JP2015195389A - Semiconductor device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a semiconductor device which allows at least a side surface of one of a die pad and a lead part to get wet with solder, and to provide a manufacturing method of the semiconductor device.SOLUTION: A semiconductor device 20 includes a lead frame 10 having a die pad 25 and a lead part 26, a semiconductor element 21 placed on the die pad 25 of the lead frame 10, and a bonding wire 22 electrically connecting the lead part 26 of the lead frame 10 with the semiconductor element 21. The lead frame 10, the semiconductor element 21, and the bonding wire 22 are sealed with a sealing resin part 24. The lead part 26 of the lead frame 10 has a bottom surface 28 that is exposed to the exterior and a side surface 29 which continues into the bottom surface 28 and is exposed to the exterior. A number of guide passages 43, which lead solder upwards, are formed on the side surface 29.

Description

  The present invention relates to a semiconductor device including a semiconductor element and a manufacturing method thereof.

  Conventionally, as a thin semiconductor device (semiconductor package), for example, a QFN (Quad Flat Non-leaded package) type or a SON (Small Outline Non-leaded Package) type is known. Among such thin semiconductor devices, there is a bottom-mount type semiconductor device, and the bottom-mount type semiconductor device has a bottom-mount type lead frame on which a semiconductor element is mounted.

  By the way, the conventional QFN type semiconductor device generally has a problem that it is difficult to sufficiently wet the metal surface exposed to the side of the semiconductor device with solder. For this reason, the metal exposed to the side of the semiconductor device for reasons such as increasing the mounting strength on the substrate, enabling visual confirmation of the mounting state of the semiconductor device, or facilitating repair of the semiconductor device. There is a need to ensure that the surface is sufficiently wetted with solder.

  For the exposed part of the lower surface of the part to be mounted on the board, there are a method of performing a surface treatment such as plating that wets the solder in advance from the frame stage, a method of performing a soldering treatment such as pre-solder plating before dividing into individual pieces, etc. . For the parts where the solder has been wetted, the parts will be wetted by the solder enough, but in any method, the section where the metal is cut by dicing or pressing after singulation is exposed because the part where the solder has not been wetted is exposed. There was a problem that the solder did not get wet enough.

  Patent Document 1 discloses a technique for increasing the bonding strength of solder to the terminal portion 5 by forming a groove 5 a on the back surface of the terminal portion 5 by half etching.

JP 2002-26222 A

  By the way, according to Japanese Patent Application Laid-Open No. 2004-228561, the above-described points, that is, increasing the mounting strength of the semiconductor device, making it possible to visually check the mounting state of the semiconductor device, or facilitating repair of the semiconductor device to some extent. Improvements are being made. However, in order to further improve these points, there is a demand for a structure in which the entire metal surface exposed to the side of the semiconductor device is wetted with solder.

  In particular, when an LED element is used as a semiconductor element, visual inspection is often performed in the mounting inspection process, and inspection is difficult if there is no solder on the side surface of the semiconductor device. Moreover, when using an LED element, it is often necessary to replace an LED element with a low light amount. For this reason, when solder exists on the side surface of the semiconductor device, it is considered that the LED element can be easily replaced.

  The present invention has been made in consideration of such points, and an object thereof is to provide a semiconductor device and a method for manufacturing the same that can wet at least one side surface of a die pad and a lead portion with solder.

  The present invention relates to a lead frame having a die pad and a lead part, a semiconductor element mounted on the die pad of the lead frame, a conductive part electrically connecting the lead part of the lead frame and the semiconductor element, and a lead frame , A semiconductor element, and a sealing resin portion that seals the conductive portion, and at least one of the die pad and the lead portion of the lead frame is exposed to the outside and is connected to the bottom surface and exposed to the outside. The semiconductor device is characterized in that a plurality of guide paths for guiding the solder upward are formed on at least one side surface of the die pad and the lead portion.

  The present invention is the semiconductor device characterized in that each guide path includes a vertical groove formed on a side surface.

  The present invention is the semiconductor device characterized in that each guide path includes an inclined groove formed on a side surface.

  The present invention is a semiconductor device characterized in that a recess opening on a side surface is provided on a bottom surface.

  The present invention is a semiconductor device characterized in that the side surface is composed of a pair of side surface portions separated from each other via a recess, and a plurality of guide paths are formed in each side surface portion.

  The present invention is a semiconductor device characterized in that it further includes an outer resin portion surrounding the semiconductor element and having a resin recess, and the sealing resin portion is filled in the resin recess of the outer resin portion.

  The present invention relates to a method of manufacturing a semiconductor device, a step of preparing a lead frame having a plurality of die pads and a plurality of lead portions, a step of placing a semiconductor element on each die pad of the lead frame, and each of the lead frames A step of connecting the lead portion and each semiconductor element with the conductive portion, a step of resin-sealing the lead frame, the semiconductor element, and the conductive portion with a sealing resin portion, and a step of cutting the lead frame for each semiconductor element. And at least one of the die pad and the lead portion of the lead frame has a bottom surface that is exposed to the outside and a side surface that is continuous with the bottom surface and is exposed to the outside, and each die pad in the step of cutting the lead frame And a plurality of guide paths for guiding the solder upward are formed on at least one side surface of each lead portion. That is a method of manufacturing a semiconductor device.

  According to the present invention, since many guide paths for guiding the solder upward are formed on the side surface of the lead frame that is exposed to the outside, it is easy to wet the side surface of the lead portion of the lead frame with the solder. It becomes.

1 is a perspective view showing a semiconductor device according to a first embodiment of the present invention. Sectional drawing which shows the semiconductor device by the 1st Embodiment of this invention (II-II sectional view taken on the line of FIG. 1). The side view which shows the semiconductor device by the 1st Embodiment of this invention (III direction arrow line view of FIG. 1). 1 is a bottom view showing a semiconductor device according to a first embodiment of the present invention (viewed in the direction of arrows IV in FIG. 1). The side view which shows the modification of the semiconductor device by the 1st Embodiment of this invention (the figure corresponding to FIG. 3). The figure which shows the manufacturing method of a lead frame. 1 is a plan view showing a lead frame used in a semiconductor device according to a first embodiment of the present invention. The figure which shows the manufacturing method of the semiconductor device by the 1st Embodiment of this invention. The figure which shows the process of cut | disconnecting a lead frame. Sectional drawing which shows the state by which the semiconductor device by the 1st Embodiment of this invention is mounted on the wiring board. The perspective view which shows the semiconductor device by the 2nd Embodiment of this invention. Sectional drawing which shows the semiconductor device by the 2nd Embodiment of this invention (XII-XII sectional view taken on the line of FIG. 11). The side view which shows the semiconductor device by the 2nd Embodiment of this invention (XIII direction arrow line view of FIG. 11). The bottom view which shows the semiconductor device by the 2nd Embodiment of this invention (XIV direction arrow line view of FIG. 11). FIG. 6 is a plan view showing a lead frame used in a semiconductor device according to a second embodiment of the present invention. The perspective view which shows the semiconductor device by the 3rd Embodiment of this invention. Sectional drawing which shows the semiconductor device by the 3rd Embodiment of this invention (XVII-XVII sectional view taken on the line of FIG. 16). The side view which shows the semiconductor device by the 3rd Embodiment of this invention (XVIII direction arrow line view of FIG. 16). The bottom view which shows the semiconductor device by the 3rd Embodiment of this invention (XIX direction arrow line view of FIG. 16). FIG. 6 is a plan view showing a lead frame used in a semiconductor device according to a third embodiment of the present invention. The perspective view which shows the semiconductor device by the 4th Embodiment of this invention. Sectional drawing which shows the semiconductor device by the 4th Embodiment of this invention (XXII-XXII sectional view taken on the line of FIG. 21). The side view which shows the semiconductor device by the 4th Embodiment of this invention (XXIII direction arrow line view of FIG. 21). The bottom view which shows the semiconductor device by the 4th Embodiment of this invention (XXIV direction arrow line view of FIG. 21). FIG. 6 is a plan view showing a lead frame used in a semiconductor device according to a fourth embodiment of the present invention.

First Embodiment Hereinafter, a first embodiment of the present invention will be described with reference to FIGS.

Configuration of Semiconductor Device First, a first embodiment of a semiconductor device according to the present invention will be described with reference to FIGS. 1 to 4 are views showing a semiconductor device according to a first embodiment of the present invention.

  As shown in FIGS. 1 to 4, the semiconductor device 20 includes a lead frame 10 having a die pad 25 and lead portions 26, 26, a semiconductor element 21 placed on the die pad 25 of the lead frame 10, and a lead frame. 10 and a semiconductor element 21 are provided with a pair of bonding wires (conductive portions) 22.

  An outer resin portion 23 having a resin recess 23 a is provided so as to surround the semiconductor element 21. The outer resin portion 23 is integrated with the lead frame 10. Further, the lead frame 10, the semiconductor element 21, and the bonding wire 22 are sealed with a light-transmitting sealing resin portion 24. The sealing resin portion 24 is filled in the resin recess 23 a of the outer resin portion 23. Hereinafter, the respective constituent members constituting such a semiconductor device 20 will be sequentially described.

  As the semiconductor element 21, various semiconductor elements generally used in the past can be used. In particular, an LED element can be preferably used. In this case, the semiconductor element 21 made of LED elements changes from ultraviolet light to infrared light by appropriately selecting a material made of a compound semiconductor single crystal such as GaP, GaAs, GaAlAs, GaAsP, AlInGaP, or InGaN as the light emitting layer. The light emission wavelength across can be selected. Hereinafter, a case where the semiconductor element 21 is formed of an LED element will be described as an example.

  The semiconductor element 21 has a pair of terminal portions 21a and 21a. The semiconductor element 21 is fixed on the die pad 25 (on the reflective plating layer 12) in the resin recess 23a of the outer resin portion 23 by solder or die bonding paste. When using a die bonding paste, it is possible to select a die bonding paste made of an epoxy resin or a silicone resin having light resistance.

  The lead frame 10 is formed on the surface of the main body 11 having a mounting surface 11 a on which the semiconductor element 21 is mounted, and functions as a reflective layer for reflecting light from the semiconductor element 21. And a plating layer 12.

  Of these, the main body 11 is made of a metal plate. Examples of the material of the metal plate constituting the main body 11 include copper, copper alloy, 42 alloy (Ni 41% Fe alloy), and the like. The thickness of the main body 11 is preferably 0.05 mm to 0.5 mm, although it depends on the configuration of the semiconductor device.

  The reflective plating layer 12 functions as a reflective layer for reflecting light from the semiconductor element 21 (LED element), and is located on the outermost surface side of the lead frame 10. The reflective plating layer 12 desirably has die bonding properties and wire bonding properties in addition to the reflection function, and is made of, for example, a silver plating layer and having a high visible light reflectance. preferable. The plating thickness of the reflective plating layer 12 is desirably 1 to 10 μm.

  In addition, the lead frame 10 includes a die pad 25 on which the semiconductor element 21 is placed and a pair of lead portions 26 and 26 that are separated from the die pad 25. The outer resin portion 23 is filled between the die pad 25 and the lead portions 26 and 26, and the die pad 25 and the lead portions 26 and 26 are electrically insulated from each other. The die pad 25 has a bottom surface 27 exposed to the outside of the semiconductor device 20. Each lead portion 26 has a bottom surface 28 exposed to the outside of the semiconductor device 20 and a side surface 29 continuous with the bottom surface 28 and exposed to the outside of the semiconductor device 20. The bottom surface 27 of the semiconductor device 20 and the bottom surface 28 of each lead portion 26 are located on the same plane.

  The bottom surface 28 is subjected to a surface treatment so that the solder gets wet (not shown). Examples of such surface treatment include silver plating and pre-solder plating. Since batch processing is possible, the same type of surface treatment as that of the reflective plating layer 12 such as silver plating is desirable.

  In the present embodiment, a large number of guide paths 43 are formed on the side surfaces 29 of the lead portions 26 to guide the solder attached to the bottom surface 28 upward when the semiconductor device 20 is mounted. 1 to 4, each guide path 43 includes a vertical groove 44 formed on a side surface 29 of the lead portion 26, and the vertical groove 44 extends from the lower end to the upper end of the side surface 29. In order to effectively guide the solder upward from the bottom surface 28 side, the width of each vertical groove 44 is set to 0.1 μm to 1 μm, and the depth of each vertical groove 44 is set to 0.1 μm to 3 μm. It is preferable that the pitch between the vertical grooves 44 be 0.5 μm to 20 μm.

  As shown in the modification of FIG. 5, each guide path 43 may include an inclined groove 45 formed on the side surface 29 of the lead portion 26. In this case, each inclined groove 45 preferably has an inclination angle of 10 ° or more with respect to the bottom surface 28. If the angle of the inclined groove 45 with respect to the bottom surface 28 is less than 10 °, the solder may not be sufficiently guided upward. In FIG. 5, the width of each inclined groove 45 is 0.1 μm to 1 μm, the depth of each inclined groove 45 is 0.1 μm to 3 μm, and the pitch between adjacent inclined grooves 45 is 0.5 μm to 20 μm. It is preferable to do. In FIG. 5, each inclined groove 45 is a straight line. However, the present invention is not limited to this, and each inclined groove 45 may be an arcuate curve.

  On the other hand, each bonding wire 22 is made of a material having good conductivity such as gold, and one end thereof is connected to the terminal portion 21a of the semiconductor element 21 and the other end thereof is connected to the lead portion 26 of the lead frame 10. ing.

  The outer resin portion 23 is formed by, for example, injection molding or transfer molding of a thermoplastic resin or a thermosetting resin on the lead frame 10. The shape of the outer resin portion 23 can be variously realized by designing a mold used for injection molding or transfer molding. For example, the overall shape of the outer resin portion 23 may be a rectangular parallelepiped as shown in FIGS. 1 to 4, or may be a cylindrical shape or a conical shape. The bottom surface of the resin recess 23a can be rectangular, circular, elliptical, polygonal, or the like. The cross-sectional shape of the side wall of the resin recess 23a may be constituted by a straight line as shown in FIG. 2, or may be constituted by a curve.

  Regarding the thermoplastic resin or thermosetting resin used for the outer resin portion 23, it is particularly preferable to select a resin having excellent heat resistance, weather resistance and mechanical strength. As the kind of the thermoplastic resin, polyamide, polyphthalamide, polyphenylene sulfide, liquid crystal polymer, polyether sulfone, silicone, epoxy, polyurethane, polyetherimide, polybutylene terephthalate, and the like can be used. Furthermore, by adding any one of titanium dioxide, zirconium dioxide, potassium titanate, aluminum nitride and boron nitride as a light reflecting agent in these resins, the semiconductor element 21 is formed on the bottom and side surfaces of the resin recess 23a. The reflectance of light from the (LED element) can be increased, and the light extraction efficiency of the entire semiconductor device 20 can be increased.

  As the sealing resin portion 24, it is desirable to select a material having a high light transmittance and a high refractive index at the emission wavelength of the semiconductor element 21 in order to improve the light extraction efficiency. Therefore, it is possible to select an epoxy resin or a silicone resin as a resin that satisfies the characteristics of high heat resistance, weather resistance, and mechanical strength. In particular, when a high-brightness LED is used as the semiconductor element 21, the sealing resin portion 24 is preferably made of a silicone resin having high weather resistance because the sealing resin portion 24 is exposed to strong light.

Method for Manufacturing Lead Frame Next, a method for manufacturing the lead frame 10 used in the semiconductor device 20 shown in FIGS. 1 to 4 will be described with reference to FIGS.

  First, as shown in FIG. 6A, a main body 11 made of a metal substrate is prepared. As the main body 11, a metal substrate made of copper, copper alloy, 42 alloy (Ni 41% Fe alloy) or the like can be used as described above. In addition, it is preferable to use what the main-body part 11 performed the degreasing | defatting etc. on both surfaces, and performed the washing process.

  Next, a photosensitive resist is applied to the front and back surfaces of the main body 11 and dried, exposed through a desired photomask, and then developed to form etching resist layers 32 and 33 (FIG. 6B). ). In addition, a conventionally well-known thing can be used as a photosensitive resist.

  Next, the etching resist layers 32 and 33 are used as an anticorrosion film, and the main body 11 is etched with an etching solution (FIG. 6C). The corrosive liquid can be appropriately selected according to the material of the main body 11 to be used. For example, when copper is used as the main body 11, an aqueous ferric chloride solution is usually used and sprayed from both surfaces of the main body 11. It can be performed by etching.

  Next, the etching resist layers 32 and 33 are peeled and removed. In this way, the die pad 25 and the pair of lead portions 26 and 26 separated from the die pad 25 are obtained (FIG. 6D).

  Next, by performing electroplating, a metal is deposited on the main body 11 and a metal (for example, silver) is deposited on the main body 11 to form a reflective plating layer 12 made of, for example, a silver plating layer. In this case, a silver plating solution mainly composed of silver cyanide and potassium cyanide can be used as the plating solution for electrolytic plating for forming the reflective plating layer 12. Thus, the lead frame 10 used for the semiconductor device 20 can be obtained (FIG. 6E). At this time, it is desirable to simultaneously perform the processing of the bottom surface 28 in order to shorten the process. The metal plating layer constituting the reflective plating layer 12 is not limited to partial plating, and may be full plating.

  The lead frame 10 obtained in this way is composed of a multi-faced lead frame having a plurality of die pads 25 and a plurality of lead portions 26, as shown in FIG. In FIG. 7, a plurality of die pads 25 and a plurality of lead portions 26 are connected to each other via tie bars 16. In FIG. 7, the hatched portion indicates the reflective plating layer 12, and the alternate long and two short dashes line indicates a region corresponding to one semiconductor device 20.

Manufacturing Method of Semiconductor Device Next, a manufacturing method of the semiconductor device 20 shown in FIGS. 1 to 4 will be described with reference to FIGS. 8 (a)-(g) and FIGS. 9 (a)-(b).

  First, the lead frame 10 (multi-face lead frame) (see FIG. 7) having a plurality of die pads 25 and a plurality of lead portions 26 is manufactured by the above-described steps (FIGS. 6A to 6E) (see FIG. 7). 8 (a)).

  Next, the outer resin portion 23 is formed by injection molding or transfer molding of a thermosetting resin to the lead frame 10 (FIG. 8B). Thereby, the outer side resin part 23 and the lead frame 10 are integrally formed. At this time, by appropriately designing a mold used for injection molding or transfer molding, a resin recess 23a is formed in the outer resin portion 23, and the reflective plating layer 12 is outward (upward) in the resin recess 23a. ) To be exposed.

  Next, the semiconductor element 21 is mounted on the mounting surface 11 a (on the reflective plating layer 12) of the main body 11 of the lead frame 10. In this case, the semiconductor element 21 is mounted and fixed on the mounting surface 11a (on the reflective plating layer 12) of the main body 11 using a solder or a die bonding paste (die attach step) (FIG. 8 (c). )).

  Next, each terminal part 21a of the semiconductor element 21 and each lead part 26 of the main body part 11 are electrically connected to each other by a bonding wire 22 (wire bonding process) (FIG. 8D).

  Thereafter, the sealing resin portion 24 is filled in the resin concave portion 23a of the outer resin portion 23, and the lead frame 10, the semiconductor element 21, and the bonding wire 22 are sealed by the sealing resin portion 24 (FIG. 8E). .

  Next, the outer resin portion 23 between the semiconductor elements 21 is diced to separate the lead frame 10 for each semiconductor element 21 (FIG. 8F). At this time, the lead frame 10 is first placed and fixed on the dicing tape 37, and then, for example, while rotating a blade 38 made of, for example, a diamond grindstone, a direction perpendicular to the paper surface of FIG. 7 in the direction of arrow L), the outer resin portion 23 between the semiconductor elements 21 is cut.

  At this time, each lead portion 26 of the lead frame 10 is formed with a side surface 29 that continues to the bottom surface 28 and is exposed to the outside. A large number of guide paths 43 are formed on the side surfaces 29 of the lead portions 26 to guide the solder upward. That is, the abrasive grains of the blade 38 cause polishing scratches on the cut surface (side surface 29) of the lead portion 26, and the polishing scratches constitute a number of guide paths 43.

  When cutting the lead frame 10, as shown in FIG. 9A, by bringing the height position of the lead frame 10 near the center of the blade 38, the polishing scratches by the blade 38 become substantially vertical, A guide path 43 (see FIG. 3) composed of the longitudinal grooves 44 can be formed. On the other hand, as shown in FIG. 9B, when the height position of the lead frame 10 is separated from the rotation center of the blade 38, the polishing scratches by the blade 38 become oblique, and the guide path 43 (see FIG. 5) can be formed.

  The width, depth, and pitch of the vertical groove 44 or the inclined groove 45 can be controlled by appropriately setting the particle size of the abrasive grains of the blade 38.

  In this way, the semiconductor device 20 shown in FIGS. 1 to 4 can be obtained (FIG. 8G).

Operation and Effect of the Present Embodiment Next , the operation of the present embodiment having such a configuration will be described with reference to FIG. FIG. 10 is a cross-sectional view showing a state where the semiconductor device is mounted on a wiring board.

  As shown in FIG. 10, the semiconductor device 20 according to the present embodiment is arranged and mounted on a wiring board 51. Such a wiring substrate 51 includes a substrate body 52 and a pair of wiring terminal portions 53 and 53 formed on the substrate body 52. Among these, each wiring terminal portion 53 is connected to the bottom surface 28 of the corresponding lead portion 26 via a connection solder portion 54.

  As described above, when the semiconductor device 20 is mounted on the wiring board 51 using the connection solder portion 54, the molten solder (connection solder portion 54) is attached to the bottom surface 28 of each lead portion 26. At this time, the melted solder travels along the many guide paths 43 (vertical grooves 44) from the bottom surface 28 by the capillary phenomenon, and ascends the side surface 29. Thereafter, the raised solder is cooled and solidified on the side surface 29, and the side surface 29 is entirely covered with the solder.

  As described above, according to the present embodiment, since many guide paths 43 for guiding the solder upward are formed on the side surface 29 of the lead portion 26, the side surface 29 exposed to the outside of the lead portion 26 can be easily formed. Can be covered with solder. Thereby, compared with the case where the solder has adhered only to the bottom face 28, the intensity | strength which mounts the semiconductor device 20 in the wiring board 51 can be improved, and the mounting reliability of the semiconductor device 20 improves.

  Further, according to the present embodiment, it is possible to easily visually check whether or not the semiconductor device 20 is mounted on the wiring board 51, so that the mounting inspection can be easily performed.

  Further, according to the present embodiment, when it is necessary to remove the semiconductor device 20 from the wiring substrate 51, the connection solder portion 54 is melted by heating the side surface 29, and the wiring terminal portion 53 and the bottom surface 28 are separated. Therefore, the semiconductor device 20 can be easily replaced.

  Furthermore, according to the present embodiment, since a large number of guide paths 43 are formed on the side surface 29 at the same time when the lead frame 10 is cut, there is no need to provide a separate process for forming the guide paths 43, and the manufacturing cost is reduced. Will not rise.

Second Embodiment Next, a second embodiment of the present invention will be described with reference to FIGS. 11 to 15 are views showing a second embodiment of the present invention. The second embodiment shown in FIGS. 11 to 15 is different from the first embodiment in that the bottom surface 28 of the lead portion 26 is provided with a recess 61 that opens to the side surface 29. Other configurations are the same as those of the first embodiment described above. This is the same as the embodiment. 11 to 15, the same parts as those of the first embodiment shown in FIGS. 1 to 10 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the semiconductor device 20 </ b> A shown in FIGS. 11 to 14, a rectangular parallelepiped recess 61 is provided on the bottom surface 28 of the lead portion 26. The recess 61 opens to the bottom surface 28 and the side surface 29, but does not open to the die pad 25 side. This prevents the outer resin portion 23 from entering the recess 61 when the outer resin portion 23 is formed (see FIG. 8B). Note that the shape of the concave portion 61 viewed from the side surface may be a semicircular shape, a semielliptical shape, or a polygonal shape in addition to a rectangle as shown in FIG.

  Also in this embodiment, an inclined groove 45 as shown in FIG. 5 may be used as the guide path 43 instead of the vertical groove 44.

  The manufacturing method of such a semiconductor device 20A is substantially the same as the steps shown in FIGS. 6 (a)-(e) and FIGS. 8 (a)-(g). In this case, the lead frame shown in FIG. 15 is used. The lead frame 10 shown in FIG. 15 includes a multi-faced lead frame having a plurality of die pads 25 and a plurality of lead portions 26, and a half-etched portion 62 corresponding to the recess 61 is formed at the center of each lead portion 26. Is formed. The half-etched portion 62 is formed thinner than the entire thickness of the lead frame 10 and is simultaneously formed when etching the main body portion 11 (see FIG. 6C).

  According to the present embodiment, the following operational effects can be obtained in addition to the operational effects of the first embodiment shown in FIGS. That is, by providing the bottom surface 28 of the lead portion 26 with the concave portion 61 that opens to the side surface 29, when the semiconductor device 20 </ b> A is mounted on the wiring substrate 51, molten solder (connection solder portion 54) flows into the concave portion 61. To do. In this case, since the solder (connection solder portion 54) is solidified in the recess 61, the wiring terminal portion 53 and the bottom surface 28 of the lead portion 26 are more firmly fixed, and the mounting strength of the semiconductor device 20A can be further improved. it can. Further, since the solder on the bottom surface 28 can escape into the recess 61, the thickness of the connecting solder portion 54 on the bottom surface 28 becomes uniform, and the semiconductor device 20A can be easily attached to the wiring substrate 51 horizontally.

Third Embodiment Next, a third embodiment of the present invention will be described with reference to FIGS. 16 to 20 are diagrams showing a third embodiment of the present invention. The third embodiment shown in FIGS. 16 to 20 is different in that the semiconductor device 20B has one die pad 25 and one lead portion 26, and the other configuration is the first embodiment described above. This is substantially the same as the embodiment. 16 to 20, the same parts as those of the first embodiment shown in FIGS. 1 to 10 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the semiconductor device 20B shown in FIGS. 16 to 19, the semiconductor device 20B includes a die pad 25 and one lead portion 26 that is separated from the die pad 25. In this case, the semiconductor element 21 has one terminal portion 21 a, and this terminal portion 21 a is connected to the lead portion 26 via the bonding wire 22. Furthermore, the semiconductor element 21 is also electrically connected to the die pad 25 by solder (not shown).

  In the present embodiment, the die pad 25 has a bottom surface 27 exposed to the outside of the semiconductor device 20B, and a side surface 19 connected to the bottom surface 27 and exposed to the outside of the semiconductor device 20B. In addition to the side surfaces 29 of the lead portions 26, many guide paths 43 that guide the solder upward are also formed on the side surfaces 19 of the die pad 25.

  Also in this embodiment, an inclined groove 45 as shown in FIG. 5 may be used as the guide path 43 instead of the vertical groove 44. In the present embodiment, as in the embodiment shown in FIGS. 11 to 14, the bottom surface 28 of the lead portion 26 and the bottom surface 27 of the die pad 25 are provided with recesses 61 and 61 that open to the side surfaces 29 and 19, respectively. May be.

  The manufacturing method of the semiconductor device 20B is substantially the same as the steps shown in FIGS. 6 (a)-(e) and FIGS. 8 (a)-(g). In this case, the lead frame shown in FIG. 20 is used. The lead frame 10 shown in FIG. 20 is composed of a multi-faced lead frame having a plurality of die pads 25 and a plurality of lead portions 26, and is adjacent to the lead portion 26 corresponding to one semiconductor device 20B and the semiconductor device 20B. A die pad 25 corresponding to the semiconductor device 20B is integrally formed.

  According to the present embodiment, in addition to the operational effects of the first embodiment shown in FIGS. 1 to 10, the semiconductor device 20B has one die pad 25 and one lead portion 26, so that the semiconductor device The overall shape of 20B can be reduced in size.

Fourth Embodiment Next, a fourth embodiment of the present invention will be described with reference to FIGS. 21 to 25 are diagrams showing a fourth embodiment of the present invention. In the fourth embodiment shown in FIGS. 21 to 25, the side surface 29 of the lead portion 26 is composed of a pair of side surface portions 29a and 29a separated from each other via a recess 66 therebetween, and bonding to the semiconductor element 21 is performed. The point that the wire 22 is sealed only by the sealing resin portion 24 is different, and the other configuration is substantially the same as that of the above-described first embodiment. 21 to 25, the same parts as those of the first embodiment shown in FIGS. 1 to 10 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the semiconductor device 20C shown in FIGS. 21 to 24, the side surface 29 of the lead portion 26 is composed of a pair of side surface portions 29a and 29a separated from each other through a recess 66 therebetween. A large number of guide paths 43 are formed in each of the side surface portions 29a and 29a. In this case, the recess 66 formed in each lead portion 26 penetrates the lead portion 26 in the thickness direction. The recess 66 opens to the side surface 29, but does not open to the die pad 25 side.

  In the present embodiment, the semiconductor element 21 and the bonding wire 22 are collectively sealed only by the sealing resin portion 24 without using the outer resin portion 23. The sealing resin portion 24 is filled between the die pad 25 and each lead portion 26, but the sealing resin portion 24 is not filled in the recess 66. In addition, a portion of each lead portion 26 around the recess 66 is exposed outward from the sealing resin portion 24.

  Also in this embodiment, an inclined groove 45 as shown in FIG. 5 may be used as the guide path 43 instead of the vertical groove 44.

  The manufacturing method of the semiconductor device 20C is substantially the same as the steps shown in FIGS. 6A to 6E and FIGS. 8A to 8G except for the step of forming the outer resin portion 23 (FIG. 8B). It is the same. In this case, the lead frame shown in FIG. 25 is used. The lead frame 10 shown in FIG. 25 is composed of a multifaceted lead frame having a plurality of die pads 25 and a plurality of lead portions 26, and a through hole 67 corresponding to the recess 66 is formed at the center of each lead portion 26. Has been.

  According to the present embodiment, the following operational effects can be obtained in addition to the operational effects of the first embodiment shown in FIGS. That is, in the present embodiment, by providing the recess 66, when the semiconductor device 20C is mounted on the wiring board 51, the molten solder flows into the recess 66, so that the mounting strength of the semiconductor device 20C is further improved. Can be made. Further, since the solder on the bottom surface 28 of the lead portion 26 can escape into the recess 66, the thickness of the solder on the bottom surface 28 becomes uniform, and the semiconductor device 20C can be mounted horizontally.

DESCRIPTION OF SYMBOLS 10 Lead frame 11 Main-body part 12 Reflective plating layer 19 Side surface 20, 20A-20D Semiconductor device 21 Semiconductor element 22 Bonding wire (conductive part)
23 Outer resin portion 24 Sealing resin portion 25 Die pad 26 Lead portion 27 Bottom surface of die pad 28 Bottom surface of lead portion 29 Side surface of lead portion 29a Side surface portion 43 Guide path 44 Vertical groove 45 Inclined groove

Claims (7)

A lead frame having a die pad and a lead portion;
A semiconductor element mounted on a die pad of a lead frame;
A conductive portion that electrically connects the lead portion of the lead frame and the semiconductor element;
A lead frame, a semiconductor element, and a sealing resin portion for sealing the conductive portion;
At least one of the die pad and the lead part of the lead frame has a bottom surface that is exposed to the outside, and a side surface that is continuous with the bottom surface and is exposed to the outside.
A semiconductor device, wherein a plurality of guide paths for guiding solder upward are formed on at least one side surface of the die pad and the lead portion.   2. The semiconductor device according to claim 1, wherein each guide path includes a vertical groove formed on a side surface.   2. The semiconductor device according to claim 1, wherein each guide path includes an inclined groove formed on a side surface.   4. The semiconductor device according to claim 1, wherein the bottom surface is provided with a recess opening in the side surface. 5.   5. The semiconductor device according to claim 4, wherein the side surface includes a pair of side surface portions separated from each other via a recess therebetween, and a plurality of guide paths are formed in each side surface portion.   The outer resin part surrounding the semiconductor element and having a resin recess is further provided, and the sealing resin part is filled in the resin recess of the outer resin part. The semiconductor device described. In a method for manufacturing a semiconductor device,
Preparing a lead frame having a plurality of die pads and a plurality of lead portions;
Placing a semiconductor element on each die pad of the lead frame;
Connecting each lead portion of the lead frame and each semiconductor element by a conductive portion;
A step of resin-sealing the lead frame, the semiconductor element, and the conductive portion with a sealing resin portion; and a step of cutting the lead frame for each semiconductor element,
At least one of the die pad and the lead part of the lead frame has a bottom surface that is exposed to the outside, and a side surface that is continuous with the bottom surface and is exposed to the outside.
A method of manufacturing a semiconductor device, wherein in the step of cutting the lead frame, a plurality of guide paths for guiding the solder upward are formed on at least one side surface of each die pad and each lead portion.

Images