JP2007042700A - Surface-mounting semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface-mounting semiconductor device which can be easily manufactured with few number of processes, while at the same time, maintaining a high heat dissipation properties. <P>SOLUTION: In manufacturing the semiconductor light-emitting device 1; a lead frame 4 mounted with a light-emitting element 2 is held between metal molds, and resin is injected into a space formed by the lead frame and the metal molds to form a case 3. Then a lead frame 5 on the light-emitting element mounted side and a lead frame 6 on the wire side, which are made projecting from the short side-side side face of the case 3, are bent along the side face and the bottom face of the case 3. The heat, generated by the light-emitting element 2, is transmitted from the mounting plane 5a of the light-emitting element mounted-side lead frame 5 to the side face 5b, and then is dissipated from the bottom face 5c to the substrate side. At the same time, the heat transmitted to a heat sink 7 is dissipated into the air. Since the heat sink 7 is formed over nearly the entire surface of the long side-side side faces of the case 3, a large amount of heat can be dissipated into the air from these faces. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a surface mount semiconductor device mounted on a substrate.

  As a conventional surface mount semiconductor device, for example, there is one described in Patent Document 1. 4 is a perspective view of a conventional surface mount semiconductor device, FIG. 5 is a cross-sectional view of FIG. 4, and FIG. 6 is a perspective view of the lead frame of FIG. The surface-mount semiconductor device 21 shown in FIG. 4 is formed by embedding a lead frame 23 in a substantially cubic resin package 24 provided with a recess 22 for accommodating a light emitting diode 25. As shown in FIGS. 4 to 6, the lead frame 23 extends from the upper end of the reflective surface 23a exposed on the surface of the recess 22 toward the side surface of the resin package 24, and further on the surface from the side surface toward the lower surface 24f. A portion that is bent and stretched in an exposed state and bent along the surface of the lower surface 24f is a terminal electrode 23c. The terminal electrode 23c continues to bend and extend into the resin package 24, contacts the lower end of the reflecting surface 23a, and is exposed on the surface of the recess 22. This exposed portion serves as a connection electrode 23b on which the light emitting diode 25 is mounted. In addition, a part of the lead frame 23 exposed on the side surface is extended to the adjacent side surfaces to form the side electrode 23d so that the resin package 24 can be mounted on the substrate in both the upward and lateral directions.

  In the surface-mounted semiconductor device 21 described in Patent Document 1, first, a lead frame 23 is formed by progressively drawing and bending a belt-shaped aluminum plate into a three-dimensional shape, and resin molding is performed by insert molding the lead frame 23. This is manufactured by molding a portion into a resin package 24, mounting a light emitting diode 25 on the connection electrode 23 b of the lead frame 23, sealing with a transparent resin 26, and sealing the recess 22 with a lid member 27. The

In the surface mount semiconductor device 21 described in Patent Document 1, the connection electrode 23b of the lead frame 23 on which the light emitting diode 25 is mounted and the terminal electrode 23c in contact with the substrate are continuous, and the light is emitted because the distance is short. Heat released from the diode 25 is easily transmitted to the substrate, and heat can be efficiently released to the substrate side.
JP 2004-335740 A

  However, as shown in FIG. 6, the lead frame 23 of the surface mount semiconductor device 21 described in Patent Document 1 has a very complicated shape, and the shape of the die for punching the strip-shaped aluminum plate is also complicated. It becomes. In addition, in order to form the connection electrode 23b on which the light emitting diode 25 is mounted, a process of making this strip-shaped aluminum plate into a three-dimensional shape is required, which not only increases the number of processes but also makes it difficult to manufacture.

  Accordingly, an object of the present invention is to provide a surface mount semiconductor device that can be easily manufactured with a small number of steps while maintaining high heat dissipation.

  The surface-mount type semiconductor device according to the present invention has a semiconductor element housed in a recess of a case and a lead frame that is conductively connected to the semiconductor element is protruded from a side surface of the case, and the protruding lead frame is further extended from the side surface to the bottom surface. In the surface mount type semiconductor device mounted on the substrate in a state bent along the lead frame, the lead frame bent along the side surface, from the bottom surface, along at least one other side surface adjacent to the side surface, Further, a bent heat radiating plate is provided, and the heat radiating plate is formed on almost the entire other side surface.

  According to the surface mount semiconductor device of the present invention, it is possible not only to radiate heat to the substrate side on which the surface mount semiconductor device is mounted, but also to efficiently release heat into the air from the heat radiating plate. A surface-mount semiconductor device having In addition, the heat radiating plate can be easily manufactured because the lead frame only needs to be bent along the other side surface of the case after the lead frame is bent along the bottom surface from the side surface of the case.

  In the first invention of the present application, a lead frame that houses a semiconductor element in a recess of the case and is electrically connected to the semiconductor element protrudes from the side surface of the case, and the protruding lead frame is further bent from the side surface along the bottom surface. In a surface-mount type semiconductor device mounted on a substrate in a bent state, a lead frame bent along the side surface is further bent from the bottom surface along at least one other side surface adjacent to the side surface. And the heat sink is formed on substantially the entire other side surface.

  The heat-radiating plate is provided on at least one other side surface adjacent to the side surface from which the lead frame is projected, and is formed on substantially the entire other side surface. It is possible to efficiently release heat not only to the substrate side on which the mounting type semiconductor device is mounted but also from the heat sink to the air. In addition, the heat radiating plate can be manufactured easily because the lead frame protruding from the side surface of the case only needs to be bent along the bottom surface from the side surface, and then further bent along the other side surface of the case.

  According to a second aspect of the present invention, in the first aspect of the present invention, the semiconductor element is die-bonded to a lead frame.

  The semiconductor element that is the source of heat is die-bonded on the lead frame, and the heat generated from the semiconductor element can be directly transferred from the lead frame to the heat sink, so that not only the board but also the air It becomes possible to dissipate heat efficiently.

(Embodiment)
Hereinafter, a surface mount semiconductor device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view of a surface mount semiconductor device according to an embodiment of the present invention. 2A and 2B are diagrams showing a surface-mounted semiconductor device according to an embodiment of the present invention, where FIG. 2A is a plan view, FIG. 2B is a bottom view, FIG. 2C is a left side view, and FIG. FIG. FIG. 3 is a development view of the lead frame of the surface mount semiconductor device according to the embodiment of the present invention.

  The surface mount type semiconductor device according to the present embodiment is a semiconductor light emitting device 1, and a light emitting element 2, which is a semiconductor element mounted on a lead frame 4 by die bonding, is formed in a substantially rectangular parallelepiped with a resin material. The recess 3a is housed, and the recess 3a is sealed with a sealing resin (not shown).

  As shown in FIG. 3, the lead frame 4 is composed of a light emitting element mounting side lead frame 5 and a wire side lead frame 6, and a strip-like thin plate material made of a metal material such as an aluminum plate, an iron plate or a copper plate is extracted. It is integrally formed with the gap 4a separated by being pulled out by a mold.

  As shown in FIGS. 2 and 3, the light emitting element mounting side lead frame 5 includes a light emitting element mounting surface 5a, a side surface portion 5b protruding from the side surface on the short side of the case 3 and bent along the side surface, A bottom surface portion 5c that is further bent along the bottom surface from the side surface on the short side of the case 3, and a heat sink 7 that is formed continuously from the bottom surface portion 5c and is bent along the side surface on the long side of the case 3. It consists of.

  In order to efficiently dissipate the heat generated in the light emitting element 2, the heat radiating plate 7 is formed in substantially the same shape as the side surface on the long side so as to be formed on almost the entire side surface on the long side.

  The wire-side lead frame 6 includes a wire bonding surface 6a to which the wire 2a is bonded, a side surface portion 6b that protrudes from a side surface on the short side of the case 3 and is bent along the side surface, and a short side of the case 3 It is comprised by the bottom face part 6c bent further along the bottom face from the side surface of the side.

  In order to efficiently dissipate the heat generated in the light emitting element 2, the bottom surface portion 5c of the light emitting element mounting side lead frame 5 is formed larger than the bottom surface portion 6c of the wire side lead frame 6 as shown in FIG. Has been. In order to further improve heat dissipation, the bottom surface portion 5c may be formed as large as possible so as not to contact the bottom surface portion 6c. 2C and 2D, the side surface portion 5b of the light emitting element mounting side lead frame 5 is also formed wider than the side surface portion 6b of the wire side lead frame 6.

  Next, a method for manufacturing the semiconductor light emitting device 1 of the present embodiment will be described.

  First, a light emitting element mounting side lead frame 5 and a wire side lead frame 6 are formed by removing a strip-shaped thin plate material made of a metal material such as an aluminum plate, an iron plate, or a copper plate with a punching die. Then, the light emitting element 2 is die-bonded to the light emitting element mounting surface 5 a of the light emitting element mounting side lead frame 5, and the wire 2 a of the light emitting element 2 is bonded to the wire bonding surface 6 a of the wire side lead frame 6. The lead frame 4 in this state is held between molds for resin molding, and the case 3 is molded by injecting resin into a box-like space formed between the lead frame 4 and the mold. At this time, the light emitting element 2 is housed in the recess 3 a of the case 3, and the side surface portions 5 b and 6 b of the light emitting element mounting side lead frame 5 and the wire side lead frame 6 are side surfaces on the short side of the case 3, respectively. It is in a state protruding from.

  When the molding of the case 3 is completed, the case 3 is removed from the mold, and the side surface portions 5b and 6b of the light emitting element mounting side lead frame 5 and the wire side lead frame 6 are bent toward the bottom surface along the side surface on the short side of the case 3. . Then, the bottom surface portions 5 c and 6 c of the light emitting element mounting side lead frame 5 and the wire side lead frame 6 are bent along the bottom surface from the side surface on the short side of the case 3. In the light emitting element mounting side lead frame 5, the heat sink 7 is further bent along the long side surface of the case 3. Finally, the light emitting element 2 is sealed by injecting a sealing resin into the recess 3a. The semiconductor light emitting device 1 is manufactured through the above steps.

  The semiconductor light emitting device 1 of the present embodiment is used by being mounted on a substrate (not shown), but the heat generated in the light emitting element 2 is transferred from the light emitting element mounting surface 5a of the light emitting element mounting side lead frame 5 to the side surface portion 5b. At the same time, heat is radiated from the bottom surface portion 5c to the substrate side, and at the same time, heat transmitted from the bottom surface portion 5c to the heat radiating plate 7 is radiated into the air. Since the heat radiating plate 7 is formed on almost the entire side surface of the long side of the case 3, a large amount of heat can be released from this surface into the air.

  As described above, the semiconductor light emitting device 1 according to the present embodiment can be resin-molded in a state where the light-emitting element 2 is bonded to a strip-shaped thin plate material without the three-dimensional molding of the lead frame in advance, and is formed by resin molding. A semiconductor light emitting device having high heat dissipation can be easily manufactured by simply bending the light emitting element mounting side lead frame 5 and the wire side lead frame 6 protruding along the side and bottom surfaces of the case 3.

  In addition, since the heat sink 7 is integrally formed with the lead frame 4 and has conductivity, it can also be used as a terminal on the light emitting element mounting side. Moreover, although the heat sink 7 of this Embodiment was formed in the both sides | surfaces of the long side of case 3, when the amount of heat generation of the light emitting element 2 is not large, even if it is the structure provided only in one side Good. Further, although it is possible to form the heat radiating plate 7 continuously with the side surface portion 5b of the light emitting element mounting side lead frame 5, a strip-shaped thin plate material necessary for forming the light emitting element mounting side lead frame 5 is used. In addition to increasing the area, it is necessary to be careful because unnecessary parts are formed.

  The present invention is useful as a surface-mount semiconductor device that can be easily manufactured with a small number of steps while maintaining high heat dissipation.

The perspective view of the surface mounting type semiconductor device in an embodiment of the invention BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the surface mount type semiconductor device in embodiment of this invention, (a) is a top view, (b) is a bottom view, (c) is a left view, (d) is a right view. FIG. 3 is a development view of a lead frame of a surface mount semiconductor device in an embodiment of the present invention Perspective view of a conventional surface mount semiconductor device Sectional view of a conventional surface mount semiconductor device A perspective view of a lead frame of a conventional surface mount semiconductor device as seen from the lower surface side

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor light-emitting device 2 Light emitting element 3 Case 3a Recessed part 4 Lead frame 4a Gap 5 Light emitting element mounting side lead frame 5a Light emitting element mounting surface 5b Side surface part 5c Bottom surface part 6 Wire side lead frame 6a Wire bonding surface 6b Side surface part 6c Bottom surface part 7 Heat sink

Claims (2)

A semiconductor element is housed in a recess of the case and a lead frame that is conductively connected to the semiconductor element is protruded from the side surface of the case, and the protruding lead frame is further bent from the side surface along the bottom surface to the substrate. In the surface mounted semiconductor device to be mounted,
The lead frame bent along the side surface is provided with a further bent heat radiating plate from the bottom surface along at least one other side surface adjacent to the side surface, and the heat radiating plate is substantially the same as the other side surface. A surface-mount type semiconductor device formed over the entire surface. 2. The surface mount semiconductor device according to claim 1, wherein the semiconductor element is die-bonded to the lead frame.

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