JP4895493B2 - Resin-sealed light emitting device - Google Patents

Description

  The present invention relates to a resin-sealed light emitting device, and more particularly, to a light emitting device having a package covered with a translucent resin in a state where a light emitting element is mounted on a lead frame and a conductive wire is bonded to a lead member. The present invention relates to the structure of lead members and packages, and is used for illumination light sources, various indicator light sources, in-vehicle light sources, display light sources, liquid crystal backlight light sources, and the like.

  Light emitting diodes that use light emitting diode (LED) chips as light emitting elements are used in a wide range of fields such as light sources for mobile phone indicators and liquid crystal backlights because they are small, consume less power and have a long service life. Yes.

  There are various structures as a package for mounting an LED chip. Here, a resin-sealed light emitting device having a full mold package structure will be described as an example.

  FIG. 4 shows a conventional example of a resin-sealed light emitting device (for example, FIG. 11 of Patent Document 1). In this light emitting device, the light emitting chip 2 is mounted on the tip of the inner lead portion of one lead 3a of the pair of leads 3a and 3b by die bonding, and the inner lead portion of the other lead 3b and the light emitting chip 2 are mounted. Are electrically connected by bonding of the conductive wire 4, and then the light emitting chip 2, the inner lead portions of the leads 3 a and 3 b, and the entire conductive wire 4 are sealed with the transparent resin 5 and the light emitting chip 2 is It is molded so as to form a light emitting surface 6 having a convex lens shape on the side.

  As another conventional example for electrically connecting the light emitting chip 2, a pair of electrodes (p electrode and n electrode) on the light emitting chip are bonded and connected to the inner lead portions of the pair of leads with conductive wires, respectively. There are also things.

  By the way, when the adhesive strength between the pair of leads 3a and 3b and the translucent resin 5 is low at the time of transfer molding of the translucent resin 5, the surface of the package resin made of the translucent resin becomes hygroscopic. When passing through a reflow furnace during mounting, the moisture in the package resin becomes vapor and cracks are generated in the package resin, and there is a problem that the reliability thereafter is remarkably lowered. In addition, there is a problem that the conductive wire 4 is disconnected due to the shear stress during the temperature cycle. Further, in a resin-sealed light emitting device in which the light emitting chip 2 on the lead and the inner lead portion of the lead are electrically connected by the conductive wire 4, a connecting portion (second bond) between the inner lead portion and the conductive wire 4 is used. It is known that the connection strength of (part) is weak (see Patent Document 1).

  In Patent Document 2, in a semiconductor device having a large number of lead portions around a die pad portion of a lead frame, a ring-shaped groove is formed along the outer periphery of the die pad of the lead frame. It is disclosed that the shear stress during the temperature cycle is relaxed to prevent disconnection of the conductive wire, the adhesion between the lead frame and the package resin is improved, and the prevention of peeling is easily realized. .

  However, the lead frame for a light-emitting device described above with reference to Patent Document 1 has a pair of lead portions corresponding to the p-electrode and the n-electrode. Unlike a lead frame of a semiconductor device having a large number of lead portions, it is difficult to say that it is best to employ a structure in which ring-shaped grooves are processed along the outer periphery of the die pad. That is, as a lead frame for a light emitting device, an appropriate structure for improving the adhesion strength between the lead frame and the translucent resin and preventing disconnection of the conductive wire due to shear stress during the temperature cycle is required. ing.

  Further, in Patent Document 3, when the resin is poured along the upper and lower surfaces of the island portion of the lead frame on which the semiconductor chip is placed and full molding is performed, the upper surface of the island portion is improved. The point that the mountain-shaped protrusions are integrally formed by press working is disclosed. At this time, a groove is formed on the lower surface of the island portion corresponding to the protrusion.

  In Patent Document 4, a silicon resin layer is applied and formed on the island portion of the lead frame so as to cover the surface of the semiconductor element, and the sealing resin layer is covered on the semiconductor element and the lead frame portion including the silicon resin layer. In the formed semiconductor device, in order to prevent the low viscosity silicon resin from flowing out, it is disclosed that a groove for preventing silicon resin from flowing out is formed in a lead frame portion corresponding to the peripheral portion of the silicon resin layer. .

The light emitted from the LED chip is limited monochromatic light such as red, green, and blue, and a fluorescent material for converting it to a different wavelength may be used in combination with a light emitting element. . In this case, a light-emitting device that emits white light by adding and mixing light emitted directly from the LED chip, light emitted from the LED chip, and wavelength-converted light emitted from the fluorescent material is known. ing. Patent Document 5 discloses that a light-transmitting coating material or a light-transmitting coating layer mixed with a wavelength converting fluorescent material is attached to or coated on the surface of an LED device having a shell-shaped shape. Or the material of a coating layer, the fluorescent substance contained in it, etc. are disclosed.
JP 2002-198570 A JP-A-5-95077 Japanese Patent Laid-Open No. 5-218264 JP-A-8-293626 Japanese Patent Laid-Open No. 11-87784

  The inventor of the present application analyzed the cause of electrical contact failure or disconnection of the conductive wire in the conventional resin-encapsulated light emitting device, and found that the electrical conductivity connected to the electrode (for example, p electrode) on one side of the LED chip. We have determined that defects are likely to occur in the second bond portion of the wire. As a result of investigating the cause, among the pair of lead portions of the lead frame, the lead portion connected to the p-electrode of the LED chip is shorter than the lead portion (having the die pad portion) connected to the n-electrode, Since the surface area is small, the adhesion strength with the light-transmitting resin (epoxy resin) for the package is low. For this reason, when passing through the reflow furnace of 220 degreeC or more at the time of surface mounting of a light-emitting device, for example, it turned out that the conductive wire connected to the p electrode is strongly pulled by the epoxy resin with a large thermal expansion.

  The present invention has been made by intensive studies in view of the above circumstances, and its purpose is to further improve the adhesion strength between the lead member and the resin package, and to improve conductivity due to stress during temperature cycling. Realized an appropriate structure to prevent electrical contact failure or disconnection of the second bond part of the wire as much as possible, and achieved high reliability and yield improvement for thermal shock tests, and mounted a large area, high output LED chip. The object is to provide a resin-sealed light emitting device.

  The resin-sealed light emitting device according to the present invention uses a metal member, and one end portion in the length direction is a die pad portion, and an intermediate portion in the length direction is a first inner lead portion. The other end in the length direction is a first lead member in which the other end portion in the direction becomes a first outer lead portion and a metal member, and one end portion in the length direction becomes the second inner lead portion, and the other end in the length direction. The first lead member has a second lead member facing each other with a predetermined gap, and a pair of electrodes, and the first lead member has a pair of electrodes. A light-emitting element mounted and fixed on the die pad portion of the lead member, and between one electrode of the pair of electrodes of the light-emitting element and the second inner lead portion of the second lead member Conductive wire with both ends bonded for electrical connection And the light emitting element, the die pad portion of the first lead member, the first inner lead portion of the first lead member, the second inner lead portion of the second lead member, and the conductive wire. In this way, the resin-encapsulated light-emitting device has a resin package formed by transfer molding a translucent resin, and the second lead member is formed in the vertical direction on both side surfaces of the second inner lead portion. At least one first groove is formed, and at least one second groove is formed in the width direction of the bottom surface of the second inner lead portion, and the resin package is formed inside each of the grooves. Is partially embedded.

  One specific example of the first lead member is a die pad portion having a thick flat plate at one end in the length direction and a cup-shaped recess on the upper surface, and an intermediate portion in the length direction being the die. -A thick flat plate connected to the pad portion and serving as a first inner lead portion, and the other end portion in the length direction serving as the first outer lead portion, and on the bottom surface of the concave portion of the die pad portion. A light emitting element is mounted. Also, one specific example of the second lead member is such that one end portion in the length direction is a thick flat plate shape and serves as the second inner lead portion, and the other end portion in the length direction is the second end portion. It is a flat plate shape thinner than the inner lead part and becomes the second outer lead part,

According to the resin-sealed light emitting device of claim 1, the second lead member is shorter and has a smaller surface area than the first lead member having the die pad portion, and the second inner lead portion has a length. One end portion in the direction is a thick flat plate shape, the other end side in the length direction of the thick portion is a flat plate shape thinner than the thick portion, and on the thick portion of the second inner lead portion A conductive wire is bonded to each other, and is opposed to sandwich the second bond portion in the vertical direction on both side surfaces of the second bond portion that is a connection portion between the second inner lead portion and the conductive wire. At least one first groove is formed, and a second groove is formed in the width direction of the bottom surface of the second bond portion, and a part of the resin package is embedded in each of these grooves. It is.
Therefore, even when the second lead member is shorter than the first lead member and has a small surface area, the surface area of the second inner lead portion of the second lead member is larger due to the presence of a thick flat plate. Therefore, the adhesion strength between the second lead member and the resin package is further improved. Further, grooves are formed on both side surfaces and the bottom surface of the second bond portion of the second inner lead portion, and a part of the resin package is embedded in each of these grooves, so that the second lead member The adhesion strength between the resin package and the resin package is further improved. As a result, for example, electrical contact failure or disconnection of the second bond portion of the second conductive wire due to shear stress during temperature cycling when passing through a reflow furnace during surface mounting is prevented, and reliability and yield are improved. Large area, high output LED chips can be mounted.

According to the resin-sealed light emitting device of claim 2, the surface area of the die pad portion and the first inner lead portion of the first lead member is large, and the adhesion strength between the first lead member and the resin package is further increased. improves.

  According to the resin-sealed light emitting device of claim 3, the slit-like second groove exists on the bottom surface of the second inner lead portion, and the second lead member and the translucent resin for the package are provided. The adhesion strength of is improved.

  According to the resin-sealed light emitting device of the fourth aspect, the third groove having a narrow width exists on the bottom surface of the first inner lead portion of the first lead member, and the first lead member and the resin package Since the adhesion strength is further improved, it is possible to prevent poor electrical contact or disconnection of the second bond portion of the first conductive wire, and to improve reliability and yield.

  According to the resin-sealed light-emitting device of claim 5, since the external terminal for surface mounting connection is provided on the bottom surface side of the resin package, the area when the surface mounting is performed on the substrate of the application device can be reduced, and the mounting area It becomes possible to improve the efficiency and downsize the application device.

  Hereinafter, embodiments and examples of the resin-sealed light-emitting device of the present invention will be described, but the present invention is not limited to these embodiments and examples.

<First Embodiment>
FIG. 1 is a partial cross-sectional side view schematically showing an example according to the first embodiment of the resin-sealed light emitting device of the present invention. FIGS. 2A and 2B are a top view and a side view, respectively, showing the lead member in FIG.

  The light emitting device shown in FIG. 1 includes, as main components, an LED chip 10, a first lead member 11 and a second lead member 12 each using the same metal member, conductive wires 13 and 14, and a resin. Package 15.

  The first lead member 11 has a flat plate shape with one end portion and an intermediate portion in the length direction being thick, with one end portion serving as a die pad portion 110 and the intermediate portion serving as a first inner lead portion 111. The other end is a thin flat plate and serves as the first outer lead 112. The die pad portion 110 has a central portion on the upper surface that is recessed in a cup shape or a dish shape, and an inner side surface that is a light reflecting mirror. 2A and 2B, reference numeral 110a denotes a recessed portion on the upper surface of the die pad portion 110.

  The second lead member 12 has one end portion in the length direction which is a flat plate having the same thickness as the thick portion of the first lead member 11 and becomes the second inner lead portion 121, and the other end portion in the length direction. Is a thin flat plate shape and serves as the second outer lead portion 122. The second lead member 12 is shorter than the first lead member 11 by a length corresponding to the die pad portion 110 and has a small surface area.

  The LED chip 10 has a pair of electrodes (p electrode and n electrode) corresponding to the anode and the cathode on the upper surface side, and is mounted on the central portion of the die pad portion 110 of the first lead member 11 and fixed ( Die bonding). Of the pair of electrodes of the LED chip 10, the first electrode (n electrode in this example) is electrically connected to the first lead member 11. In this example, both ends of the first conductive wire 13 are bonded and connected so as to electrically connect the n electrode and the first inner lead portion 111 of the first lead member 11. Then, both ends of the second conductive wire 14 are connected so as to electrically connect the second electrode (p electrode in this example) and the second inner lead portion 121 of the second lead member 12. Bonded connection.

  The LED chip 10, the die pad portion 110 and the first inner lead portion 111 of the first lead member 11, the second inner lead portion 121 of the second lead member 12, the first conductive wire 13, A resin package 15 is formed by transfer molding of a translucent resin so as to cover the second conductive wire 14. In this case, the resin package 15 includes the die pad portion 110 and the first inner lead portion 111 of the first lead member 11, the second inner lead portion 121 of the second lead member 12, and the first conductive wire. 13. A portion covering the second conductive wire 14 is, for example, a rectangular parallelepiped. The light emitting surface 151 having a convex lens shape is molded on the upper surface side (above the LED chip 10) of the rectangular parallelepiped portion. However, the overall shape of the resin package 15 can be variously modified.

  In the present embodiment, the second lead member 12 is formed with one wide first groove 123 in the vertical direction on both side surfaces of the second inner lead portion 121, so that the second inner lead At least one (preferably a plurality of) slit-like second grooves 124 having a width smaller than that of the first groove 123 are formed in the width direction of the bottom surface of the portion 121, and the inside of each of these grooves 123, 124 is formed. A part of the resin package 15 is embedded.

  The first lead member 11 is formed with at least one (preferably a plurality of) slit-like third grooves 113 in the width direction of the bottom surface of the first inner lead portion 111. A part of the resin package 15 is embedded in the inside. The third groove 113 has the same width and depth as the second groove 124 in this example. In order to further improve the adhesion strength between the first lead member 11 and the resin package 15, at least one slit-like shape is also formed in the width direction of the bottom surface of the die pad portion 110 of the first lead member 11. A third groove may be formed.

  The first lead member 11 and the second lead member 12 have outer lead portions 112 and 122 that protrude from the resin package 15 along the side surface of the resin package 15 and further have their tip portions on the bottom surface side of the resin package 15. The external terminal 16 for surface mounting connection is formed by bending and is connected during surface mounting.

  In the resin-sealed light emitting device having the above-described configuration, the second lead member 12 is formed with one wide first groove 123 in the vertical direction on both side surfaces of the second inner lead portion 121, so that the second A plurality of slit-like second grooves 124 each having a width smaller than that of the first groove 123 are formed in the width direction of the bottom surface of the inner lead portion 121, and the resin package 15 is formed inside each of these grooves 123, 124. Since the portion is embedded, the adhesion strength with the resin package 15 is improved even if the surface area of the adhesion portion with the resin package 15 is small.

  Further, in the first lead member 11, the die pad portion 110 and the first inner lead portion 111 have a large surface area, and a slit-like third groove is formed in the width direction of the bottom surface of the first inner lead portion 111. 113 is formed, and a part of the resin package 15 is embedded in the groove 113, so that the first lead member 11 also has improved adhesion strength with the resin package 15.

  When the resin-sealed light emitting device having the above configuration is surface-mounted on a substrate using, for example, a solder reflow method, soldering is performed by passing through a reflow furnace. At this time, the temperature at the time of the main heating after the preheating becomes a high temperature of about 220 ° C. to 240 ° C. above the melting point of the solder (about 260 ° C. or more in the case of lead-free). The second conductive wire 14 connected to the electrode tends to be pulled strongly, and the first conductive wire 13 connected to the n electrode is also pulled.

  In this case, the second lead member 12 is also pulled in the same direction by the thermal expansion of the epoxy resin, like the second conductive wire 14. As a result, the thermal stress applied to the second conductive wire 14 and its second bond portion is relieved, and no tensile force is applied only to the second bond portion of the second conductive wire 14. It is possible to prevent electrical contact failure or disconnection of the second bond portion as much as possible, and the failure rate is reduced.

  Similarly, the first lead member 11 is also pulled in the same direction by the thermal expansion of the epoxy resin, like the first conductive wire 13. Thereby, the thermal stress on the first conductive wire 13 and its second bond portion is relieved, and no tensile force is applied only to the second bond portion of the first conductive wire 13. It is possible to prevent electrical contact failure or disconnection of the second bond portion as much as possible, and the failure rate is reduced.

  As a result, according to the resin-sealed light-emitting device, it is possible to improve the reliability and yield of the thermal shock test, and to mount a large-area, high-power LED chip.

  In addition, since the external terminal 16 for surface mounting connection is provided on the bottom side of the resin package 15, the area required for surface mounting on the substrate of the application device can be reduced, improving the mounting area efficiency and reducing the size of the application device. It becomes possible to plan.

  In addition, since the resin package 15 has the light emitting surface 151 having a convex lens shape protruding in the upper direction of the LED chip 10, it is possible to increase the light emission output.

<Second Embodiment>
FIG. 3 is a partial cross-sectional side view schematically showing an example according to the second embodiment of the resin-sealed light emitting device of the present invention.

  Compared with the first embodiment, the second embodiment has a structure in which the pair of electrodes of the LED chip 10a are separated from each other vertically, and the lower electrode of the LED chip 10a is the die of the first lead member 11. It is different in that it is fixed to the pad portion 110 and electrically connected thereto, and the others are the same. In the second embodiment, the first inner lead portion 111 of the first lead member 11 may be omitted. Further, in order to improve the adhesion strength between the first lead member 11 and the resin package 15, the second lead member 12 second in the width direction of the bottom surface of the die pad portion 110 of the first lead member 11. It is desirable to form at least one slit-like groove in the same manner as the first groove 123 on the bottom surface of the inner lead 121.

  Also by the resin-sealed light emitting device of the second embodiment, the same effects as those of the resin-sealed light emitting device of the first embodiment described above can be obtained.

  Hereinafter, each component in the light-emitting device of each above-mentioned embodiment is explained in full detail.

(First lead member 11 and second lead member 12) Each lead member preferably uses a high thermal conductor, and the surface thereof is subjected to metal plating such as silver, aluminum or gold on the surface of iron-containing copper or the like. It is preferable to improve the reflectance by smoothing. In this example, the surface of a copper (Cu) alloy plate is subjected to silver (Ag) plating. The thermal expansion coefficients of these metals are 16.7 × 10 ⁻⁶ / ° C. for copper (Cu) and 11.8 × 10 ⁻⁶ / ° C. for iron (Fe).

  (LED chip 10) The LED chip is a blue light emitting element having an emission peak wavelength in the vicinity of 460 nm, a blue-violet light emitting element having an emission peak wavelength in the vicinity of 410 nm, and an ultraviolet light emitting element having an emission peak wavelength in the vicinity of 365 nm. An element etc. can be used.

  The type of the light emitting element is not particularly limited, but for example, a nitride semiconductor such as InN, AlN, GaN, InGaN, AlGaN, InGaAlN, etc. formed as a light emitting layer on a substrate by MOCVD method, for example The n-type contact layer made of n-type GaN, the n-type cladding layer made of n-type AlGaN, and the p-type contact layer made of p-type GaN are sequentially stacked on the sapphire substrate. The semiconductor structure includes a homostructure having a MIS junction, a PIN junction, a PN junction, etc., a hetero bond, or a double hetero bond. Various emission wavelengths can be selected depending on the semiconductor material and the mixed crystal ratio. Moreover, it can be set as the single quantum well structure or the multiple quantum well structure which formed the semiconductor active layer in the thin film which produces a quantum effect. The active layer may be doped with donor impurities such as Si and Ge and / or acceptor impurities such as Zn and Mg. The emission wavelength of the light-emitting element can be changed from the ultraviolet region to red by changing the In content of InGaN in the active layer or changing the type of impurities doped in the active layer. (Bonding member to LED pad portion 110 of LED chip 10) For example, a light emitting element having blue light emission or green light emission and having a nitride semiconductor grown on a sapphire substrate is bonded onto a bed portion of a lead member (die bonding) ), An epoxy resin, silicone or the like can be used as the joining member. In consideration of deterioration due to light and heat from the light emitting element, it is also possible to use a brazing material such as Au—Sn eutectic solder or a low melting point metal without using a resin.

  On the other hand, when a light emitting element made of GaAs or the like and emitting red light emission is bonded onto the bed portion of the lead member, electrodes can be formed on both sides of the light emitting element, so that silver, gold, palladium can be used as the bonding member. A conductive paste such as can be used.

(Conductive wires 13, 14) The conductive wires are required to have good ohmic properties, mechanical connectivity, electrical conductivity and thermal conductivity with the electrodes of the light emitting element. The thermal conductivity, preferably ^{0.01cal / (S) (cm 2} ) (℃ / cm) or higher, more preferably is ^{0.5cal / (S) (cm 2} ) (℃ / cm) or more. In consideration of workability and the like, the diameter of the conductive wire is preferably 10 μm or more and 45 μm or less. Specific examples of such conductive wires include wires using metals such as gold, copper, platinum, and aluminum, and alloys thereof. Such a conductive wire can be easily bonded to each light emitting element and the internal terminal by a wire bonding apparatus.

  (Translucent resin for resin package 15) The translucent resin can be sealed so as to protect the light emitting element from external force, moisture, and the like. If water is contained in the translucent resin during the manufacturing process of the light emitting device or during storage at the manufacturing stage, it is contained in the resin by baking at 100 ° C for 14 hours or more. Since the generated moisture can be released to the outside air, adverse effects such as a steam explosion and a color shift caused by peeling between the light emitting element and the sealing member can be prevented.

  In addition, the sealing member is required to have high light transmittance in order to efficiently emit light from the light emitting element to the outside. In the structure in which the electrode of the light emitting element and the internal terminal portion are connected by a conductive wire, the sealing member also has a function of protecting the conductive wire. As a material of the translucent resin used as the sealing member, it is preferable to use a resin having excellent weather resistance such as an epoxy resin, a silicone resin, an acrylic resin, or a urea resin. Further, by adding a diffusing agent to the light-transmitting resin, directivity from the light-emitting element can be relaxed and the viewing angle can be increased.

The translucent resin preferably has a thermal thermal expansion coefficient close to that of the lead member. The translucent epoxy resin used in this example has a thermal thermal expansion coefficient of 6.3 × 10 ⁻⁵ / ° C., which is larger than the thermal thermal expansion coefficient of the lead member. The thermal expansion coefficient of the translucent epoxy resin is 16.5 × 10 ⁻⁵ / ° C. above the glass transition point (about 130 ° C.).

  For this reason, for example, even when the first conductive wire 13 and the second conductive wire 14 are each pulled by a transparent epoxy resin having a large thermal expansion when passing through a high-temperature reflow furnace during surface mounting, Since the first lead member 11 and the second lead member 12 are also pulled, the change in the relative relationship between the conductive wire and the lead member is reduced, and the first conductive wire 13 and the second conductive member are reduced. It is possible to prevent an electrical connection state of each second bond portion of the wire 14 from being lowered and an increase in poor electrical contact.

The LED chip 10 is a single-color light emitting element, and is excited by absorbing light emitted from the light emitting element into a light-transmitting resin for packaging and emitting light having a color different from that of the light emitting element. By including the fluorescent substance for wavelength conversion to be performed, it is possible to obtain desired mixed color emission according to the combination of the emission color of the light emitting element and the fluorescent substance in the translucent resin. In this case, a fluorescent substance for wavelength conversion that emits light having a complementary color relationship with the light emission color of the light emitting element (for example, a YAG phosphor (a lanthanoid such as Ce) in a translucent epoxy resin for a light emitting element emitting blue light). Incorporating rare earth aluminate phosphors, which are mainly activated with a system element), the content makes it possible to absorb yellow light that partially absorbs light from the blue light emitting element and to emit yellow light. A light-emitting device that emits white light can be formed relatively easily and reliably by mixing the light emitted from the light-emitting element and the light emitted from the YAG phosphor.Similarly, nitrogen-containing CaO—Al ₂ activated with Eu and / or Cr O ₃ when using -SiO ₂ phosphor is set in the content thereof, it is possible to emission of red light as a complementary color to absorb part of the light from the blue light emitting element, a blue light emitting element The light-emitting device of white relatively easy to reliably form the Align.

  Examples of the resin-sealed light emitting device of the present invention will be described below.

  As an example of the light emitting device of the present invention, a specific example of the first embodiment described above with reference to FIGS. 1 and 2A and 2B will be described.

  The first lead member 11 has a die pad portion 110 having a width of 1.2 mm and a thickness of 0.5 mm, a first inner lead portion 111 having a width of 1.0 mm and a thickness of 0.5 mm. The length is about 1.0 mm, the width of the first outer lead portion 112 is 2.0 mm, the thickness is 0.2 mm, and the length is about 2.0 mm.

  The cup-shaped recessed portion 110a on the upper surface of the die pad portion 110 of the first lead member 11 has a circular top surface at the outer peripheral portion and a bottom surface portion, a depth of 0.2 mm, and the diameter of the outer peripheral portion is The diameter of 1.0 mm and the bottom part is 0.6 mm.

  The second lead member 12 has a width of the second inner lead portion 121 of 1.2 mm, a thickness of 0.5 mm, and a length of about 1.0 mm, and the second outer lead portion 122 has a width of 2 mm. 0.0 mm, thickness is 0.2 mm, and length is about 2.0 mm. The length of the gap between the first lead member 11 and the second lead member 12 is 0.1 mm. Accordingly, as described later, the surface area of the contact portion between the resin package 15 and the second lead member 12 formed by transfer molding of a translucent resin is the contact portion between the resin package 15 and the first lead member 11. Is less than the surface area.

  One first groove 123 is formed in the vertical direction on both side surfaces of the second inner lead portion 122 of the second lead member 12, and the first groove 123 has a semicircular side surface. The radius (depth) is 0.1 mm and the width is 0.2 mm.

  Two slit-shaped second grooves 124 are formed in the width direction of the bottom surface of the second inner lead portion 122 of the second lead member 12, and the side surfaces of the second groove 124 are V-shaped. The groove has a depth of 0.05 mm, a V-shaped taper angle of 60 °, and a V-shaped opening angle of 60 °.

  Two slit-shaped third grooves 113 are formed in the width direction of the bottom surface of the first inner lead portion 111 of the first lead member 11, and the side surfaces of the third groove 113 are V-shaped. The groove has a depth of 0.05 mm, a V-shaped taper angle of 60 °, and a V-shaped opening angle of 60 °.

  The range of the depth and width of the first groove 123 is not limited as long as it is possible to make the second inner lead portion 122 have an area where wire bonding is possible. Further, the depths of the second groove 124 and the third groove 113 are not particularly limited.

  The horizontal distance from the center point of the recessed portion 110a of the die pad portion 110 of the first lead member 11 to the first groove 123 is 1 mm, and 2 from the center point of the recessed portion 110a of the die pad portion 110. The horizontal distances to the second grooves 124 are 0.9 mm and 1.1 mm, respectively, in the length direction from the center point of the recessed portion of the die pad part 110 to the two third grooves 113. The shortest lengths along are 0.9 mm and 1.1 mm, respectively.

  The conductive wires 13 and 14 are made of a gold wire having a diameter of 30 μm.

  Next, an example of a manufacturing process of the resin-sealed light emitting device having the above configuration will be briefly described.

  First, for example, a metal plate in which silver plating is made on the entire surface of a deoxidized copper alloy is punched with a mold, and a large number of lead frames each including a first lead portion and a first lead portion are arranged in a matrix. To form a lead frame array. For each lead frame of the lead frame array, two slit-shaped first grooves in the width direction of the bottom surface of the second inner lead part of the second lead member, and the second lead part second A second groove is formed in the vertical direction on both side surfaces of the inner lead portion, and two slit-shaped third grooves are formed in the width direction of the bottom surface of the first inner lead portion of the first lead portion. Keep it.

  Next, a light emitting element is die-bonded on the die pad portion of the first lead portion sequentially for each lead frame. Here, when using the light emitting element which has red light emission in which the electrode was formed in both surfaces as a light emitting element, die bonding is performed on a die bed part using a silver paste. On the other hand, when a blue or green light emitting element having a sapphire substrate as a bottom surface is used as the light emitting element, die bonding is performed on the die bed portion using an epoxy resin.

  Next, a conductive wire is bonded to the pair of electrodes of the light emitting element and the inner lead portions of the pair of lead portions in order with respect to each lead frame. Thereafter, the tensile strength of the conductive wire and the quality of the bonding connection are confirmed by sampling inspection as necessary.

  After that, using a transfer mold molding jig for the lead frame array, the light emitting element, the die pad portion of the first lead portion, the first inner lead portion, and the second lead portion for each lead frame The thermosetting translucent epoxy resin is transfer-molded so as to cover the second inner lead portion, the first conductive wire, and the second conductive wire. At this time, as a pattern of the lead frame array, full molding can be performed by previously opening at least both sides of the die pad portion and the inner lead portion of each lead frame. Then, the light-transmitting epoxy resin is thermally cured to form a resin package sealed with the resin in a tight contact state with the lead member.

  Thereafter, a large number of resin packages with outer leads, each having an outer lead portion protruding from the side surface of the resin package, are punched out and separated from the lead frame array.

  Then, for each resin package with an outer lead, the outer lead part is bent along the side surface of the resin package, and further bent to the bottom side of the resin package to form the external terminals 16 for surface mounting connection. A large number of surface-mounted resin-sealed light emitting devices are obtained.

  According to the resin-sealed light emitting device of the above embodiment, the second lead member is formed with one wide first groove in the vertical direction on both side surfaces of the second inner lead portion, Two slit-shaped second grooves each having a width smaller than that of the first groove are formed in the width direction of the bottom surface of the inner lead portion, and a part of the resin package is embedded in each of the grooves. Therefore, even if the surface area of the close contact portion with the resin package is small, the close contact strength with the resin package is improved. The first lead member also has two slit-like third grooves formed in the width direction of the bottom surface of the first inner lead part, and a part of the resin package is embedded in the groove. Therefore, the adhesion strength with the resin package is improved.

  Therefore, when the resin-sealed light-emitting device is surface-mounted on a substrate, each lead member is pulled in the same direction even if each conductive wire is pulled strongly by the package resin having a large thermal expansion. As a result, the thermal stress on each conductive wire and its second bond portion is relaxed, and it becomes possible to prevent electrical contact failure or disconnection of the second bond portion as much as possible, and the failure rate is reduced. As a result, it is possible to improve the reliability and yield of the thermal shock test, and to mount a large area, high output LED chip.

  The present invention also applies to a light receiving device in which a chip of a light receiving element such as a photodiode or a phototransistor is mounted on a lead frame, or a light receiving and emitting device in which a pair of a light emitting diode chip and a light receiving element chip is mounted on a lead frame. Applicable. Further, the electrical connection portion of the LED chip may be covered with a light-transmitting elastic material (for example, silicon resin), and the periphery thereof may be further covered with the light-transmitting resin.

The partial cross section side view which shows roughly an example which concerns on 1st Embodiment of the resin-sealed light-emitting device of this invention. The top view and side view which take out the lead member in FIG. 1, and expand and show the state before bending. The partial cross section side view which shows roughly an example which concerns on 2nd Embodiment of the resin-sealed light-emitting device of this invention. Sectional drawing which shows schematically the prior art example of a resin-sealed light-emitting device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... LED chip, 11 ... 1st lead member, 110 ... Die pad part, 110a ... Recessed part, 111 ... 1st inner lead part, 112 ... 1st outer lead part, 113 ... 3rd groove | channel , 12 ... second lead member, 121 ... second inner lead part, 122 ... second outer lead part, 123 ... first groove, 124 ... second groove, 13 ... first conductive wire, 14 ... second conductive wire, 15 ... resin package, 151 ... light emitting surface, 16 ... external terminal.

Claims (6)

A metal member is used, one end in the length direction becomes the die pad portion, the middle portion in the length direction becomes the first inner lead portion, and the other end in the length direction becomes the first outer lead portion. A first lead member,
A metal member is used, one end portion in the length direction becomes a second inner lead portion, the other end portion in the length direction becomes a second outer lead portion, and the first lead member and each one end A second lead member that is opposed with a predetermined gap therebetween,
A light emitting device having a pair of electrodes and mounted and fixed on the die pad portion of the first lead member;
A conductive wire having both ends bonded together so as to electrically connect one electrode of the pair of electrodes of the light emitting element and the second inner lead portion of the second lead member;
Transparent to cover the light emitting element, the die pad portion of the first lead member, the first inner lead portion of the first lead member, the second inner lead portion of the second lead member, and the conductive wire. A resin-sealed light emitting device having a resin package formed by transfer molding of a light-sensitive resin,
The second lead member is shorter and has a smaller surface area than the first lead member having the die pad portion, and the second inner lead portion has a flat plate shape with one end portion in the length direction being thick. Yes, the other end in the length direction of the thick part is a flat plate shape thinner than the thick part, and the conductive wire is bonded to the thick part of the second inner lead part. The first groove has at least 1 each facing the second bond portion in the vertical direction on both side surfaces of the second bond portion that is a connection portion between the second inner lead portion and the conductive wire. It is formed, and at least one second groove is formed in the width direction of the bottom surface of the second bond portion, and a part of the resin package is embedded in each of the grooves. Resin seal Type light-emitting device.   The first lead member is a die pad portion having a thick flat plate at one end in the length direction and having a cup-shaped recess on the upper surface, and an intermediate portion in the length direction is the die pad portion. It is a flat plate having a continuous thickness and becomes the first inner lead portion, and the other end portion in the length direction is a flat plate shape thinner than the first inner lead portion and becomes the first outer lead portion, 2. The resin-sealed light emitting device according to claim 1, wherein the light emitting element is mounted on the bottom surface of the concave portion of the die pad portion.   3. The resin-sealed light emitting device according to claim 1, wherein the second groove has a slit shape that is narrower than the first groove.   At least one slit-like third groove is formed in the width direction of the bottom surface of the first inner lead portion of the first lead member, and a part of the resin package is inside the third groove. The resin-sealed light-emitting device according to claim 1, wherein the resin-sealed light-emitting device is embedded.   The first lead member and the second lead member have outer lead portions protruding from the resin package along side surfaces of the resin package, and further, the distal end portion of the outer lead portion is bent toward the bottom surface side of the resin package. 5. The resin-sealed light emitting device according to claim 1, wherein an external terminal for surface mounting connection is configured.   6. The resin package according to claim 1, wherein the resin package is made of an epoxy resin, and the first lead member and the second lead member are members in which the entire surface of a copper alloy is silver-plated. The resin-sealed light emitting device according to item.

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