth side and the sixth side. The distance between the seventh side and the eighth side is greater than the distance between the third side and the fourth side. The module according to feature 25.

29. A first semiconductor device is positioned on the side of the third printed circuit board opposite to the side of the second printed circuit board, The semiconductor device comprises a second semiconductor device positioned on the side of the third printed circuit board opposite to the side of the second printed circuit board, The first semiconductor device and the second semiconductor device are arranged side by side in the second direction. The module according to any one of claims 1, 2, 11, and 12.

30. The casing and The first module is located inside the aforementioned housing, A second module is located inside the aforementioned housing, Equipped with, The first module and the second module are electrically connected, The second module is the module according to any one of claims 1, 2, 11, and 12. An electronic device characterized by the following features.

31. The first module and the second module are electrically connected via flexible wiring. The electronic device according to claim 30.

32. The first module includes an image sensor. The electronic device according to claim 30.

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