Module

Abstract

This module comprises: a substrate (1) having a main surface (1a); a semiconductor component (3) mounted on the main surface (1a); and a sealing resin layer (6) formed of a sealing resin so as to seal the main surface (1a) and a side surface of the semiconductor component (3). The semiconductor component (3) comprises a component body (31) and a bump (32) connected to the substrate (1) side surface of the component body (31). The mounting of the semiconductor component (3) to the main surface (1a) is performed by connecting the bump (32) to the main surface (1a) in a state in which the component body (31) is separated from the main surface (1a). A gap between the component body (31) and the main surface (1a) is filled with an underfill resin, thereby forming an underfill layer (7). The elastic coefficient of the underfill resin is lower than the elastic coefficient of the sealing resin. The underfill layer (7) includes a protruding portion (7e) protruding outside a region in which the component body (31) is projected onto the main surface (1a). The protruding portion (7e) is covered by the sealing resin layer (6). A groove (8) is formed in the sealing resin layer (6) in a region in which the protruding portion (7e) is projected onto a surface of the sealing resin layer (6) on the far side from the substrate (1).

Description

Module

[0001] The present invention relates to a module.

[0002] In order to address the problem of damage to the joint between the component-embedded substrate and the motherboard under temperature cycle conditions in a high-frequency module, a configuration in which a groove is formed between the semiconductor component and the external connection terminal is described in JP 2021-197568 A (Patent Document 1).

[0003] In a molded package in which package components are mounted on a substrate and sealed with resin, a configuration is described in JP 2015-2245 A (Patent Document 2) in which a groove is formed from the top surface of the resin to the bottom surface in order to prevent stress caused by thermal expansion and thermal contraction from being applied to the package components.

[0004] International Publication WO 2018 / 194012 A1 (Patent Document 3) describes a module having a structure in which multiple components are mounted on the main surface of a substrate and sealed with an encapsulating resin layer, with a recess formed from the upper surface of the encapsulating resin layer toward the main surface of the substrate. The surface of the encapsulating resin layer other than the interior of the recess is covered with a shielding layer. This document states that unwanted electromagnetic waves emitted by the components are effectively directed out of the module through the recess formed in the encapsulating resin layer, making it difficult for the waves to reach other components.

[0005] JP 2021-197568 A JP 2015-2245 A International Publication WO2018 / 194012A1

[0006] In the configurations disclosed in Patent Documents 1 to 3, a groove is formed in the sealing resin portion near the side of the mounted component for the purpose of stress relief or prevention of electromagnetic interference.

[0007] However, the effect of bending stress is significantly affected by the difference in the linear expansion coefficient between the sealing resin below the mounted component and the substrate. When the mounted component is large, simply providing a groove near the side of the component is not enough to deal with the stress.

[0008] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a module that can alleviate bending stress even when the size of the semiconductor components mounted on the substrate is large.

[0009] To achieve the above object, a module according to the present invention comprises a substrate having a main surface, a semiconductor component mounted on the main surface, and an encapsulating resin layer formed of encapsulating resin so as to encapsulate the main surface and side surfaces of the semiconductor component. The semiconductor component comprises a component body and bumps connected to the surface of the component body facing the substrate. The semiconductor component is mounted on the main surface by connecting the bumps to the main surface while the component body is spaced from the main surface. An underfill layer is formed by filling the gap between the component body and the main surface with underfill resin. The elastic modulus of the underfill resin is lower than that of the encapsulating resin. The underfill layer includes a protruding portion that exists outside the area where the component body is projected onto the main surface. The protruding portion is covered by the encapsulating resin layer. A groove is formed in the encapsulating resin layer within the area where the protruding portion is projected onto the surface of the encapsulating resin layer farther from the substrate.

[0010] According to the present invention, the stress caused by the difference in linear expansion coefficient between the semiconductor component and the substrate is alleviated by the underfill layer, and further, the stress caused by the difference in linear expansion coefficient between the sealing resin layer and the semiconductor component is alleviated by the groove, so that even if the size of the semiconductor component mounted on the substrate is large, the stress caused by bending can be alleviated.

[0011] FIG. 1 is a cross-sectional view of a module in a first embodiment according to the present invention. FIG. 2 is an enlarged view of a Z1 portion in FIG. 1 . FIG. 3 is a plan view of a module in a first embodiment according to the present invention. FIG. 4 is an enlarged view of a bottom of a groove and its vicinity in a module in a first modified example of the module in a first embodiment according to the present invention. FIG. 5 is an enlarged view of a bottom of a groove and its vicinity in a second modified example of the module in a first embodiment according to the present invention. FIG. 6 is a plan view of a module in a second embodiment according to the present invention. FIG. 7 is a plan view of a module in a third embodiment according to the present invention. FIG. 8 is a plan view of a first modified example of the module in a third embodiment according to the present invention. FIG. 9 is a plan view of a second modified example of the module in a third embodiment according to the present invention. FIG. 10 is a plan view of a third modified example of the module in a third embodiment according to the present invention. FIG. 11 is a plan view of a fourth modified example of the module in a third embodiment according to the present invention.

[0012] The dimensional ratios shown in the drawings do not necessarily represent the actual ratios, and may be exaggerated for the sake of convenience. In the following description, when the concepts of up and down are mentioned, they do not necessarily mean absolute up and down, but may mean relative up and down in the illustrated position.

[0013] 1 to 3, a module according to a first embodiment of the present invention will be described. A cross-sectional view of the module according to the present embodiment is shown in Fig. 1. An enlarged view of part Z1 in Fig. 1 is shown in Fig. 2.

[0014] The module 101 in this embodiment includes a substrate 1 having a main surface 1a, a semiconductor component 3 mounted on the main surface 1a, and an encapsulating resin layer 6 formed of encapsulating resin so as to encapsulate the main surface 1a and the side surfaces of the semiconductor component 3. The semiconductor component 3 may be, for example, an IC (Integrated Circuit). The top surface of the semiconductor component 3 may be exposed from the encapsulating resin layer 6. A shielding film may be provided so as to cover the top surface and side surfaces of the encapsulating resin layer 6. The shielding film is a metal film. The top surface of the semiconductor component 3 may also be covered with the shielding film. Note that this embodiment shows an example in which there is no shielding film.

[0015] In addition to the semiconductor component 3, components 41, 42, 43, and 44 are mounted on the main surface 1a of the substrate 1.

[0016] The semiconductor component 3 includes a component body 31 and bumps 32 connected to the surface of the component body 31 facing the substrate 1. The semiconductor component 3 is mounted on the main surface 1a by connecting the bumps 32 to the main surface 1a while the component body 31 is spaced from the main surface 1a. An underfill resin is filled in the gap between the component body 31 and the main surface 1a to form an underfill layer 7. The elastic modulus of the underfill resin is lower than that of the encapsulating resin. The underfill layer 7 includes a protruding portion 7e that protrudes outside the area where the component body 31 is projected onto the main surface 1a. The protruding portion 7e is covered by the encapsulating resin layer 6. A groove 8 is formed in the encapsulating resin layer 6 within the area where the protruding portion 7e is projected onto the surface of the encapsulating resin layer 6 farther from the substrate 1.

[0017] FIG. 2 shows an enlarged view of the bottom of the groove 8 in FIG. 1 . FIG. 3 shows a plan view of the module 101 according to this embodiment. As shown in FIG. 2 , the groove 8 penetrates the protruding portion 7e of the underfill layer 7 but does not reach the main surface 1a. The bottom of the groove 8 is U-shaped when viewed in cross section. The bottom of the groove 8 is located within the underfill layer 7. In the example shown here, the underfill layer 7 includes a portion 7c and a protruding portion 7e. The portion 7c is the portion of the underfill layer 7 that is located in the region where the component body 31 is projected onto the main surface 1a. The protruding portion 7e is the portion of the underfill layer 7 that protrudes outward from the portion 7c. In the example shown here, the protruding portion 7e extends continuously from the portion 7c, but when viewed in cross section, the protruding portion 7e may not be completely continuous with the portion 7c. When viewed in cross section, the underfill layer 7 may be interrupted midway from the portion 7c to the tip of the protruding portion 7e.

[0018] 3, when viewed from a direction perpendicular to the main surface 1a, the grooves 8 are formed so as to be spaced apart from the semiconductor component 3 and to follow the sides of the semiconductor component 3. In the example shown here, the module 101 has a rectangular shape, and the semiconductor component 3 is arranged in the middle part in the longitudinal direction so as to occupy most of the width of the module 101.

[0019] In this embodiment, stress caused by the difference in linear expansion coefficient between the semiconductor component 3 and the substrate 1 is alleviated by the underfill layer 7. Furthermore, stress caused by the difference in linear expansion coefficient between the encapsulating resin layer 6 and the semiconductor component 3 is alleviated by the groove 8. Furthermore, by configuring the bottom of the groove 8 to be within the underfill layer 7, fracture resistance is improved. Therefore, in this embodiment, a module that can alleviate bending stress can be realized even when the size of the semiconductor component mounted on the substrate is large.

[0020] The shape of the bottom of the groove 8 when viewed in cross section may be U-shaped as shown in Fig. 4, but may also be other shapes. For example, it may be rectangular as shown in Fig. 5, or V-shaped as shown in Fig. 6.

[0021] In this embodiment, it is preferable that the bottom of the groove 8 penetrates into the protruding portion 7e but does not reach the main surface 1a. Even if the bottom of the groove 8 is deep enough not to reach the protruding portion 7e, it is still effective. However, as shown in this embodiment, it is preferable that the bottom of the groove 8 penetrates into the protruding portion 7e, because this can block the transmission of stress within the sealing resin layer 6 at this position.

[0022] As shown in this embodiment, when viewed from a direction perpendicular to the main surface 1a, the grooves 8 are preferably formed so as to be spaced apart from the semiconductor component 3 and to follow the sides of the semiconductor component 3. By employing this configuration, stress caused by the difference in the linear expansion coefficient between the encapsulating resin layer 6 and the semiconductor component 3 can be efficiently blocked.

[0023] It is preferable that the encapsulating resin and the underfill resin have different filler content conditions. By adopting this configuration, it is possible to easily achieve a difference in the elastic modulus between the two. If each resin is a combination of a main material and a filler, the main material of the encapsulating resin and the main material of the underfill resin may be the same. For example, both the underfill resin and the encapsulating resin may be primarily made of epoxy resin. The filler content conditions are a concept that includes the filler content, average filler diameter, filler shape, filler material, etc. Even if the main material conditions are the same, the elastic modulus can be changed by changing the filler content conditions. By changing the filler content conditions, it is also possible to adjust the resin to have a desired elastic modulus.

[0024] (Embodiment 2) A module according to embodiment 2 of the present invention will be described with reference to FIG. 7 . FIG. 7 shows a plan view of a module according to this embodiment. Module 102 has grooves 8i instead of the grooves 8 described in embodiment 1. When viewed in plan, grooves 8i are dotted lines. The grooves may also have dotted lines like this. In FIG. 7 , the shapes of the elements constituting the dotted lines of grooves 8i are shown as squares, but this is merely an example. The shapes of the elements of the dotted lines may be rectangular, polygonal, circular, elliptical, or the like. Furthermore, the dotted lines of grooves 8i do not need to be uniformly repeated in the same shape, and different shapes may be combined and arranged.

[0025] In this embodiment, the grooves are dotted lines when viewed in a plan view, meaning that there are interrupted portions along the grooves. The sealing resin layer 6 is connected at these interrupted portions. As such, the sealing resin layers 6 on both sides of the groove 8 are connected at some points, which increases the strength of the entire module.

[0026] In this embodiment, an example in which the grooves are formed as dotted lines when viewed in a plan view has been shown, but the grooves may be formed as broken lines.

[0027] Third Embodiment A module according to a third embodiment of the present invention will be described with reference to Fig. 8. Fig. 8 shows a plan view of the module according to the present embodiment.

[0028] In this example, the module 103 has a rectangular shape, and the semiconductor component 3 is disposed in a position close to one end of the module 103. The groove 8 is provided along the short side of the semiconductor component 3. The groove 8 is provided so as to divide the sealing resin layer 6. The groove 8 is provided so as to extend from a point midway along one long side of the module 103 to a point midway along the other long side.

[0029] The present embodiment can also achieve the effects described in the first embodiment. Note that a variation of the module of the present embodiment may have a configuration like module 104 shown in FIG. 9. Module 104 has a rectangular shape when viewed in plan view, and semiconductor component 3 is arranged so as to occupy a certain section of the module 104. Grooves 8 are arranged along each of the two short sides of semiconductor component 3. Each of the two grooves 8 is provided so as to extend from one long side of module 104 to the other long side.

[0030] As a further modification of the module of this embodiment, a configuration like module 105 shown in Fig. 10 may be used. Module 105 is rectangular in plan view, and semiconductor component 3 is disposed near one corner of module 105. Groove 8 is provided in an L-shape so as to surround semiconductor component 3 near one corner of module 105.

[0031] As a further modification of the module of this embodiment, a configuration like module 106 shown in Fig. 11 may be used. Module 106 is rectangular in plan view, and semiconductor component 3 is disposed midway along one of the outlines of module 106. Groove 8 is provided so as to surround semiconductor component 3 of module 106 from three sides.

[0032] As a further modification of the module of this embodiment, a configuration like module 107 shown in FIG. 12 may be used. In module 107, semiconductor component 3 is disposed in the middle away from any side. Groove 8 is provided so as to completely surround semiconductor component 3. Groove 8 is provided in an annular shape. As exemplified here, groove 8 is preferably disposed so as to surround semiconductor component 3 when viewed from a direction perpendicular to main surface 1a.

[0033] When viewed from a direction perpendicular to the main surface 1a, the semiconductor component 3 is preferably arranged so that at least one side of the semiconductor component 3 follows the outline of the substrate 1, and the groove 8 is preferably provided so as to be spaced apart from the semiconductor component 3 and to follow one of the sides of the semiconductor component 3 that does not follow the outline of the substrate 1. By adopting this configuration, the semiconductor component 3 can be appropriately positioned using the outline of the substrate 1, while the required length of the groove 8 can be reduced. Furthermore, since the groove can be omitted in the portion where the side of the semiconductor component 3 follows the outline of the substrate, the amount of work required to form the groove can be reduced.

[0034] It should be noted that a plurality of the above-described embodiments may be employed in combination as appropriate. Furthermore, the number of semiconductor components 3 provided in one module is not limited to one. One module may be equipped with a plurality of semiconductor components 3. When one module is equipped with a plurality of semiconductor components 3, a plurality of the above-described embodiments may be selected for each of the semiconductor components 3 and employed in combination as appropriate.

[0035] The above-described embodiments disclosed herein are illustrative in all respects and are not limiting. The scope of the present invention is defined by the claims, and includes all modifications within the meaning and scope of the claims.

[0036] (Note) (Note 1) A module comprising: a substrate having a main surface; a semiconductor component mounted on the main surface; and an encapsulating resin layer formed of encapsulating resin so as to encapsulate the main surface and side surfaces of the semiconductor component; the semiconductor component comprises a component body and bumps connected to a surface of the component body facing the substrate; the semiconductor component is mounted on the main surface by connecting the bumps to the main surface with the component body spaced apart from the main surface; an underfill layer is formed by filling a gap between the component body and the main surface with underfill resin; an elastic modulus of the underfill resin is lower than an elastic modulus of the encapsulating resin; the underfill layer includes a protruding portion that exists outside an area where the component body is projected onto the main surface; the protruding portion is covered by the encapsulating resin layer; and a groove is formed in the encapsulating resin layer within an area where the protruding portion is projected onto a surface of the encapsulating resin layer farther from the substrate.

[0037] (Supplementary Note 2) The module according to Supplementary Note 1, wherein the bottom of the groove extends into the protruding portion but does not reach the main surface.

[0038] (Supplementary Note 3) The module according to Supplementary Note 1 or 2, wherein when viewed from a direction perpendicular to the main surface, the groove is formed so as to be spaced apart from the semiconductor component and to follow a side of the semiconductor component.

[0039] (Supplementary Note 4) The module according to Supplementary Note 3, wherein the groove is arranged to surround the semiconductor component when viewed from a direction perpendicular to the main surface.

[0040] (Supplementary Note 5) The module described in Supplementary Note 1 or 2, wherein, when viewed from a direction perpendicular to the main surface, the semiconductor component is arranged such that at least one side of the semiconductor component follows an outline of the substrate, and the groove is spaced apart from the semiconductor component and follows one of the sides of the semiconductor component that does not follow the outline of the substrate.

[0041] (Supplementary Note 6) The module according to any one of Supplementary Notes 1 to 5, wherein the sealing resin and the underfill resin have different filler content conditions.

[0042] 1 substrate, 1a main surface, 3 semiconductor component, 6 sealing resin layer, 7 underfill layer, 7c portion, 7e protruding portion, 8, 8i groove, 31 component body, 32 bump, 41, 42, 43, 44 component, 101, 102, 103, 104, 105, 106, 107 module.

Claims

1. A module comprising: a substrate having a principal surface; a semiconductor component mounted on the principal surface; and an encapsulating resin layer formed of encapsulating resin so as to encapsulate the principal surface and side surfaces of the semiconductor component, the semiconductor component comprising a component body and bumps connected to a surface of the component body facing the substrate, the semiconductor component being mounted on the principal surface by connecting the bumps to the principal surface while the component body is spaced from the principal surface, an underfill layer being formed by filling a gap between the component body and the principal surface with an underfill resin, the underfill resin having an elastic modulus lower than that of the encapsulating resin, the underfill layer including a protruding portion existing outside an area in which the component body is projected onto the principal surface, the protruding portion being covered by the encapsulating resin layer, and a groove being formed in the encapsulating resin layer within an area in which the protruding portion is projected onto a surface of the encapsulating resin layer remote from the substrate.

2. The module according to claim 1, wherein the bottom of said groove extends into said protruding portion but does not reach said main surface.

3. The module according to claim 1 or 2, wherein, when viewed from a direction perpendicular to said main surface, said groove is formed so as to be spaced apart from said semiconductor component and to follow a side of said semiconductor component.

4. The module according to claim 3, wherein the groove is disposed so as to surround the semiconductor component when viewed in a direction perpendicular to the main surface.

5. The module described in claim 1 or 2, wherein, when viewed from a direction perpendicular to the main surface, the semiconductor component is arranged such that at least one edge of the semiconductor component follows the outline of the substrate, and the groove is spaced apart from the semiconductor component and is provided along one of the edges of the semiconductor component that does not follow the outline of the substrate.

6. The module according to claim 1, wherein the sealing resin and the underfill resin have different filler content conditions.

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