WO2021126723A1

WO2021126723A1 - Electronic component module and module substrate

Info

Publication number: WO2021126723A1
Application number: PCT/US2020/064745
Authority: WO
Inventors: Tetsunori TSUMURAYA
Original assignee: Molex, Llc
Priority date: 2019-12-20
Filing date: 2020-12-14
Publication date: 2021-06-24

Abstract

A connecting part 21A of the conductive plate 20A includes: a connecting surface 21a which faces upward and is connected to the terminals 31A of an electronic component 30 by solder B; and side surfaces 21c and 21d facing in the direction along the conductive plate 20A. The insulating part 11 includes a partition 11c adjacent to the connecting part 21A. A portion of the side surfaces 21c and 21d is exposed from the insulating part 11 and connected to the terminal 31A by solder B.

Description

ELECTRONIC COMPONENT MODULE AND MODULE SUBSTRATE

RELATED APPLICATIONS

[0001] This application claims the benefit of priority to Japanese Application No. 2019- 230390 filed December 20, 2019, and Japanese Application No. 2020-130920 filed July 31, 2020. The above-referenced applications are hereby incorporated by reference in their entirety.

TECHNICAL FIELD

[0002] The present disclosure relates to an electronic component module and a module substrate.

BACKGROUND ART

[0003] Electronic components such as high luminance LEDs and power transistors emit substantial heat when driven. Conventionally, a structure has been proposed in which a metal plate is utilized as a conductive member which supplies power to an electronic component having a high calorific value, in addition to efficiently releasing heat from the electronic component through the metal plate. For example, in Patent Document 1, two terminals of an LED are respectively connected to two bus bars that are metal plates. The heat of the LED is released from the bus bar to the opposite side of the LED (back side of the bus bar). In Patent Document 2, a conductive member to which the terminals of an LED are connected has a plate-like power supply connecting part to which an electric wire is connected and the heat of the LED is released from this power supply connecting part. In Patent Document 3, a heat dissipation sheet is pasted to the back surface of a bus bar on which an electronic component is mounted and the heat of the electronic component is emitted from this heat dissipation sheet. In Patent Document 1 to 3, two conductive members (bus bars) are held together by resin. [0004] Prior Art Documents: Patent Document 1 : Japanese Unexamined Patent Application Publication No. 2010-212322

Patent Document 2: Japanese Unexamined Patent Application Publication No. 2014-137963 Patent Document 3 : Japanese Unexamined Patent Application Publication No. 2019-87729

SUMMARY

[0005] In Patent Documents 1 to 3, the terminals of an electronic component are connected to a conductive member by solder. When driving the electronic component, the heat of the electronic component expands the terminals, after which the driving stop contracts the terminals. Due to such expansion and contraction, stress is generated in the solder connecting the terminals and the conductive member. This stress affects the durability of the solder and is not preferable in terms of the connection stability between the conductive member and the electronic component.

[0006] One example of an electronic component module proposed in the present disclosure includes: a module substrate which includes a conductive plate having a heat dissipation region and a connecting part, along with an insulating part that holds the conductive plate; and an electronic component having terminals connected to the connecting part by solder. The terminals have a terminal surface facing the connecting part. The insulating part has a part adjacent to the connecting part. The connecting part includes: a connecting surface which is exposed from the insulating part and faces the terminal surface; and a first side surface which faces in the direction along the connecting surface. At least a portion of the first side surface is exposed from the insulating part, and the connecting surface and at least the portion of the first side surface are connected to the terminal surface by the solder.

[0007] One example of a module substrate proposed in the present disclosure includes: a conductive plate having a heat dissipation region; and an insulating part that holds the conductive plate. The conductive plate has a connecting part connected to the terminals of an electronic component. The insulating part has a part adjacent to the connecting part. The connecting part includes: a connecting surface which is exposed from the insulating part and faces the terminal; and a first side surface which faces in the direction along the connecting surface, wherein at least a portion of the first side surface is exposed from the insulating part.

[0008] According to this electronic component module and this module board, the connection stability between the conductive member and the terminals of the electronic component can be improved.

[0009] Another example of a module substrate proposed in the present disclosure includes: a metal plate having a heat dissipation region; an insulating part holding the metal plate; and a conductor pattern formed on the insulating part. The insulating part includes a pattern base part which covers at least a portion of at least one surface of the conductive plate. The conductor pattern is formed on the surface of the pattern base part, with at least a portion of the conductor pattern overlapping the metal plate in a plan view of the metal plate.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1 is a perspective view of one example of the electronic component module proposed in the present disclosure.

[0011] FIG. 2A is a perspective view illustrating the module substrate illustrated in FIG. 1. In this figure, the conductor pattern depicted in FIG. 1 is omitted.

[0012] FIG. 2B is an enlarged view of FIG. 2A.

[0013] FIG. 3 is a perspective view of a conductive plate configuring the module substrate. [0014] FIG. 4 is a perspective view illustrating the underside of an electronic component module.

[0015] FIG. 5 is a plan view of the electronic component module.

[0016] FIG. 6 A is a cross sectional view taken at the section indicated by Vla-VIa in FIG. 5. [0017] FIG. 6B is an enlarged view of FIG. 6 A.

[0018] FIG. 7 is an enlarged view of a connection part possessed by the conductive plate. [0019] FIG. 8 is a cross sectional view taken at the section indicated by VIII- VIII in FIG. 5. [0020] FIG. 9 A is a perspective view of a conductive plate describing a first modified example of the module substrate. [0021] FIG. 9B is a cross sectional view of the module substrate taken at the section indicated by the line IXb-IXb in FIG. 9 A.

[0022] FIG. 10 is a cross sectional view illustrating a second modified example of the module substrate.

[0023] FIG. 11 is a cross sectional view illustrating a third modified example of the module substrate.

[0024] FIG. 12A is a plan view illustrating a fourth modified example of the module substrate. [0025] FIG. 12B is a cross sectional view taken at the section indicated by Xllb-XIIb in FIG. 12A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Hereinafter, an electronic component module 100 and a module substrate 10 will be described as one example of an electronic component module and a module substrate proposed in the present disclosure.

[0027] Hereinafter, the Yf direction and the Y2 direction illustrated in FIG. 1, etc. are respectively referred to as the front and the rear, the Z1 direction and the Z2 direction are respectively referred to as above and below, and the XI direction and the X2 direction are respectively referred to as the right and the left. These directions are used to describe the configuration and operation of each part of the module substrate 10 and the electronic component module 100 to illustrate the relative positional relationship of each part. Accordingly, these directions do not limit the orientation when the module substrate 10 and the electronic component module 100 are mounted on other apparatuses.

[0028] As illustrated in FIG. 1, the electronic component module 100 includes a module substrate 10, along with an electronic component 30 disposed above the module substrate 10 and mounted on the module substrate 10.

[0029] The electronic component 30 is a heating element, and is, for example, a power semiconductor. More specifically, the electronic component 30 is a high luminance light emitting diode (LED). The electronic component 30 is disposed, for example, such that the lower surface 30b is a flat surface and rectangular so as to emit light upward. A lens for controlling light from the electronic component 30 may be disposed above the electronic component 30. The electronic component 30 may be a power transistor. The electronic component 30 may have a first terminal 31 A and a second terminal 31 B on the lower surface 30b (see FIG. 6A). One of the two terminals 31 A and 3 IB may be an anode terminal, while the other thereof may be a cathode terminal.

[0030] As illustrated in FIG. 6B, in one example, the lower end (terminal surface 31a) of the terminals 31 A and 3 IB does not protrude from the lower surface 30b of the electronic component 30 (see FIG. 6B), but is disposed in a common plane with the lower surface 30b. The terminals 31 A and 3 IB are disposed inside the outer peripheral edge of the electronic component 30 (closer to the center P2 of the connecting region in the horizontal direction) (when the electronic component module 100 is viewed in a plan view), but are not exposed at the side surface 30c of the electronic component 30.

[0031] The module substrate 10 may include: a flat plate-shaped first conductive plate 20A and second conductive plate 20B (see FIG. 3) which are respectively electrically connected to the terminals and 3 IB of the electronic component 30; and an insulating part 11 (see FIG. 2 a), which is an insulator holding the two conductive plates 20A and 20B. The first conductive plate 20A and the second conductive plate 20B may have the same plate thickness.

[0032] The two conductive plates 20A and 20B are aligned in the direction along the upper surface 20a and the lower surface 20b, which are the respective plate surfaces (in the example of the electronic component module 100, the horizontal direction serving as the XI -X2 direction). A gap G1 (see FIGS. 3 and 6A) is formed between the edges of the conductive plates 20A and 20B. The conductive plates 20A and 20B are held by the insulating part 11, with the relative positions thereof fixed. The number of conductive plates held by the insulating part 11 may be more than two, and three or four may be used in accordance with the number of terminals of the electronic component 30, for example. Moreover, one electronic component module 100 may have multiple electronic components 30. In this case, the module substrate 10 may have a number of conductive plates corresponding to the number of the electronic components 30. [0033] Note that the insulating part 11 is formed of resin (for example, plastic resin) in the present embodiment. The insulating part 11 and the conductive plates 20 A and 20 B are integrally molded, for example, by a molding method referred to as injection molding, insert molding, or integral molding. That is, the molten resin, which is the material of the insulating part 11, is filled into the cavity with the conductive plates 20A and 20B disposed inside the cavity which is formed by a die. When the resin in the cavity hardens, the conductive plates 20A and 20B are held by the resin (insulating part 11). A portion of the conductive plates 20A and 20B is embedded in the insulating part 11 and fixed to the insulating part 11. The method for forming the insulating part 11 and the conductive plates 20 A and 20 B is not limited to the examples described herein.

[0034] The conductive plates 20A and 20B are members formed by punching from a metal plate (for example, an aluminum plate or a copper plate). While not limited thereto, the insulating material used in the insulating part 11 is preferably a liquid crystal polymer, ABS resin, nylon resin, etc. The material of the insulating part 11 may be any material that does not melt or soften due to the heat of the electronic component and can be integrally molded with the conductive plate. For example, the material of the insulating part 11 may be an insulating material including ceramic, glass, rubber, etc.

[0035] As illustrated in FIG. 6A, each of the conductive plates 20A and 20B includes an upper surface 20a and a lower surface 20b which face opposite each other in the vertical direction. The electronic component 30 is mounted on the upper surface 20a. The upper surface 20a of each of the conductive plates 20A and 20B may have one or more heat dissipation regions Ra (see FIG. 1). The lower surface 20b of each of the conductive plates 20A and 20B may also have one or more heat dissipation regions Rb (see FIG. 4). The heat dissipation regions Ra and Rb are regions exposed from the insulating part 11 at the upper surface 20a and the lower surface 20b of the conductive plates 20A and 20B.

[0036] Heat emitted by the electronic component 30 is transmitted to the conductive plates 20A and 20B through the terminal 31A and 3 IB and the connecting parts 21A and 2 IB described later and released from the heat dissipation regions Ra and Rb. In the heat dissipation regions Ra and Rb, the conductive plates 20A and 20B are exposed, such that the heat of the electronic component 30 is efficiently released. When the module substrate 10 is viewed in a plan view, in each of the conductive plates 20A and 20B, the heat dissipation region Ra of the upper surface 20a overlaps the heat dissipation region Rb of the lower surface 20b. This allows the heat of the electronic component 30 to be more efficiently released. The position and size of the heat dissipation region Ra on the upper surface 20a need not be equal to the position and size of the heat dissipation region Rb on the lower surface 20b.

[0037] A wide range of the upper surface 20a and the lower surface 20b of the conductive plates 20A and 20B is exposed from the insulating part 11, functioning as the heat dissipation regions Ra and Rb. For example, the heat dissipation region Ra may be in a larger range than half of the upper surface 20a, while the heat dissipation region Rb may be in a larger range than half of the lower surface 20b. Further, depending on the calorific value of the electronic component 30, the heat dissipation region may be ensured on only one surface of the upper surface 20a and the lower surface 20b. Moreover, the electronic component module 100 may have a heat dissipator (heat sink or heat pipe) which contacts the heat dissipation regions Ra and Rb.

[0038] As illustrated in FIG. 2 A, the insulating part 11 may include: an outer peripheral part 11a which holds the outer edges of the two conductive plates 20 A and 20B; and an intermediate part lib which is formed along the gap G1 between the two conductive plates 20A and 20B and filled into this gap Gl. Moreover, the insulating part 11 may have a pattern base part 11m in which the conductor pattern 13 is formed. The conductor pattern 13 and the pattern base 11m will hereinafter be described in detail Mounting holes 14 may be formed in the insulating part 11 and the conductive plates 20A and 20B to fix them to the apparatus in which they are used.

[0039] As illustrated in FIG. 2 A, the insulating part 11 may have a partition lie surrounding the connecting region in which the electronic component 30 is disposed. The connecting region is a region in which two connecting parts 21 A and 21 B described below are formed. In the reflow step in which the terminals 31A and 3 IB of the electronic component 30 are connected to the connecting parts 21 A and 2 IB, the partition lie can limit the range in which the solder B (see FIG. 6B) expands. [0040] As illustrated in FIG. 2B, the partition lie may surround the entirety of the two connecting parts 21A and 21B (entire connecting region). The partition lie is, for example, rectangular, and may include: a transverse partition lie which is disposed outside the two connecting parts 21 A and 2 IB in the horizontal direction and adjacent to the connecting parts 21 A and 2 IB; and a vertical partition 1 If which is disposed forward or rearward with respect to the two connecting parts 21A and 21B and adjacent to the connecting parts 21A and 21B. Moreover, the partition lie may have an intermediate partition llg formed between the two connecting parts 21 A and 2 IB.

[0041] As illustrated in FIG. 6B, the partition lie surrounds the electronic components disposed in the connecting region. The position of the upper surface of the partition lie is higher than the position of the lower surface 30b of the electronic component 30. Such a partition lie can guide the position of the electronic component 30 in the step of mounting the electronic component 30 on the module substrate 10.

[0042] The structure of the partition lie is not limited to an example of the electronic component module 100. For example, the partition lie need not necessarily be formed around the entire periphery of the connecting region. That is, the partition lie may be formed on only a portion of the outer edge of the connecting region. Further, the position of the upper surface of the partition lie may be lower than the position of the lower surface 30b of the electronic component 30.

[0043] As illustrated in FIG. 6A, the first conductive plate 20Amay include a first connecting part 21 A which is connected to the first terminal 31A of the electronic component 30 by the solder B, while the second conductive plate 20B may include a second connecting part 2 IB which is connected to the second terminal 3 IB of the electronic component 30 by the solder B. The first connecting part 21A is a part which is disposed on an opposing edge 20c (right edge illustrated in FIG. 3) in the first conductive plate 20A closer to the second conductive plate 20B, while the second connecting part 21B is a part disposed on the opposing edge 20c (left edge illustrated in FIG. 3) in the second conductive plate 20B closer to the first conductive plate 20A. The first connecting part 21A and the first terminal 31A each have a connecting surface 21a and a terminal surface 31a which face each other in the vertical direction. Similarly, the second connecting part 21B and the second terminal 3 IB each have a connecting surface 21a and a terminal surface 31a which face each other in the vertical direction. The connecting surface 21a and the terminal surface 31a are connected by solder B. In the electronic component module 100, the connecting surfaces 21A and 21B are disposed on the same plane as the upper surface 20a of the conductive plates 20A and 20B.

[0044] As illustrated in FIG. 6A, each of the connecting parts 21A and 21B may have side surfaces 21c and 21d which face in the direction (XI -X2 direction) along the connecting surfaces 21Aand 21B. In the electronic component module 100, the side surfaces 21c and 21d are formed in the vertical direction (Z1-Z2 direction) with respect to the upper surface 20a and the connecting surfaces 21Aand 21B. The side surface 21c is a surface facing the center P2 in the horizontal direction of the connecting region, while the side surface 21 d is a surface facing the side opposite the side surface 21c. The connecting surface 21a is connected to the upper edges of the side surfaces 21c and 2 Id. Hereinafter, the side surface 21c is referred to as the inner side surface, while the side surface 21d is referred to as the outer side surface. As described below, the side surfaces 21c and 2 Id may be connected to the connecting surface 21a via the R surface formed on comer parts 21g and 21h.

[0045] Each of the conductive plates 20A and 20B is a member formed by punching from a single metal plate. The connecting surface 21a is a portion of the upper surface of the metal plate, while the inner surface 21 c is a portion of the surface which defines the thickness of the metal plate. The outer surface 2 Id can be formed by pressing the upper surface 20a into a recess or by cutting the upper surface 20a of the metal plate by cutting to reduce the thickness of the metal plate.

[0046] As illustrated in FIG. 6B, the lower part of the inner surface 21c is covered by the insulating part 11 (more specifically, the intermediate partition 11c), while the upper part 21 e of the inner side surface 21c is not covered by the insulating part 11. The upper part 21e of the inner surface 21c is exposed from the intermediate partition llg formed between the two connecting parts 21A and 21B. As a result, the solder B includes not only the part formed on the connecting surface 21a, but also the part formed on the inner surface 21c (fillet Bl). [0047] Moreover, as illustrated in FIG. 6B, the lower part of the outer surface 21d is covered by the insulating part 11 (more specifically, the cover part llh described below), while the upper part 2 If of the outer surface 21d is not covered by the insulating part 11 but is exposed from the insulating part 11. Therefore, the solder B also includes a part (fillet B2) formed on the outer surface 2 Id.

[0048] According to this structure of the inner surface 21c and the outer surface 2 Id, the fillets B1 and B2 can improve the durability of the solder B to stress due to the thermal expansion and contraction of the terminals 31A and 3 IB, thereby improving the connection stability between the electronic component 30 and the module substrate 10.

[0049] As illustrated in FIG. 6B, the first terminal 31Ahas an edge 31c closer to the second terminal 3 IB in the direction along the terminal surface 31a, along with an edge 3 Id on the side opposite the edge 31c. The second terminal 3 IB also includes an edge 31c closer to the first terminal 31 A in the direction along the terminal surface 31a, along with an edge 3 Id on the side opposite to the edge 3 lc. Hereinafter, the edge 3 lc is referred to as the inner terminal edge, while the edge 3 Id is referred to as the outer terminal edge.

[0050] As illustrated in FIG. 6B, the positions of the inner side surface 21c and the outside surface 21d of the first connecting part 21 A may be between the position of the inner terminal edge 31c and the position of the outer terminal edge 31 d of the first terminal 31 A. That is, the inner surface 21c and the outer surface 21d may be disposed between the vertical surface P3 (which passes through the inner terminal edge 31c) and the vertical surface P4 (which passes through the outer terminal edge 3 Id). That is, the width of the first connecting part 21 A in the horizontal direction may be smaller than the width of the first terminal 21 A in the horizontal direction. As a result, the fillets B1 and B2 of the solder B are easily formed, thereby making it possible to further improve the durability of the solder B.

[0051] The same also holds true for the second connecting part 21B and the second terminal 3 IB. That is, the positions of the inner side surface 21c and the outer surface 2 Id of the second connecting part 21B in the horizontal direction may be between the position of the inner terminal edge 31c and the position of the outer terminal edge 31 d of the second terminal 31 B. The width of the second connecting part 21B in the horizontal direction may be smaller than the width of the second terminal 2 IB in the horizontal direction.

[0052] Note that the relative positions between the side surfaces 21c and 21d and the terminal edges 31c and 3 Id are not limited to the example illustrated in FIG. 6B.

• For example, the position of the inner surface 21c in the horizontal direction may be the same as the position of the inner terminal edge 31c, or may be disposed inside the inner terminal edge 31c (closer to the center P2 of the connecting region in the horizontal direction). In this case, the position of the outer surface 2 Id in the horizontal direction may be between the inner terminal edge 31c and the outer terminal edge 3 Id of the terminals 31A and 31B.

• In another example, the position of the outer surface 21 d in the horizontal direction may be the same as the position of the outer terminal edge 3 Id, or may be outside the position of the outer terminal edge 3 Id. In this case, the position of the inner surface 21c in the horizontal direction may be between the inner terminal edge 31c and the outer terminal edge 3 Id of the terminal 31 A and 3 IB.

• In yet another example, the insulating part 11 may be formed so as not to cover the entire inner surface 21c. That is, the partition lie need not have the intermediate partition llg between the first connecting part 21 A and the second connecting part 2 IB.

• In yet another example, the insulating part 11 (more specifically, the cover part 1 lh described below) may be formed so as not to cover the entire outer surface 2 Id.

• In yet another example, one of the two side surfaces 21c and 21 d of the connecting parts 21 A and 21B is entirely covered by the insulating part 11, while the entire or the upper part of the other of the two side surfaces 21c and 21d may be exposed from the insulating part 11.

[0053] As illustrated in FIG. 6A, the conductive plates 20A and 20B may have a low surface 22a which is adjacent to the outer surface 21d and faces upward. The low surface 22a extends outward from the outer surface 2 Id (towards the side opposite the center P2 of the connecting region) and is disposed so as to be lower than the connecting surface 21a. As illustrated in FIG. 6B, the partition lie of the insulating part 11 (see FIG. 2b) may have a cover part 11 h which covers this low surface 22a. The cover part llh is a part extending from the transverse partition lie towards the center P2 in the horizontal direction of the connecting region. According to this structure, in the reflow step in which the terminals 31A and 3 IB are connected to the connecting parts 21A and 21B, the cover part llh can further limit the range in which the solder B expands.

[0054] If the cover part 1 lh is not present, the solder B can also expand to the low surface 22a in the reflow step. In this case, the position of the electronic component 30 in the horizontal direction is less likely to be determined. As described above, the electronic component 30 is an LED. When the position of the electronic component 30 shifts from the regular position, the light of the electronic component 30 shifts from the lens. Moreover, when the solder B expands to the low surface 22a, the thickness of the solder B decreases, making it difficult to form the fillets B1 and B2. In the example of the electronic component module 100, the cover part 1 lh of the insulating part 11 covers the low surface 22a of the conductive plates 20 A and 20B, thereby allowing the expansion of the solder B to be appropriately limited and the position of the electronic component 30 to be appropriately adjusted. Moreover, because the thickness of the solder B can be ensured, it is easy to form fillets B1 and B2 having an appropriate shape (specifically, a triangle).

[0055] As illustrated in FIG. 6B, the end of the cover part llh may be disposed closer to the center P2 of the connecting region than the side surfaces 30c and 30d of the electronic component 30. That is, when the electronic component module 100 is viewed in a plan view, a portion of the cover part 1 lh may overlap the electronic component 30. As a result, the cover part llh can further limit the range in which the solder B expands in the reflow step.

[0056] As illustrated in FIG. 6B, the cover part llh may cover the lower part of the outer surface 21d of the connecting parts 21A and 21B. As a result, the cover part llh can further limit the range in which the solder B expands in the reflow step. As a result, for example, even when the electronic component 30 shifts from the regular position in the reflow step, the position of the electronic component 30 is appropriately adjusted in accordance with the tension of the solder B.

[0057] In the example of the electronic component module 100, as illustrated in FIG. 6B, the cover part llh may include: a high part lli which extends from the transverse partition lie towards the center P2 of the connecting region; and a low part llj which further extends towards the center P2 from the high part lli and is lower than the high part lli. The inner part of the high part lli is disposed below the electronic component 30. The low part llj is disposed below the terminals 31 A and 3 IB.

[0058] Note that the insulating part 11 need not have the cover part llh. The entire outer surface 21d of the connecting parts 21A and 21B need not be covered by the insulating part 11. Moreover, all or a portion of the low surface 22a extending from the outer surface 21d need not be covered by the cover part llh.

[0059] As illustrated in FIG. 3, the conductive plates 20A and 20B may have a recessed part 22 which is adjacent to the connecting parts 21A and 21B in the horizontal direction. The first conductive plate 20A includes a recessed part 22 which is disposed so as to be adjacent to the left side of the first connecting part 21A and inside the partition lie, while the second conductive plate 20B may include a recessed part 22 which is disposed so as to be adjacent to the right side of the second connecting part 21 B and inside the partition lie. The lower surface of the recessed part 22 is the low surface 22a. By forming the recessed part 22, the position of the upper surface (connecting surface 21a) of the connecting parts 21A and 21 B is higher than the position of the low surface 22a. The cover part llh of the insulating part 11 is formed in the recessed part 22.

[0060] The recessed part 22 is formed by pressing the metal plate, which is the material of the conductive plates 20Aand 20B. Consequently, as illustrated in FIG. 6A, the lower surface 20b of the conductive plates 20A and 20B bulges downward at the position of the recessed part 22. The height of the connecting surface 21a, which is the upper surface of the connecting parts 21A and 2 IB, is the same as the height of the upper surface 20a in the heat dissipation region Ra.

[0061] Note that the recessed part 22 need not be formed in the conductive plates 20 A and 20B. In this case, the connecting parts 21A and 21B may protrude above the other parts of the conductive plates 20A and 20B (the parts at which the heat dissipation region Ra is formed). In so doing, the outer side surface 21d can be formed on the connecting parts 21Aand 21B. [0062] As illustrated in FIG. 7, the first connecting part 21 A may have an R surface at the comer parts 21g and 21h between the connecting surface 21a and the side surfaces 21c and 2 Id. The R surface is a curved surface such as an arc curved around the center line C parallel to the connecting surface 21a and the side surfaces 21c and 21d. Stress acting on the solder B can be dispersed by the R surface. The R radius (d indicated in FIG. 7) is 0.02 mm or greater, more preferably 0.05 mm or greater. For example, if the conductive plates 20A and 20B are formed by pressing, the R surface may be a Darley (curved surface) formed at the comer parts 21g and 21h as a result of the punching of the conductive plates 20A and 20B.

[0063] As illustrated in FIG. 4, the module substrate 10 may have a connector part E. The connector part E includes a housing 11s and terminals 24a and 24b. As illustrated in FIG. 3, the terminals 24a and 24b are respectively formed on the conductive plates 20Aand 20B. That is, the terminals 24a and 24b are portions of the metal plate configuring the conductive plates 20A and 20B. The terminals 24a and 24b are formed, for example, in a pin shape and bent with respect to the heat dissipation regions Ra and Rb of the conductive plates 20A and 20B. The housing 11 s is a portion of the insulating part 11 and is formed together with other parts (for example, the outer peripheral part 11a and the partition lie) in the step of molding the insulating part 11. The housing 11s houses the terminals 24a and 24b.

[0064] In the example of the electronic component module 100, the terminals 24a and 24b extend downwards from the conductive plates 20A and 20B. As illustrated in FIG. 8, the housing 11s has a cylindrical shape which opens downward, with the terminals 24a and 24b disposed therein. Unlike the electronic component module 100, the terminals 24a and 24b may extend upwards from the conductive plates 20A and 20B or may extend in the direction along the conductive plates 20A and 20B (for example, to the right or front). As illustrated in FIG. 4, the connector 91 provided at the end of a cable 90 is connected to the connector part E.

[0065] As illustrated in FIG. 1, a conductor pattern 13 may be formed on the surface of the insulating part 11. The conductor pattern 13 may have multiple conductor paths 13a to 13c. A passive component (such as a resistor or capacitor) or a sensor necessary to drive the electronic component 30, for example, may be mounted on the conductor pattern 13.

[0066] The conductor pattern 13 is formed, for example, by the following method. A conductive ink (for example, silver ink) is disposed on the upper surface of the insulating part 11 by a printing method or a dispensing method. The part at which the ink is disposed is thickened by electrolytic copper plating. This thickened part serves as the conductor pattern 13. The method for forming the conductor pattern 13 is not limited thereto. For example, a conductive paste may be disposed on the upper surface of the insulating part 11 utilizing printing or a mask and may be utilized as a conductor pattern 13.

[0067] The insulating part 11 may have the pattern base part 11m formed on the surfaces of the conductive plates 20Aand 20B. The pattern base part 11m extends, for example, inward from the outer peripheral part 1 la of the insulating part 11. The conductor pattern 13 is formed on the surface of the pattern base part 11m. Because the pattern base part 11m is formed on the conductive plates 20A and 20B, at least a portion of the conductor pattern 13 overlaps the conductive plates 20A and 20B in a plan view of the conductive plates 20A and 20B. According to this structure, the conductor pattern 13 is formed by effectively utilizing the area of the conductive plates 20A and 20B, making it possible to suppress upsizing of the module substrate 10. Moreover, the degree of freedom of the shape of the conductor pattern 13 can be increased.

[0068] A connection hole 1 In (see FIG. 2A) may be formed in the pattern base part 11m. This connection hole 1 In reaches the first conductive plate 20A, wherein the first conductive plate 20A is exposed inside the connection hole lln. The end of the conductor path 13b is formed inside the connection hole lln and connected to the first conductive plate 20A. Moreover, an inclined surface lip (see FIG. 2A) is formed at the edge of the pattern base part 11m. The lower edge of the inclined surface lip is disposed on the second conductive plate 20B. The end of a conductor path 13c extends through the inclined surface lip and is connected to the upper surface 20a of the second conductive plate 20B. [0069] As illustrated in FIG. 3, the module substrate 10 may have a terminal member 25 formed by punching from a metal plate, similar to the conductive plates 20A and 20B. At least a portion of the terminal member 25 may be disposed on the same plane as the conductive plates 20A and 20B. That is, the horizontal plane intersecting the conductive plates 20A and 20B may intersect at least a portion of the terminal member 25. The end 25a of the terminal member 25 is exposed at the upper surface of the insulating part 11 (see FIG. 2A). The end of the conductor path 13a is formed on the end 25a of the terminal member 25 and electrically connected to the terminal member 25.

[0070] As described above, the module substrate 10 includes the conductive plates 20A and 20B having heat dissipation regions Ra and Rb, along with the insulating part 11 holding the conductive plates 20A and 20B. The electronic component 30 is disposed above the module substrate 10 and has the terminals 31A and 31B. The conductive plates 20A and 20B respectively include connecting parts 21 A and 2 IB connected to the terminals 31A and 3 IB by solder B. The connecting parts 21A and 2 IB include: a connecting surface 21a which faces upward and is connected to the terminals 31 A and 3 IB by the solder B; and side surfaces 21c and 21d which are formed in the direction intersecting the direction along the upper surface 20a and the lower surface 20b of the conductive plates 20A and 20B. The insulating part 11 includes a part (partition lie) adjacent to the connecting parts 21 A and 21 B. A portion of the side surfaces 21c and 21d is not covered by the insulating part 11 but rather exposed and connected to the terminals 31 Aand 3 IB by the solder B. According to this structure, the fdlets B1 and B2 of the solder B can improve the durability of the solder B to stress due to the thermal expansion and contraction of the terminals 31Aand 31B, consequently improving the connection stability between the electronic component 30 and the module substrate 10.

[0071] Note that the structures of the module substrate and the electronic component module proposed in the present disclosure are not limited to the module substrate 10 and the electronic component module 100 described above. FIGS. 9A to 12B are modified examples of the module substrate and the electronic component module. Hereinafter, the module substrate 10 and the electronic component module 100 described above will be described focusing on different points. In the structures illustrated in FIGS. 9Ato 12B, the description of the module substrate 10 and the electronic component module 100 may be applied to items not described. [0072] In the example of the module substrate 10, the recessed part 22 is formed outside the connecting parts 21A and 21B in the horizontal direction. That is, in the first conductive plate 20 A, the recessed part 22 is formed only on the left of the first connecting part 21 A, while, in the second conductive plate 20B, the recessed part 22 is formed only on the right of the second connecting part 2 IB (see FIG. 3). In contrast, as illustrated in FIG. 9A, in the first conductive plate 20A, the recessed part 22 may be formed so as to surround three sides of the connecting part 21 A. That is, the recessed part 22 may have parts 22e, 22f, and 22g respectively disposed on the left, front, and back of the connecting part 21 A. Similarly, in the second conductive plate 20B, the recessed part 22 may be formed so as to surround three sides of the connecting part 2 IB.

[0073] In the example illustrated in FIG. 9B, the connecting part 21A includes side surfaces 21i and 2 lj in addition to the side surface 21d (see FIG. 6B). The side surfaces 2 li and 21j face in the direction along the connecting surface 21a and in the direction intersecting the direction (left side) faced by the side surface 21d (see FIG. 6B). Specifically, the side surface 21i faces forward, while the side surface 21j faces rearward. A portion of the cover part llh formed in the recessed part 22 reaches the side surfaces 21i and 21j. The upper part of the side surface 21i and 2 lj is exposed from the cover part llh. Afillet B5 of the solder B is formed along this exposed upper part. This structure can improve the accuracy of the position of the electronic component 30 in the anteroposterior direction. Moreover, the formation of the fillet B5 can further improve the connection stability between the electronic component 30 and the conductive plate 20A. Note that each of the side surfaces 21i and 21j is disposed between the front edge and the back edge of the first terminal 31A of the electronic component 30. This may allow the fillet B5 to be easily formed. Note that in FIGS. 9A and 9B, only the first conductive plate 20A is illustrated; however, the second conductive plate 20B also has the same structure.

[0074] Yet another example will be described. In the example of the module substrate 10, the recessed part 22 adjacent to the connecting parts 21A and 21B is formed on the conductive plates 20A and 20B. However, this recessed part 22 need not necessarily be formed. In the module substrate 210 illustrated in FIG. 10, conductive plates 220A and 220B do not include the recessed part 22, and a connecting surface 221a, which is the upper surface of connecting parts 221A and 221B, is disposed in the same plane as the heat dissipation region Ra of the conductive plates 220A and 220B.

[0075] Similar to the example illustrated in FIG. 6A, etc., the connecting parts 221Aand221B include an inner surface 21c which faces the center P2 of the connecting region. The upper part of the inner surface 21c is exposed from the insulating part 11 (more specifically, the intermediate partition llg). As a result, the solder B includes the fillet B1 connected to the inner surface 21c. The position of the inner surface 21c in the horizontal direction is disposed between the position of the inner terminal edge 231c and the position of the outer terminal edge 23 Id in the horizontal direction of the terminal surface 231a of the terminals 231 A and 23 IB. As a result, the fillet B1 in contact with the inner surface 21c is easily formed. Because the conductive plates 220A and 220A do not include the recessed part 22, the connecting parts 221 A and 22 IB do not include the outer surface 21 d facing opposite the inner surface 21c, unlike the example illustrated in FIG. 6B, etc.

[0076] In the example illustrated in FIG. 10, terminals 231 A and 23 IB of an electronic component 230 are disposed along the outer peripheral edge of the electronic component 230 and exposed at the side surface 230c of the electronic component 230. The solder B includes a fillet B3 connected to the side surface of the terminals 231A and 23 IB.

[0077] In the module substrate 210, the insulating part 11 also includes a partition lie which surrounds the connecting region. Unlike the example illustrated in FIG. 6A, etc., the partition lie does not have a cover part 1 lh extending towards the center of the connecting region. In this case as well, in the reflow step in which the terminals 231 A and 23 IB of the electronic component 230 are connected to the connecting parts 221 A and 22 IB, the inner surface llq of the partition lie can limit the range in which the solder B expands.

[0078] In the example illustrated in FIG. 10, the inner surface 21c of the connecting parts 221 A and 22 IB need not be exposed from the insulating part 11. In the module substrate 310 illustrated in FIG. 11, the entire inner surface 21c is covered by the intermediate partition 31 lg of the insulating part 11. In this case, the terminals 231Aand231B of the electronic component 230 are preferably disposed along the outer peripheral edge of the electronic component 230, in addition to having side surfaces which are exposed at the side surfaces 230c of the electronic component 230. In so doing, the fdlet B3 connected to the side surfaces of the terminals 231A and 23 IB is formed on the solder B. Note that in the module substrate 310 illustrated in FIG. 11, the insulating part 11 also has the partition lie which surrounds the electronic component 230. The inner surface 11 q of the partition 11 can limitthe range of the solder B expanding in the reflow step.

[0079] As yet another example, the conductive plates 20A and 20B may have an air flow path which passes through the conductive plates 20A and 20B in the heat dissipation regions Ra and Rb. FIGS. 12A and 12B illustrate a module substrate 410 with an example of such a structure. FIG. 12A is a plan view of the module substrate 410, while FIG. 12B is a cross sectional view taken at the section indicated by the line Xllb-XIIb in FIG. 12A.

[0080] In the examples illustrated in these figures, conductive plates 420A and 420B include multiple louvers 426 disposed in the heat dissipation regions Ra and Rb. The louvers 426 are arranged, for example, in the horizontal direction and the anteroposterior direction. The louver 426 is the part at which a portion of the metal plate configuring the conductive plates 420A and 420B is bent upward or downward. The louver 426 forms an air flow path F which passes through the conductive plates 420A and 420B. According to this structure, the amount of air passing through the conductive plates 420A and 420B can be increased while maintaining the area of the conductive plates 420A and 420B, making it possible to improve the heat dissipation performance of the conductive plates 420A and 420B.

[0081] As yet another example, the conductive plates 20A and 20B may have a recessed part or a protruding part in at least one of the heat dissipation region Ra of the upper surface 20a or the heat dissipation region Rb of the lower surface 20b. According to this structure, the surface area of the conductive plates 20A and 20B in the heat dissipation regions Ra and Rb increases, making it possible to improve the heat dissipation performance of the conductive plates 20A and 20B. [0082] As yet another example, depending on the type of electronic component, the number of the conductive plates possessed by the module substrate may be one. In this case, one of the terminals possessed by the electronic component may be connected to an external apparatus.

[0083] B Solder, Bl, B2, and B3 Fillet, E Connector part, F Air flow path, 10 Module substrate, 11 Insulating part, 11a Outer peripheral part, lib Intermediate part, lie Partition, lie Transverse partition, Ilf Vertical partition, llh Cover part, lli High part, llj Low part, lln Connection hole, lip Inclined surface, llq Inner surface, 11s Housing, 13 Conductor pattern, 13a, 13b, and 13c Conductor path, 14 Mounting hole, 20Aand 20B Conductive plate, 20a Upper surface, 20b Lower surface, 20c Opposing edge, 21 A and 2 IB Connecting part, 21a Connecting surface, 21c and 21d Side surface, 21e Upper part, 2 If Upper part, 22 Recessed part, 22a Low surface, 24a and 24b Terminal, 25 Terminal member, 25a End, 30 Electronic component, 30b Lower surface, 30c Side surface, 31A and 3 IB Terminal, 31a Terminal surface, 31c and 3 Id Terminal edge, 90 Cable, 91 Connector, G1 Gap, P2 Center of the connecting region, Ra and Rb Heat dissipation region, 100 Electronic component module, 210 Module substrate, 220A and 220B Conductive plate, 221A and 221B Connecting part, 221a Connecting surface, 230 Electronic component, 230c Side surface, 231 A and 23 IB Terminal, 231a Terminal surface, 231c and 23 Id Terminal edge, 23 Id Outer terminal edge, 310 Module substrate, 410 Module substrate, 420Aand 420B Conductive plate, 426 Louver.

Claims

1. An electronic component module, comprising: a module substrate which includes a conductive plate having a heat dissipation region and a connecting part, along with an insulating part that holds the conductive plate; an electronic component having terminals connected to the connecting part by solder, wherein: the terminals have a terminal surface facing the connecting part, the insulating part has a part adjacent to the connecting part, and the connecting part includes a connecting surface which is exposed from the insulating part and faces the terminal surface; and a first side surface which faces in the direction along the connecting surface, wherein: at least a portion of the first side surface is exposed from the insulating part, and the connecting surface and at least the portion of the first side surface are connected to the terminal surface by the solder.

2. The electronic component module according to claim 1, wherein: the terminal surface includes: a first terminal edge serving as one edge of the terminal surface, and a second terminal edge serving as an edge opposite the first terminal edge, and the position of the first side surface in the direction along the terminal surface is between the position of the first terminal edge and the position of the second terminal edge.

3. The electronic component module according to claim 1, wherein: the connecting part includes a second side surface facing opposite the first side surface in the direction along the connecting surface, and at least a portion of the second side surface is also exposed from the insulating part and connected to the terminal surface by the solder.

4. The electronic component module according to claim 3, wherein: the terminal surface includes: a first terminal edge serving as one edge of the terminal surface in the direction along the terminal surface, and a second terminal edge serving as an edge opposite the first terminal edge; and the position of the first side surface and the position of the second side surface in the direction along the terminal surface are between the position of the first terminal edge and the position of the second terminal edge.

5. The electronic component module according to claim 1, wherein: the conductive plate has a low surface adjacent to the connecting part, the low surface faces a terminal surface of the electronic component, disposed further from the terminal surface than the connecting surface, and connected to the first side surface, and the part of the insulating part includes a cover part covering the low surface.

6. The electronic component module according to claim 5, wherein the cover part covers a portion of the first side surface.

7. The electronic component module according to claim 1 , wherein the connecting part includes an R surface at a comer part between the connecting surface and the first side surface.

8. The electronic component module according to claim 1, wherein the insulating part is formed of resin.

9. A module substrate, comprising: a conductive plate having a heat dissipation region; and an insulating part that holds the conductive plate; wherein: the conductive plate has a connecting part connected to the terminals of an electronic component, the insulating part has a part adjacent to the connecting part, the connecting part includes: a connecting surface which is exposed from the insulating part and faces the terminal, and a first side surface which faces in the direction along the connecting surface, and at least a portion of the first side surface is exposed from the insulating part.

10. A module substrate, comprising: a metal plate having a heat dissipation region; an insulating part holding the metal plate; and a conductor pattern formed on the insulating part; wherein: the insulating part includes a pattern base part which covers at least a portion of at least one surface of the conductive plate, and the conductor pattern is formed on the surface of the pattern base part, with at least a portion of the conductor pattern overlapping the metal plate in a plan view of the metal plate.

11. The module substrate according to claim 10, wherein: the metal plate has an exposed part exposed from the insulating part, and the conductor pattern is connected to the exposed part of the metal plate.

12. The module substrate according to claim 10, further comprising a conductive terminal member formed separately from the metal plate and held by the insulating part; wherein: the terminal member has a part exposed from the insulating part, and the conductor pattern is connected to the part of the terminal member.

13. An electronic component module, comprising: the module substrate according to claim 10; and an electronic component; wherein: the metal plate has a part exposed from the insulating part, and the electronic component is disposed on the exposed part.

14. The electronic component module according to claim 13, wherein: the electronic component includes: terminals; and a connecting surface facing the terminals at a part at which the electronic component of the metal plate is disposed; and the terminals are connected to the connecting surface so as to be electrically conducted.